Posted By: varunner
Removing power valve - 04/25/19 01:20 AM
On a holley, when removing the power valve, do you jet up on just the primary or both circuits ? thanks !
Removing power valve
Posted By: AndyF
Re: Removing power valve - 04/25/19 01:24 AM
You add jet to the metering block which you removed the power valve from.
Posted By: varunner
Re: Removing power valve - 04/25/19 01:36 AM
thanks Andy, generally how many sizes ? I've heard anywhere from 2 - 10
Posted By: sgcuda
Re: Removing power valve - 04/25/19 02:05 AM
Usually 8-10 jet sizes. If you have the option, plug the PVCR's also.
Posted By: Cab_Burge
Re: Removing power valve - 04/25/19 02:22 AM
Which end of the carb are you removing the P.V. from? Why aren't you wanting use it?
Posted By: polyspheric
Re: Removing power valve - 04/25/19 03:24 AM
"Why aren't you wanting use it?"
THIS^^^
THIS^^^
Posted By: Clanton
Re: Removing power valve - 04/25/19 11:44 AM
8 sizes should do it.I have jetted 6 up on pri and 8/10 on sec and this will also help you know how your carb uses fuel.Be sure to not let the pv gasket leak.pump fuel will take less adjustment than race gas
Posted By: DaveRS23
Re: Removing power valve - 04/25/19 12:13 PM
The change in the main jet will depend on the size of the PVCRs under the power valve. You can take drill bits and measure the PVCR size and then with a little math figure how much bigger the mains need to be. It won't be exact, but will get a good close starting point for the rest of the tuning.
Power valves and PVCRs are good tuning tools. Rarely do they need to be eliminated, at least on the primaries.
Power valves and PVCRs are good tuning tools. Rarely do they need to be eliminated, at least on the primaries.
Posted By: varunner
Re: Removing power valve - 04/25/19 12:13 PM
so I'm having a heck of a time getting this engine to idle decent. Seems way too rich. Plugs are wet, inside of intake usually looks wet. It's 383 stock eliminator engine. It has 7-9 in. of vacuum at idle. The carb, R4668, w/vac secondaries, came from a carb guy with a 3.5 PV, I put a 2.5 in there, and it may have helped, not sure. So at this point I'd just like to get it out of there and see how it responds. The mixture screws seem to work right, and all butterflys have had a hole put in the them. Secondary block doesn't have a PV. Also the motor seems to run lean at WOT, this was seen on the dyno, 13.2, and inside of headers are white.
Posted By: polyspheric
Re: Removing power valve - 04/25/19 12:17 PM
It should NOT idle on the PV, something is wrong.
Reason#1 for "Take it out" advice: doesn't understand what it does.
Reason#1 for "Take it out" advice: doesn't understand what it does.
Posted By: Clanton
Re: Removing power valve - 04/25/19 01:00 PM
How many turns out are the idle metering screws?
Posted By: varunner
Re: Removing power valve - 04/25/19 01:29 PM
agreed it shouldn't. if removed, it won't. not sure how much you actually know about a holley on a stocker motor, but if you check around, most people remove them, just to simplify things. This engine will either be at idle or WOT, nothing in between.
Originally Posted by polyspheric
It should NOT idle on the PV, something is wrong.
Reason#1 for "Take it out" advice: doesn't understand what it does.
Reason#1 for "Take it out" advice: doesn't understand what it does.
Posted By: fast68plymouth
Re: Removing power valve - 04/25/19 01:48 PM
Often times, removing the PV will slightly improve the “hit” on the line.
I’d take it out and see what happens........ easy enough to put it back in.
Do the OE bowls have site plugs?
If not, I’m guessing the floats are a little too high, and/or the fuel pressure is slightly too high.
Holes in all 4 butterflies?
Better check the wording on that in the rules.
We had an issue with that years ago.
We had to replace the rear blades(with some that had no holes) before we could continue running, and they disallowed our qualifying runs.
An easy test is lift the carb off the manifold an inch or so, and block it up with something.
Turn on the fuel pump and see if any fuel starts dripping from anywhere underneath.
I’ve seen fuel dripping out from places where it theoretically “couldn’t”.
I’d take it out and see what happens........ easy enough to put it back in.
Do the OE bowls have site plugs?
If not, I’m guessing the floats are a little too high, and/or the fuel pressure is slightly too high.
Holes in all 4 butterflies?
Better check the wording on that in the rules.
We had an issue with that years ago.
We had to replace the rear blades(with some that had no holes) before we could continue running, and they disallowed our qualifying runs.
An easy test is lift the carb off the manifold an inch or so, and block it up with something.
Turn on the fuel pump and see if any fuel starts dripping from anywhere underneath.
I’ve seen fuel dripping out from places where it theoretically “couldn’t”.
Posted By: Get-X
Re: Removing power valve - 04/25/19 01:52 PM
Originally Posted by fast68plymouth
Often times, removing the PV will slightly improve the “hit” on the line.
I’d take it out and see what happens........ easy enough to put it back in.
Do the OE bowls have site plugs?
If not, I’m guessing the floats are a little too high, and/or the fuel pressure is slightly too high.
Holes in all 4 butterflies?
Better check the wording on that in the rules.
We had an issue with that years ago.
We had to replace the rear blades(with some that had no holes) before we could continue running, and they disallowed our qualifying runs.
I’d take it out and see what happens........ easy enough to put it back in.
Do the OE bowls have site plugs?
If not, I’m guessing the floats are a little too high, and/or the fuel pressure is slightly too high.
Holes in all 4 butterflies?
Better check the wording on that in the rules.
We had an issue with that years ago.
We had to replace the rear blades(with some that had no holes) before we could continue running, and they disallowed our qualifying runs.
Yup, I've seen guys get bounced for having the wrong head on the butterfly screws, let alone modding the butterfly's themselves.
Posted By: dvw
Re: Removing power valve - 04/25/19 02:01 PM
Your cam may enough duration that the signal is poor. Then it need more air to idle. Craig king the CV throttle blades exposes the transfer slot. Now the idle mixture is a mess. What you need is an air sorce to get the idle speed up without opening the blades or drilling the plates. Get creative, leaky PCV valve, base gasket, ect. Then it may take some adjustment to the idle air bleeds as well.
Doug
Doug
Posted By: varunner
Re: Removing power valve - 04/25/19 02:23 PM
1 1/2
Originally Posted by Clanton
How many turns out are the idle metering screws?
Posted By: varunner
Re: Removing power valve - 04/25/19 02:26 PM
I agree, easy to do.
no site plugs
in this day and age in stock, holes in butterflys I'm not worried about.
will definately lift the carb and if it drips. fuel pump pressure is 6 lbs.
no site plugs
in this day and age in stock, holes in butterflys I'm not worried about.
will definately lift the carb and if it drips. fuel pump pressure is 6 lbs.
Originally Posted by fast68plymouth
Often times, removing the PV will slightly improve the “hit” on the line.
I’d take it out and see what happens........ easy enough to put it back in.
Do the OE bowls have site plugs?
If not, I’m guessing the floats are a little too high, and/or the fuel pressure is slightly too high.
Holes in all 4 butterflies?
Better check the wording on that in the rules.
We had an issue with that years ago.
We had to replace the rear blades(with some that had no holes) before we could continue running, and they disallowed our qualifying runs.
An easy test is lift the carb off the manifold an inch or so, and block it up with something.
Turn on the fuel pump and see if any fuel starts dripping from anywhere underneath.
I’ve seen fuel dripping out from places where it theoretically “couldn’t”.
I’d take it out and see what happens........ easy enough to put it back in.
Do the OE bowls have site plugs?
If not, I’m guessing the floats are a little too high, and/or the fuel pressure is slightly too high.
Holes in all 4 butterflies?
Better check the wording on that in the rules.
We had an issue with that years ago.
We had to replace the rear blades(with some that had no holes) before we could continue running, and they disallowed our qualifying runs.
An easy test is lift the carb off the manifold an inch or so, and block it up with something.
Turn on the fuel pump and see if any fuel starts dripping from anywhere underneath.
I’ve seen fuel dripping out from places where it theoretically “couldn’t”.
Posted By: fast68plymouth
Re: Removing power valve - 04/25/19 02:26 PM
Unless the wording in the rule book has changed, drilling holes in the primary blades is legal....... and no mention of size limits, so they can be big enough to get plenty of air thru to attain a decent idle.
Generally the idle circuit in a factory carb will need some enrichment to supply enough fuel to achieve a decent idle with a cheater cam that has low vacuum.
Perhaps the mods that were done are a bit on the rich side already.
But I strongly suspect there is fuel flowing that’s independent of the motor running.
Generally the idle circuit in a factory carb will need some enrichment to supply enough fuel to achieve a decent idle with a cheater cam that has low vacuum.
Perhaps the mods that were done are a bit on the rich side already.
But I strongly suspect there is fuel flowing that’s independent of the motor running.
Posted By: varunner
Re: Removing power valve - 04/25/19 02:28 PM
I'll measure that and record.
I only have a very small amount of the transfer slot exposed.
thanks all.
I only have a very small amount of the transfer slot exposed.
thanks all.
Originally Posted by DaveRS23
The change in the main jet will depend on the size of the PVCRs under the power valve. You can take drill bits and measure the PVCR size and then with a little math figure how much bigger the mains need to be. It won't be exact, but will get a good close starting point for the rest of the tuning.
Power valves and PVCRs are good tuning tools. Rarely do they need to be eliminated, at least on the primaries.
Power valves and PVCRs are good tuning tools. Rarely do they need to be eliminated, at least on the primaries.
Posted By: fast68plymouth
Re: Removing power valve - 04/25/19 02:34 PM
I wouldn’t be trying to get it to idle at a low-ish rpm either........ 12-1300 in neutral, hot...... is where I’d be.
And, unless the car was moving........ it wouldn’t be in gear.
And, unless the car was moving........ it wouldn’t be in gear.
Posted By: madscientist
Re: Removing power valve - 04/25/19 02:42 PM
Originally Posted by fast68plymouth
I wouldn’t be trying to get it to idle at a low-ish rpm either........ 12-1300 in neutral, hot...... is where I’d be.
And, unless the car was moving........ it wouldn’t be in gear.
And, unless the car was moving........ it wouldn’t be in gear.
I agree with this 100%.
Posted By: MR_P_BODY
Re: Removing power valve - 04/25/19 02:49 PM
Not knowing what cam is in it I would
say that should idle at 900 rpm without any issue.. see if its dripping
fuel first thing
EDIT
is this car hard to start up.. you said the intake looks wet
say that should idle at 900 rpm without any issue.. see if its dripping
fuel first thing
EDIT
is this car hard to start up.. you said the intake looks wet
Posted By: 1DGEMAN
Re: Removing power valve - 04/25/19 03:25 PM
[quote=varunner]I agree, easy to do.
no site plugs
in this day and age in stock, holes in butterflys I'm not worried about.
will definately lift the carb and if it drips. fuel pump pressure is 6 lbs.
What size needle and seats? 6lbs could be too much fuel pressure. On my 6 pack 340 for stock eliminator I am experimenting with .130 needle and seats with 3/8 line and 4 psi it cleaned up the idle on the run stand. What rpm do you have it idling at? There is a lot of duration in our camshafts not meant to idle.
Good Luck, Rod
no site plugs
in this day and age in stock, holes in butterflys I'm not worried about.
will definately lift the carb and if it drips. fuel pump pressure is 6 lbs.
What size needle and seats? 6lbs could be too much fuel pressure. On my 6 pack 340 for stock eliminator I am experimenting with .130 needle and seats with 3/8 line and 4 psi it cleaned up the idle on the run stand. What rpm do you have it idling at? There is a lot of duration in our camshafts not meant to idle.
Good Luck, Rod
Posted By: ZIPPY
Re: Removing power valve - 04/25/19 03:41 PM
Originally Posted by fast68plymouth
An easy test is lift the carb off the manifold an inch or so, and block it up with something.
Turn on the fuel pump and see if any fuel starts dripping from anywhere underneath.
I’ve seen fuel dripping out from places where it theoretically “couldn’t”.
This procedure really works great, done it many times myself...found things I both did, and did not want to find.
...rotten luck with warped parts.
Posted By: AndyF
Re: Removing power valve - 04/25/19 03:51 PM
Had you started out your thread by saying it was a stock eliminator engine it would've made more sense. Stock eliminator carbs tend to be a special breed. I've seen a few of them but I wouldn't know how to build one.
You might not have a problem, or at least not one that can be easily fixed. If the engine has a lot of reversion at idle then you'll have sooty plugs and a wet intake but the engine will run fine down the track. That is just the way it is. I've seen guys fix that by playing around with the valve job but that is another thing that I've only seen but not understood. Sometimes a very minor change to the valve job will clean up the idle without changing the power at WOT. A stock eliminator head guy might know how to do that.
You might not have a problem, or at least not one that can be easily fixed. If the engine has a lot of reversion at idle then you'll have sooty plugs and a wet intake but the engine will run fine down the track. That is just the way it is. I've seen guys fix that by playing around with the valve job but that is another thing that I've only seen but not understood. Sometimes a very minor change to the valve job will clean up the idle without changing the power at WOT. A stock eliminator head guy might know how to do that.
Posted By: fast68plymouth
Re: Removing power valve - 04/25/19 04:53 PM
I’ll add that my buddies Pontiac Stocker idles just fine with the Qjet....... but it was a learning process on what it took to make it that way.
Lots of modifications to the low speed circuits.
He has a variety of carbs....... and on one of them we had to remove the primary metering rods to get any kind of throttle response from it(this seems to be pretty common with Stocker Qjets).
He now knows what series of things need to get plugged, what things need to get drilled, etc.......to get it to run right.
It took some time to get it figured out.
I’d think/expect it to be easier with a Holley.
Thinking about it more......
Even Holleys with “2 corner idle” have a secondary idle circuit, it’s just fixed instead of adjustable.
If the secondary idle circuit had been richened up too much...... that could be part of the problem.
You’re sure the ignition isn’t compromised, and you’re running hot enough plugs?
Lots of modifications to the low speed circuits.
He has a variety of carbs....... and on one of them we had to remove the primary metering rods to get any kind of throttle response from it(this seems to be pretty common with Stocker Qjets).
He now knows what series of things need to get plugged, what things need to get drilled, etc.......to get it to run right.
It took some time to get it figured out.
I’d think/expect it to be easier with a Holley.
Thinking about it more......
Even Holleys with “2 corner idle” have a secondary idle circuit, it’s just fixed instead of adjustable.
If the secondary idle circuit had been richened up too much...... that could be part of the problem.
You’re sure the ignition isn’t compromised, and you’re running hot enough plugs?
Posted By: varunner
Re: Removing power valve - 04/25/19 10:22 PM
Ok, to answer some questions. I have had the idle set at 1200 which seems about right, it eventually after a few runs drop down to 500-600. I feel this is because of the spark plugs are getting fouled up.
needle/seat is 120
I set the carb above the intake and ran the pump. nothing came out of the base of the carb. But the fuel pressure crept up from 6 to 8 lbs in a few minutes. Fuel cell is full, the pump has a return back to the cell. Came back a couple hrs later and re-did the test, pressure crept from 6-7. Once I start it I'll watch it and see what it does with the engine running.
changed the oil and plugs.
After to talking to the guy who built the carb, he feels removing the power valve will lead to more problems, so I leave leave the 2.5 PV in for the weekend TnT at vmp
Dwayne, after I last talked to you. I re-did the intake gaskets as I thought a leak there might be contributing to the spark plug issue. I went to budds creek and improved from a 12.61 to a 11.79/111 1.56 60ft. convertor flashed to 5K The only changes w ere intake gaskets and spark plugs. I can deal with a less than stellar idle, but fuel in the oil and the plugs drenched in gas needs to get addressed.
needle/seat is 120
I set the carb above the intake and ran the pump. nothing came out of the base of the carb. But the fuel pressure crept up from 6 to 8 lbs in a few minutes. Fuel cell is full, the pump has a return back to the cell. Came back a couple hrs later and re-did the test, pressure crept from 6-7. Once I start it I'll watch it and see what it does with the engine running.
changed the oil and plugs.
After to talking to the guy who built the carb, he feels removing the power valve will lead to more problems, so I leave leave the 2.5 PV in for the weekend TnT at vmp
Dwayne, after I last talked to you. I re-did the intake gaskets as I thought a leak there might be contributing to the spark plug issue. I went to budds creek and improved from a 12.61 to a 11.79/111 1.56 60ft. convertor flashed to 5K The only changes w ere intake gaskets and spark plugs. I can deal with a less than stellar idle, but fuel in the oil and the plugs drenched in gas needs to get addressed.
Posted By: varunner
Re: Removing power valve - 04/25/19 10:25 PM
yeah it could be just a lot of mods that will be needed. ignition seems fine, locked out at 38. plugs are what you had recommended. I hadn't thought about hotter plugs.....
Originally Posted by fast68plymouth
I’ll add that my buddies Pontiac Stocker idles just fine with the Qjet....... but it was a learning process on what it took t make it that way.
Lots of modifications to the low speed circuits.
He has a variety of carbs....... and on one of them we had to remove the primary metering rods to get any kind of throttle response from it(this seems to be pretty common with Stocker Qjets).
He now knows what series of things need to get plugged, what things need to get drilled, etc.......to get it to run right.
It took some time to get it figured out.
I’d think/expect it to be easier with a Holley.
Thinking about it more......
Even Holleys with “2 corner idle” have a secondary idle circuit, it’s just fixed instead of adjustable.
If the secondary idle circuit had been richened up too much...... that could be part of the problem.
You’re sure the ignition isn’t compromised, and you’re running hot enough plugs?
Lots of modifications to the low speed circuits.
He has a variety of carbs....... and on one of them we had to remove the primary metering rods to get any kind of throttle response from it(this seems to be pretty common with Stocker Qjets).
He now knows what series of things need to get plugged, what things need to get drilled, etc.......to get it to run right.
It took some time to get it figured out.
I’d think/expect it to be easier with a Holley.
Thinking about it more......
Even Holleys with “2 corner idle” have a secondary idle circuit, it’s just fixed instead of adjustable.
If the secondary idle circuit had been richened up too much...... that could be part of the problem.
You’re sure the ignition isn’t compromised, and you’re running hot enough plugs?
Posted By: varunner
Re: Removing power valve - 04/25/19 10:35 PM
plug and carb
Posted By: madscientist
Re: Removing power valve - 04/25/19 11:32 PM
Originally Posted by varunner
plug and carb
For whatever reason that thing is pig rich. Everywhere. I suspect when you get the idle circuit cleaned up and work on main jet, you'll find you'll need a power valve that opens way sooner than 2.5 or even 4.5. That's too late for most engines.
Posted By: fast68plymouth
Re: Removing power valve - 04/26/19 12:18 AM
Those are 4150 carbs(rear metering block instead of metering plate) from the factory?
I didn’t realize that.
The ifr situation on the primary block doesnt appear to be the same as the typical “performance” Holley carb.
Does it utilize an emulsion tube in the main well?
I’m not sure if an aftermarket billet metering block would fly or not....... but I think I’d try and find out.
That plug looks as though there’s fuel “running” out of the carb....... did you try seeing if anything was dripping with the pump running?
You didn’t fog the motor after the last outing did you?
The plugs are 6’s?
I didn’t realize that.
The ifr situation on the primary block doesnt appear to be the same as the typical “performance” Holley carb.
Does it utilize an emulsion tube in the main well?
I’m not sure if an aftermarket billet metering block would fly or not....... but I think I’d try and find out.
That plug looks as though there’s fuel “running” out of the carb....... did you try seeing if anything was dripping with the pump running?
You didn’t fog the motor after the last outing did you?
The plugs are 6’s?
Posted By: BradH
Re: Removing power valve - 04/26/19 12:29 AM
If it's anything like the OEM 383 Holley I had years ago, it would not have come with a secondary metering block and the primary block would have had a tube in the main well. What's legal to replace for carb tuning purposes in Stock? A standard 650 DP primary block and an aftermarket 4160-type plate (not a conversion block) that allows for adjustable circuits might be easier to work with.
Posted By: fast68plymouth
Re: Removing power valve - 04/26/19 01:59 AM
I just saw you had answered a few questions......
So, if fuel isn’t leaking through the carb statically, it would point a finger at what appears to be a gross calibration issue.
With the motor warmed up and idling at 1200....... can you kill it by turning the mixture screws in?
When the idle starts to slow down from presumably being rich..... does turning those screws in help?
When you say the distributor is locked....... that means “locked”....... not there is super weak springs in it, right?
With .120 n/s, you can probably drop the pressure to 5-ish.
When it’s warmed up and idling at 1200, if you look down the Venturi there should be no fuel dribbling from the boosters.
Glad to hear you’re making headway with it.
So, if fuel isn’t leaking through the carb statically, it would point a finger at what appears to be a gross calibration issue.
With the motor warmed up and idling at 1200....... can you kill it by turning the mixture screws in?
When the idle starts to slow down from presumably being rich..... does turning those screws in help?
When you say the distributor is locked....... that means “locked”....... not there is super weak springs in it, right?
With .120 n/s, you can probably drop the pressure to 5-ish.
When it’s warmed up and idling at 1200, if you look down the Venturi there should be no fuel dribbling from the boosters.
Glad to hear you’re making headway with it.
Posted By: fast68plymouth
Re: Removing power valve - 04/26/19 02:19 AM
This is supposedly a pic of a 71 383HP carb.
A little out of the ordinary(if the pic is of the correct carb).
4160 series(no rear metering block), with down leg boosters.
Brian....... does yours have the same style boosters?
Front and rear?
A little out of the ordinary(if the pic is of the correct carb).
4160 series(no rear metering block), with down leg boosters.
Brian....... does yours have the same style boosters?
Front and rear?
Posted By: fast68plymouth
Re: Removing power valve - 04/26/19 02:27 AM
Okay...... we may be getting somewhere.......
If what’s said in this thread is true....... then some serious reworking of the low speed circuits would have had to be done for this application......
https://www.forbbodiesonly.com/moparforum/threads/pic-request-1971-383hp-with-factory-holley.97491/
If what’s said in this thread is true....... then some serious reworking of the low speed circuits would have had to be done for this application......
https:/
Posted By: Cab_Burge
Re: Removing power valve - 04/26/19 03:42 AM
When I see shiny plugs I try to fix the oiling issue first 
Once that is cured you can work on the proper AFR and circuits
Once that is cured you can work on the proper AFR and circuits
Posted By: varunner
Re: Removing power valve - 04/26/19 11:29 AM
easy to start
Originally Posted by MR_P_BODY
Not knowing what cam is in it I would
say that should idle at 900 rpm without any issue.. see if its dripping
fuel first thing
EDIT
is this car hard to start up.. you said the intake looks wet
say that should idle at 900 rpm without any issue.. see if its dripping
fuel first thing
EDIT
is this car hard to start up.. you said the intake looks wet
Posted By: varunner
Re: Removing power valve - 04/26/19 11:35 AM
On the secondary metering block, my carb guy asked if I wanted one, he said some guys do it some don't , so I said sure do it. Supposedly only advantage is changing jets. If it doesn't fly I'll remove and put a plate on it. I have another carb getting done without it. So with a plate how do you richen or lean it out ? different plates or can you modify it ?
Posted By: varunner
Re: Removing power valve - 04/26/19 11:37 AM
the oil had been there, that is why is changed gaskets on the intake. I'd say it is sealed well. Leak down and compression is good.
Originally Posted by Cab_Burge
When I see shiny plugs I try to fix the oiling issue first
Once that is cured you can work on the proper AFR and circuits
Once that is cured you can work on the proper AFR and circuits
Posted By: varunner
Re: Removing power valve - 04/26/19 11:47 AM
Dwayne,
plugs are 6
distributor has no spring, plates located.
plugs are 6
distributor has no spring, plates located.
Posted By: varunner
Re: Removing power valve - 04/26/19 11:57 AM
thanks for the link. I've read some about this carb, as far as the mixture screws, I must not have the original metering block because turning the screws in will kill the motor. once I start it today I'll try to lean it out a bit with the mixture screws. I've tried adjusting the screws with a vac gage and the tach, always end up at 1 1/2 - 1 3/4 out for highest idle. Need to find some zinc additive before I start it, ran out of the comp cams additive I've been using.
Originally Posted by fast68plymouth
Okay...... we may be getting somewhere.......
If what’s said in this thread is true....... then some serious reworking of the low speed circuits would have had to be done for this application......
https://www.forbbodiesonly.com/moparforum/threads/pic-request-1971-383hp-with-factory-holley.97491/
If what’s said in this thread is true....... then some serious reworking of the low speed circuits would have had to be done for this application......
https:/
Posted By: fast68plymouth
Re: Removing power valve - 04/26/19 01:54 PM
I’d check the sizes of the pri and sec ifr’s and iab’s....... to see if their sizes seem to make sense.
Posted By: BradH
Re: Removing power valve - 04/26/19 06:36 PM
Originally Posted by varunner
On the secondary metering block, my carb guy asked if I wanted one, he said some guys do it some don't , so I said sure do it. Supposedly only advantage is changing jets. If it doesn't fly I'll remove and put a plate on it. I have another carb getting done without it. So with a plate how do you richen or lean it out ? different plates or can you modify it ?
Aftermarket plates can use standard Holley jets, but you'll need to be sure the jets don't interfere with the float's range of motion.
Check Quick Fuel and AED and see what they offer.
Posted By: varunner
Re: Removing power valve - 04/26/19 11:28 PM
Thanks for the help so far. So I started it up and set the fuel pressure at 6 psi, seemed stable for the 10 minutes I ran it. You couldn't smell any gas with it idling. I set the mixture at 1 1/4 out. It sounded ok, I shot a video of it idling, but the sound quality is pretty bad. I'll run it tomorrow at a TnT and see how it runs. Afterwards I'll check the plugs and oil. Attached are the specs I got from the carb guy, feel free to comment on it.
Posted By: varunner
Re: Removing power valve - 04/27/19 12:05 AM
Posted By: varunner
Re: Removing power valve - 05/30/19 03:17 PM
I thought I'd update this thread. I've only made a few more passes with this car. At VMP I lower the 60ft. from 1.58 to 1.50. I got rid of the secondary metering block and have been working on closing the throttle plates to close up the transfer slots. I opened up the holes in the throttle plates to .150" and was able to close up the transfer slot to @.050" I further opened the holes to .180" which is I think alot. This did not allow me to close the transfer slots up any more, so I think I'm done there. Would opening the idle air bleed help with this effort ? The main issue is still there and that is liquid fuel in the plentum floor of the intake and fuel fowled plugs.
This is interesting, I had a sample of the oil tested. They could not find any fuel in the oil, but they did find lead and water. I think and hope the lead and water are from the fuel, sunoco 110. The last thing I want to mention is that, is it possible that the fuel in the intake and plugs are because of blocking the heat crossover in the intake ? The heat is to atomize the gas as I understand. So maybe a hotter plug is all I need to do........
This is interesting, I had a sample of the oil tested. They could not find any fuel in the oil, but they did find lead and water. I think and hope the lead and water are from the fuel, sunoco 110. The last thing I want to mention is that, is it possible that the fuel in the intake and plugs are because of blocking the heat crossover in the intake ? The heat is to atomize the gas as I understand. So maybe a hotter plug is all I need to do........
Posted By: fast68plymouth
Re: Removing power valve - 05/31/19 09:02 PM
Imo, this a classic case of where substituting a “known good” part would help shed some light of where to look.
My suggestion is to see if maybe one of your racing buddies has a known good working bracket race carb with 4 corner idle you could put on the motor........ run it for a while, get the motor up to operating temp, etc...... then pull it off and see if the manifold is wet like with the other carb or not.
If the plugs aren’t wet, and the manifold looks normal....... you know it’s simply a carb issue, and can stop looking at other items as being where the problem is.
From this side of the keyboard...... I’m betting it’s a carb issue.
My 383, which had a bigger cam than yours, and blocked heat crossover didn’t have a wet manifold plenum, and the same set of plugs were used for well over 100 dyno pulls and probably 200 passes in the car(3 seasons)....... and still looked fine.
Also...... with regards to the blocked heat crossover....... my guess is virtually every good running stocker has a blocked heat crossover(not to mention the countless other race car motors that use “air gap” style manifolds without crossover heat).
Of course, I had a good working carb with low speed calibration suited towards poor carb signal at lower rpms.
I won’t get into a debate over it, but the 2.5pv isn’t what you want.
My suggestion is to see if maybe one of your racing buddies has a known good working bracket race carb with 4 corner idle you could put on the motor........ run it for a while, get the motor up to operating temp, etc...... then pull it off and see if the manifold is wet like with the other carb or not.
If the plugs aren’t wet, and the manifold looks normal....... you know it’s simply a carb issue, and can stop looking at other items as being where the problem is.
From this side of the keyboard...... I’m betting it’s a carb issue.
My 383, which had a bigger cam than yours, and blocked heat crossover didn’t have a wet manifold plenum, and the same set of plugs were used for well over 100 dyno pulls and probably 200 passes in the car(3 seasons)....... and still looked fine.
Also...... with regards to the blocked heat crossover....... my guess is virtually every good running stocker has a blocked heat crossover(not to mention the countless other race car motors that use “air gap” style manifolds without crossover heat).
Of course, I had a good working carb with low speed calibration suited towards poor carb signal at lower rpms.
I won’t get into a debate over it, but the 2.5pv isn’t what you want.
Posted By: varunner
Re: Removing power valve - 05/31/19 09:54 PM
I agree with ya Dwayne. The atomization thought is just drawing for straws. Anyway, I made some progress. Someone suggested I check the body and baseplate of the carb for flatness. I did and the body was warped .011" So re-assembled it and I cranked down on the screws best I could without striping the threads, put it back together and ran it. The last few times I've run this engine,the vacuum floats from 8-12 in. with the rpm tracking the the vacuum. Took off the carb and there was still fuel in the intake, maybe a little less. I took the carb base plate off and the base, body, and gasket were pretty much dry. Previously they were soaking wet. Far from a slam dunk, but it's worth pursuing. I think I will try to re-surface the body and get a new gasket.
Any suggestion on a PV ?
Any suggestion on a PV ?
Posted By: fast68plymouth
Re: Removing power valve - 05/31/19 11:21 PM
The only thing a PV will do for that application is help keep the plugs cleaner when you’re putting around the pits.
I like the rating to be pretty high so it opens early on in the throttle opening at the starting line.
I’d also prefer it not to be real close to the vacuum reading at idle, if possible, so it doesn’t fluctuate open/closed during idle.
I’d be using something around 6.5-8.5........ and if it’s just open all the time at idle, that’s fine(usually helps with throttle response in that type of application).
Without seeing the carb myself and what’s been done to the low speed circuits, my suspicion is that the conversion from a “reverse” idle circuit to a “normal” idle circuit isn’t quite right for the application.
I’d want the primary idle/transition circuit(including ifr/air bleed sizing and placement) to be laid out just like a normal non-emmisions calbrated carb is.
In having messed with this stuff for almost 40 years........ my experience is that nothing is better for isolating a potential carb problem...... to the carb............than swapping it for a known good carb.
Basically, my viewpoint is........ if you put something like a QFT Q-750 on it......., assuming that carb was working as it was intended to........ the wet plenum and fouled plugs would go away.
And if that happened, you’d know the problem was strictly a carb issue.
I like the rating to be pretty high so it opens early on in the throttle opening at the starting line.
I’d also prefer it not to be real close to the vacuum reading at idle, if possible, so it doesn’t fluctuate open/closed during idle.
I’d be using something around 6.5-8.5........ and if it’s just open all the time at idle, that’s fine(usually helps with throttle response in that type of application).
Without seeing the carb myself and what’s been done to the low speed circuits, my suspicion is that the conversion from a “reverse” idle circuit to a “normal” idle circuit isn’t quite right for the application.
I’d want the primary idle/transition circuit(including ifr/air bleed sizing and placement) to be laid out just like a normal non-emmisions calbrated carb is.
In having messed with this stuff for almost 40 years........ my experience is that nothing is better for isolating a potential carb problem...... to the carb............than swapping it for a known good carb.
Basically, my viewpoint is........ if you put something like a QFT Q-750 on it......., assuming that carb was working as it was intended to........ the wet plenum and fouled plugs would go away.
And if that happened, you’d know the problem was strictly a carb issue.
Posted By: fast68plymouth
Re: Removing power valve - 05/31/19 11:35 PM
Here’s a post I made recently on another board about the value of the known good carb:
Quote
As a slightly off topic example of the value of “known good”.....
I tested a motor for a customer who had several new carbs to try, and one other which was supposed to be known good.
It was a new motor combo, so no previous history to judge by.
Started with the known good carb........ carb seems to need an abnormal amount of jet to get a/f ratios where they should be, and then starts to become somewhat numb to increases in jet.
We’ve got lots of carbs to try......so, install another one....... and then one or two more.
All were different Venturi diameter sizes, along with different booster configurations.
They all exhibited the same two qualities....... really really rich at part throttle...... all took way more jet than they should have to get the a/f ratios where they should be...... and were still kinda lean.......with a gradual leaning out throughout the pull.
Well, as it turned out, the known good carb had the main body substituted....... so it wasn’t exactly the known good carb anymore.
At the end of the day, we installed one of my “known good” dyno carbs.
No problems with the overly rich part throttle operation, and it didn’t require any jet changes at all to have normal wot a/f ratios.
In fact it was the richest of all the carbs tried, with way way smaller jets in it.
This carb has a tendency to slightly richen as the rpm increases, which it did on this motor as well....... the exact opposite of the tendency of the other carbs.
Prior to installing that last carb, there was speculation that perhaps the new combo was presenting some sort of unique fuel delivery issue that the carbs were having a hard time coping with.
In the end, that wasn’t the issue at all........ it was just the other carbs tunes were all that far off.
Which was made instantly clear once the motor was run with the “known good” carb.
I tested a motor for a customer who had several new carbs to try, and one other which was supposed to be known good.
It was a new motor combo, so no previous history to judge by.
Started with the known good carb........ carb seems to need an abnormal amount of jet to get a/f ratios where they should be, and then starts to become somewhat numb to increases in jet.
We’ve got lots of carbs to try......so, install another one....... and then one or two more.
All were different Venturi diameter sizes, along with different booster configurations.
They all exhibited the same two qualities....... really really rich at part throttle...... all took way more jet than they should have to get the a/f ratios where they should be...... and were still kinda lean.......with a gradual leaning out throughout the pull.
Well, as it turned out, the known good carb had the main body substituted....... so it wasn’t exactly the known good carb anymore.
At the end of the day, we installed one of my “known good” dyno carbs.
No problems with the overly rich part throttle operation, and it didn’t require any jet changes at all to have normal wot a/f ratios.
In fact it was the richest of all the carbs tried, with way way smaller jets in it.
This carb has a tendency to slightly richen as the rpm increases, which it did on this motor as well....... the exact opposite of the tendency of the other carbs.
Prior to installing that last carb, there was speculation that perhaps the new combo was presenting some sort of unique fuel delivery issue that the carbs were having a hard time coping with.
In the end, that wasn’t the issue at all........ it was just the other carbs tunes were all that far off.
Which was made instantly clear once the motor was run with the “known good” carb.
Posted By: varunner
Re: Removing power valve - 06/01/19 12:31 AM
Agreed, it's the first thing I'd try if I had one. When I first got this carb back, I couldn't get it to idle under 2K, in order to diagnosis that I borrowed a carb that was just "re-built", it was in bad shape, coughing and back-firing. So I had an old 600 that I put on, it had multiple leaks. Nothing else local to pick from. So if I had a carb that I knew was good I'd put it on, but doing so wouldn't tell me much about the one I'm trying to fix. I'm all for swapping parts, but I'm sure my current carb is the issue. I have another carb getting done and will have it a few weeks. Looking forward to that. But I do think I'm on the right track, at least I hope so. I re-finished the carb body tonight and will try it tomorrow, although I don't have a new gasket yet.
Thanks for the tip on the PV
Thanks for the tip on the PV
Posted By: varunner
Re: Removing power valve - 06/07/19 12:50 PM
Ok, I have finally found the real issue here. I did end up re-surfacing the bottom of the body and that is sealed up well. My original thought was to take out the power valve, I never tried that. So after looking at the baseplate, a lightbulb flickered on. First picture shows how I originally had it put together, second one is the fix.
.jpg "20190606_151045_1559910040586_resized (2).jpg")
.jpg "20190606_151106_1559910039122_resized (2).jpg")
Posted By: fast68plymouth
Re: Removing power valve - 06/07/19 01:35 PM
I’m not sure what I’m supposed to be looking at that would make the light bulb turn on......... but I doubt from the factory they came with an open gasket installed between the carb and manifold.
Not that it shouldn’t work fine....... just that they also worked fine without it.
Not that it shouldn’t work fine....... just that they also worked fine without it.
Posted By: varunner
Re: Removing power valve - 06/07/19 01:47 PM
The first gasket blocked off the passage that delivers manifold vacuum to the back side of the power valve. Manifold vacuum is what keeps it closed. The original gasket and insulator were open, not 4 hole.
Posted By: madscientist
Re: Removing power valve - 06/07/19 01:50 PM
Originally Posted by varunner
The first gasket blocked off the passage that delivers manifold vacuum to the back side of the power valve. Manifold vacuum is what keeps it closed. The original gasket and insulator were open, not 4 hole.
I don't think the gasket blocked anything off. Those channels expose the power valve port to manifold vacuum regardless of the gasket sitting on top of it.
Posted By: fast68plymouth
Re: Removing power valve - 06/07/19 01:51 PM
The first gasket does not block that cavity.
That’s what the “x” channel cut into the baseplate is for.
Furthermore....... the PV is not part of the idle circuit....... so open or closed....... does not affect the idle A/F ratio.
So, if the motor is loading up the plugs while idling...... the PV is not the source of the extra fuel...... unless it’s leaking fuel past the gasket or is torn.
But....... you’ll know shortly after you’ve got it running again if you’ve solved the problem or not.
That’s what the “x” channel cut into the baseplate is for.
Furthermore....... the PV is not part of the idle circuit....... so open or closed....... does not affect the idle A/F ratio.
So, if the motor is loading up the plugs while idling...... the PV is not the source of the extra fuel...... unless it’s leaking fuel past the gasket or is torn.
But....... you’ll know shortly after you’ve got it running again if you’ve solved the problem or not.
Posted By: varunner
Re: Removing power valve - 06/07/19 02:06 PM
Well, the only way I can see on this carb for the PV to get vacuum is from the opening in the base plate that was covered. And if the power valve is open, that fuel would be coming out of the booster, correct ? What I know for sure is that the idle changed a bunch with the other gasket, and the manifold vacuum also stabilized. Before it would stay above 10 in. then drop to about 5 in. and the motor would almost die, then it would cycle back and forth. now it's rock solid at 9 in. plugs are dry now too. I'm not a carb expert, but changing the gasket made a big difference, that's for sure.
Posted By: varunner
Re: Removing power valve - 06/07/19 02:08 PM
oh, and to add, I called holley and asked if it was a reverse idle carb and they no. hard to find any info on this carb for some reason. R-4668
Posted By: fast68plymouth
Re: Removing power valve - 06/07/19 02:19 PM
I’ve seen things solve problems before, when they shouldn’t have.
But as has been said, the x channel that’s connected to that PV signal cavity in the carb is only there to provide access to vacuum for that cavity when a 4 hole gasket is employed.
Did you try the carb with the 4 hole gasket after you milled the baseplate?
The open gasket looks a lot thicker and more compliant than the 4 hole you’re using.
My guess is if you installed a std 4 hole gasket made out of the same material, and the same thickness as the open gasket you have...... it would run the same.
I’ll add this...... all Holley 4bbl carbs use that cavity for the PV vacuum...... and they all seem to retain PV functionality just fine when used with a 4 hole gasket.
The only reason I thought it had the backwards idle circuit was because of the info provided in the link I posted, which seemed like it was coming from someone well versed in that particular carb.
I’ve never had one of that list number carbs in my hands.
9” of idle vacuum is surprisingly good for that combo.
The fuel that gets added to the main circuit by the PV would only be coming out of the booster(along with the fuel from the main jet) if enough air is flowing through the Venturi to activate the main circuit.
But as has been said, the x channel that’s connected to that PV signal cavity in the carb is only there to provide access to vacuum for that cavity when a 4 hole gasket is employed.
Did you try the carb with the 4 hole gasket after you milled the baseplate?
The open gasket looks a lot thicker and more compliant than the 4 hole you’re using.
My guess is if you installed a std 4 hole gasket made out of the same material, and the same thickness as the open gasket you have...... it would run the same.
I’ll add this...... all Holley 4bbl carbs use that cavity for the PV vacuum...... and they all seem to retain PV functionality just fine when used with a 4 hole gasket.
The only reason I thought it had the backwards idle circuit was because of the info provided in the link I posted, which seemed like it was coming from someone well versed in that particular carb.
I’ve never had one of that list number carbs in my hands.
9” of idle vacuum is surprisingly good for that combo.
Quote
And if the power valve is open, that fuel would be coming out of the booster, correct ?
The fuel that gets added to the main circuit by the PV would only be coming out of the booster(along with the fuel from the main jet) if enough air is flowing through the Venturi to activate the main circuit.
Posted By: Clanton
Re: Removing power valve - 06/07/19 02:57 PM
I don't like to use the 4 hole gasket unless you use a 4 hole space or the intake supporting it.the gasket could get sucked in the engine.
Posted By: varunner
Re: Removing power valve - 06/07/19 03:35 PM
This must really be an odd ball carb. On mine the only thing the x channel in the main body feeds is the hot-idle compensator on the side on the body, which is plugged. The only passage from the vacuum space behind the PV, goes down thru the body and lines up with the passage in the base plate that was covered. Arrow in the picture points to it.
The second pic shows the vacuum space as being wet. That doesn't seem right. The PV is new, gasket is new and I've been careful how the gasket lines up
yes I did try the 4 hole gasket with the re-surfaced base plate, gasket looked drier after disassembly, but not much of a difference in the idle
.jpg "20190607_104903_1559919128120_resized (2).jpg")
The second pic shows the vacuum space as being wet. That doesn't seem right. The PV is new, gasket is new and I've been careful how the gasket lines up
yes I did try the 4 hole gasket with the re-surfaced base plate, gasket looked drier after disassembly, but not much of a difference in the idle
Posted By: varunner
Re: Removing power valve - 06/07/19 03:36 PM
spacer was a 4 hole. I'm now going with a new open spacer and matching gaskets.
Posted By: fast68plymouth
Re: Removing power valve - 06/07/19 08:31 PM
Sorry, total brain fart on my part.
The PV gets its signal from that hole at the bottom of the cavity, into a hole in the baseplate,(just like yours), but the hole in the typical “universal carb” baseplate has a little “v” channel to get vacuum when the 4 hole gasket is used(see pic).
I don’t know what I was thinking about with the cavity in the center of the carb and the PV
(Looking at your pic with the 4 hole gasket in place...... it still doesn’t appear as though the gasket “sealed off” that front cavity.
It would only need a leak with as much area as the size of the hole from the base into the PV cavity).
You sure those extra screw threads from the bottom aren’t interfering with how the PV slides into the cavity?
You could still try plugging the PV.
Measure the PVCR, calculate the area.
Calculate the area of the current primary jets.
Add the two areas together.......calculate what size hole that equates to..... install jets with that size hole.
That’s as good of a starting point as you can get without wet flowing the carb.
You should check the gasket surface for flatness on the front and rear of the main body.
I’ve seen them pretty warped in the past, which caused all kind of problems with several aspects of the carb function.
“Back in the day”........ when we’d send carbs out to have them “done”, milling those surfaces was always part of the process.
The PV gets its signal from that hole at the bottom of the cavity, into a hole in the baseplate,(just like yours), but the hole in the typical “universal carb” baseplate has a little “v” channel to get vacuum when the 4 hole gasket is used(see pic).
I don’t know what I was thinking about with the cavity in the center of the carb and the PV
(Looking at your pic with the 4 hole gasket in place...... it still doesn’t appear as though the gasket “sealed off” that front cavity.
It would only need a leak with as much area as the size of the hole from the base into the PV cavity).
You sure those extra screw threads from the bottom aren’t interfering with how the PV slides into the cavity?
You could still try plugging the PV.
Measure the PVCR, calculate the area.
Calculate the area of the current primary jets.
Add the two areas together.......calculate what size hole that equates to..... install jets with that size hole.
That’s as good of a starting point as you can get without wet flowing the carb.
You should check the gasket surface for flatness on the front and rear of the main body.
I’ve seen them pretty warped in the past, which caused all kind of problems with several aspects of the carb function.
“Back in the day”........ when we’d send carbs out to have them “done”, milling those surfaces was always part of the process.
Posted By: fast68plymouth
Re: Removing power valve - 06/07/19 08:47 PM
Make sure the metering block gasket looks like it’s not leaking around the “tube” that feeds the accelerator pump nozzle.
On your carb it appears to be a cast “standpipe”.
The more common arrangement was to have some of the top of the cavity filled in that area, which provided a broader area of support for the gasket.
You may want to verify that you’re using the “correct” metering block gasket, or at least see if it uses a generic gasket or something a little more specific to that carb.
On your carb it appears to be a cast “standpipe”.
The more common arrangement was to have some of the top of the cavity filled in that area, which provided a broader area of support for the gasket.
You may want to verify that you’re using the “correct” metering block gasket, or at least see if it uses a generic gasket or something a little more specific to that carb.
Posted By: varunner
Re: Removing power valve - 06/07/19 09:40 PM
Thanks Dwayne, I will continue to measure and inspect this bad boy. Another carb will be here in 2 weeks, so I'll be able to swap it out.
cheers
cheers
Posted By: varunner
Re: Removing power valve - 06/09/19 04:30 PM
Think I've fixed this issue. Gaskets were leaking bad on both ends. I re-surfaced both ends of the body where the fuel bowels go. Amazing how bad a shape they were in once I started working on them. I will never build a carb without doing this. I also plugged the vacuum port in the vacuum space as a test in case it was still leaking. The vacuum space is dry on both ends now and spark plugs are also dry. Still a little fuel in the intake, not going to worry any more about that. I'll see how it runs. On to the next problem..
.jpg "20190608_174419_1560030352815_resized (2).jpg")
Posted By: fast68plymouth
Re: Removing power valve - 06/09/19 06:22 PM
If you plugged the vac port to that cavity....... the PV def won’t work like that.
You going to try it without one?
When is the next outing?
Got your nhra number yet?
You going to try it without one?
When is the next outing?
Got your nhra number yet?
Posted By: varunner
Re: Removing power valve - 06/09/19 08:43 PM
The plug was only in there as a test in case the re-surfacing didn't work. It's out now. I also put the PV back in. I do a final test tomorrow. VMP has an all day TnT next friday, planning on running that. #1358 G/SA
Posted By: fast68plymouth
Re: Removing power valve - 06/09/19 09:11 PM
Good luck at the TnT.
G/SA......12.00 index.
Shouldn’t be too hard to get it to go .40-.50 under.
I don’t know what your best speed has been so far(of course, I’m sure the carb hasn’t worked right on any passes)........ but I’d say you’re looking for 113+.
You said it had 60’d a 1.50 already....... so that part seems good.
Too bad that carb situation wasn’t sorted out before the motor was on the dyno.
G/SA......12.00 index.
Shouldn’t be too hard to get it to go .40-.50 under.
I don’t know what your best speed has been so far(of course, I’m sure the carb hasn’t worked right on any passes)........ but I’d say you’re looking for 113+.
You said it had 60’d a 1.50 already....... so that part seems good.
Too bad that carb situation wasn’t sorted out before the motor was on the dyno.
Posted By: varunner
Re: Removing power valve - 06/09/19 10:34 PM
Thanks, appreciate the help.
I just added 115 lbs to make G weight.
So I have only made 12 passes total since the motor/car was finished. I'm lucky enough to have 3 tracks within 2 hrs, VMP, MIR, and RD, but we're had a bunch of rainouts.
Best pass was 11.79/111 at MIR, 1.56 60ft.
I had a 1.50 60ft at VMP, with a 15 mph headwind, 1/8th mile et was the same as what I did at MIR.
I have 2 goals before August when 3 divisionals happen, Galot, VMP, and the rock.
1) get the carb jetting close. I have read somewhere, wish I could find it again, that with this intake the carb needs to be staggered jetted. I think I read that in an old mopar book, wish I could find that.
2) decide on if I foot-brake it or 2-step. Most people say and I agree it will be faster foot-braking it. I think I will be more consistent on the starting line with the 2-step. so the question is how much difference will there be. If it's a couple tenths, great, foot-brake it is. If it's .05 then I'll stay with the 2 step. This could take a while.
I just added 115 lbs to make G weight.
So I have only made 12 passes total since the motor/car was finished. I'm lucky enough to have 3 tracks within 2 hrs, VMP, MIR, and RD, but we're had a bunch of rainouts.
Best pass was 11.79/111 at MIR, 1.56 60ft.
I had a 1.50 60ft at VMP, with a 15 mph headwind, 1/8th mile et was the same as what I did at MIR.
I have 2 goals before August when 3 divisionals happen, Galot, VMP, and the rock.
1) get the carb jetting close. I have read somewhere, wish I could find it again, that with this intake the carb needs to be staggered jetted. I think I read that in an old mopar book, wish I could find that.
2) decide on if I foot-brake it or 2-step. Most people say and I agree it will be faster foot-braking it. I think I will be more consistent on the starting line with the 2-step. so the question is how much difference will there be. If it's a couple tenths, great, foot-brake it is. If it's .05 then I'll stay with the 2 step. This could take a while.
Posted By: fast68plymouth
Re: Removing power valve - 06/10/19 12:17 AM
You should try the weight in and out at the TnT, since which way is farther under.
Both F and G have a ton of cars....... but I think G has more.
Depending where on the ladder you are..... .05 can be a few spots on the sheet.
My advice on the jetting is...... get something like an Autometer A/F gauge in the car, so you can keep track of what does what with the jetting.
Both F and G have a ton of cars....... but I think G has more.
Depending where on the ladder you are..... .05 can be a few spots on the sheet.
My advice on the jetting is...... get something like an Autometer A/F gauge in the car, so you can keep track of what does what with the jetting.