Previous Thread
Next Thread
Print Thread
Page 2 of 5 1 2 3 4 5
Re: My new heads are killing me need help [Re: 70dusterjohn] #2538726
08/19/18 10:30 PM
08/19/18 10:30 PM
Joined: Jan 2003
Posts: 20,149
Park Forest, IL
slantzilla Offline
Too Many Posts
slantzilla  Offline
Too Many Posts

Joined: Jan 2003
Posts: 20,149
Park Forest, IL
Any chance the relief is stuck in the fuel pump? I had that happen once and it would never show a symptom until you tried to launch the car at the track.


"Everybody funny, now you funny too."
Re: My new heads are killing me need help [Re: B3422W5] #2538741
08/19/18 10:57 PM
08/19/18 10:57 PM
Joined: Feb 2005
Posts: 4,309
Prospect, PA
BSB67 Offline
master
BSB67  Offline
master

Joined: Feb 2005
Posts: 4,309
Prospect, PA
Originally Posted By B3422W5
Originally Posted By Locomotion
* Jet for MPH.
* Squirters & pump cams for 60'

Be careful so one doesn't overlap the other. (i.e.: too much jet can mask a need for bigger squirters and/or a bigger (longer squirting) pump cam.

Smaller squirters will increase the duration of the squirt and bigger squirters will shorten the duration of a given pump cam. You don't want the squirt any longer or shorter than necessary because it will mess up the A/F ratio of the main metering system (jets).


Yep. All that stuff contributes to optimal ET’s. But his car is off 8 tenths or more.


I'm with you. His problem is not jets and squirters.

How many mph is it off?

I would be looking for something bigger that was touched when in the motor. twocents

Re: My new heads are killing me need help [Re: 70dusterjohn] #2538861
08/20/18 06:17 AM
08/20/18 06:17 AM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
Well it’s coming back out. I really didn’t to have to pull it again but it is what it is I guess.

Re: My new heads are killing me need help [Re: BSB67] #2538863
08/20/18 06:19 AM
08/20/18 06:19 AM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
It’s off over 20 mph was running 140 ish and 120 to 124 was the beat

Re: My new heads are killing me need help [Re: 70dusterjohn] #2538877
08/20/18 08:58 AM
08/20/18 08:58 AM
Joined: Nov 2003
Posts: 1,825
NW Indiana
F
fbs63 Offline
top fuel
fbs63  Offline
top fuel
F

Joined: Nov 2003
Posts: 1,825
NW Indiana
The cam is big duration wise for 11.1 compression. You check cranking compression?

Re: My new heads are killing me need help [Re: 70dusterjohn] #2538885
08/20/18 09:28 AM
08/20/18 09:28 AM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
Yeah was all between 170-175 was the highest ..

Re: My new heads are killing me need help [Re: 70dusterjohn] #2538886
08/20/18 09:30 AM
08/20/18 09:30 AM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
But again the only change made was the porting of the heads and intake ..

Re: My new heads are killing me need help [Re: 70dusterjohn] #2538899
08/20/18 10:30 AM
08/20/18 10:30 AM
Joined: Nov 2003
Posts: 1,825
NW Indiana
F
fbs63 Offline
top fuel
fbs63  Offline
top fuel
F

Joined: Nov 2003
Posts: 1,825
NW Indiana
You run pump gas?

Re: My new heads are killing me need help [Re: 70dusterjohn] #2538927
08/20/18 11:25 AM
08/20/18 11:25 AM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
No I run 110 race fuel

Re: My new heads are killing me need help [Re: 70dusterjohn] #2538933
08/20/18 11:37 AM
08/20/18 11:37 AM
Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
Have It dynoed........ figure out if it’s the motor combo, an accessory(fuel pump, ign, carb), or something else in the car(converter, wiring, etc).

If the motor makes the expected power, you can rule that out and focus on the other stuff.

I’d bring my carb and ign box with me if you get it tested.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Re: My new heads are killing me need help [Re: 70dusterjohn] #2539260
08/20/18 09:12 PM
08/20/18 09:12 PM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
Well I just pulled the motor for the 4th time this season and I can tell you it’s getting old pulling a B.B. out of an a-body. I noticed that the exhaust looks all sooted up. I think I have my carb space on backwards so not sure what that will do. Then I got busted tell on my converter and can’t seem to find anyone to fix it so I Guess I will weld them up and try it all again. I don’t know what else to do ???

Re: My new heads are killing me need help [Re: 70dusterjohn] #2539264
08/20/18 09:22 PM
08/20/18 09:22 PM
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Dodgem Offline
master
Dodgem  Offline
master

Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Id put the jets back to last year. then check Cam degree!

Re: My new heads are killing me need help [Re: 70dusterjohn] #2539302
08/20/18 10:32 PM
08/20/18 10:32 PM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
Done and done ... nothing seems to make a difference

Re: My new heads are killing me need help [Re: 70dusterjohn] #2539308
08/20/18 10:50 PM
08/20/18 10:50 PM
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Dodgem Offline
master
Dodgem  Offline
master

Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Your sure the mark on the balancer is right?? leak down and compression test maybe it is hitting the valves?
so does it just lie down right off the line? Valves are not marking pistons. no missing just flat??


Last edited by Dodgem; 08/20/18 10:56 PM.
Re: My new heads are killing me need help [Re: 70dusterjohn] #2539312
08/20/18 11:02 PM
08/20/18 11:02 PM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
Everything looks new, it’s got 2 runs on a fresh rebuild .. no idea what’s up. I have a set of stock max wedge heads I was thinking of throughing them on to see if there is a difference..

Re: My new heads are killing me need help [Re: 70dusterjohn] #2539329
08/20/18 11:23 PM
08/20/18 11:23 PM
Joined: Jan 2003
Posts: 30,947
Oregon
A
AndyF Online content
I Win
AndyF  Online Content
I Win
A

Joined: Jan 2003
Posts: 30,947
Oregon
Sometimes you need a fresh set of eyes on a problem like that. Do you know any engine builders who will take a look at the engine with you? Sounds like you're missing a bunch of power so it has to be something fairly big. It could be the convertor or the trans too. Those things can kill your ET if they go bad. Heck, one time I lost a bunch of power because my emergency brake got partially locked up. Took me a while to figure that one out!

Re: My new heads are killing me need help [Re: 70dusterjohn] #2539567
08/21/18 01:48 PM
08/21/18 01:48 PM
Joined: Aug 2003
Posts: 43,007
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 43,007
Bend,OR USA
When a car slows down after a parts change their is a reason for that change, figuring out what is causing it can be the hard, challenging part work
Reading your other post about the converter I would look very hard at that, those teeth don't break normally work scope
Converters die and get worn out shruggy


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: My new heads are killing me need help [Re: 70dusterjohn] #2539790
08/21/18 10:36 PM
08/21/18 10:36 PM
Joined: Feb 2005
Posts: 4,309
Prospect, PA
BSB67 Offline
master
BSB67  Offline
master

Joined: Feb 2005
Posts: 4,309
Prospect, PA
Maybe I missed it, but have you told us all of the stuff you did check? Might be easier than us guessing what it could be.

Looks like your missing about 200 hp.

First thoughts:
If the car has mufflers, something sh** the bed there
What's your trap fuel pressure?
Cranking cylinder pressure?
Cylinder leak down?
Converter sh** the bed
Fuel line problem between gauge and carb
Cam timing off
Ignition timing way off
lost lobe

I know in the past that I have been so convinced that something was right that I could not see that it was not.

Re: My new heads are killing me need help [Re: 70dusterjohn] #2539956
08/22/18 11:35 AM
08/22/18 11:35 AM
Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
70dusterjohn Offline OP
top fuel
70dusterjohn  Offline OP
top fuel

Joined: Aug 2006
Posts: 1,613
Deerfield, Ohio
No the converter issues happened long ago and I just kept welding teeth on it but it’s getting to messed up to keep it up.
Checked wiring
Checked timing
Checked comp test 170-175
Checked leak down was not a noticeable difference
Checked cap and rotor
Checked crank trigger
Checked ignition box/ tried my 7al
Trans temp is good. I just don’t know where else to look

Re: My new heads are killing me need help [Re: 70dusterjohn] #2539971
08/22/18 12:17 PM
08/22/18 12:17 PM
Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
F
fast68plymouth Offline
I Live Here
fast68plymouth  Offline
I Live Here
F

Joined: Jan 2003
Posts: 14,479
So. Burlington, Vt.
This is a good example of why if someone brings me a motor with the intent of me making a few changes to increase the power output....... it gets put on the dyno before being taken apart.

This does two things(for a drag application).....
-establishes a baseline number to work from.
-helps determine if the “car” is running the et’s it should for the power the motor currently makes.

I’ve seen it go both ways before.
-The car was slow, but the motor was doing exactly what it should...... so no changes were made to the motor......... and the customer diligently worked on the car and ultimately picked up over .5 ET without making any more power.
-The car was slow...... and the motor was down a solid 50hp from what I was getting from very similar combos.

Of course, then there’s the situation where someone buys a motor that came with a dyno sheet, and the car hasn’t been running et’s or speeds representative of the dyno numbers are....... and they have spent thousands on fuel system upgrades, trans parts, converters, maybe some gears, etc....... all to no avail.
Then we put it on the dyno and it’s down 50, 75, 100hp from what the dyno sheet that came with the motor shows......... and the car is going exactly as fast as it should, based on our numbers.
It’s this scenario that lead me to start testing before any modifications begin....... to make sure everyone is on the same page right from the start.

The OP’s car is running way way off from what it should.
It shouldn’t be that hard to come up with a realistic horsepower estimate for that combination of parts.
If the motor makes within +/- 30hp of that figure....... you can leave the motor combo alone........ it’s not your problem.
On the other hand, if it’s down 100hp....... better get it apart and start looking.

Obviously, you’d like to test at a dyno service that has a good history of cars running times/speeds that are in line with what’s expected based on the dyno numbers.


68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
Page 2 of 5 1 2 3 4 5






Powered by UBB.threads™ PHP Forum Software 7.7.1