Previous Thread
Next Thread
Print Thread
Page 2 of 2 1 2
Re: Cam too big? [Re: cornet684me] #612137
02/13/10 01:44 PM
02/13/10 01:44 PM
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Dodgem Offline
master
Dodgem  Offline
master

Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Did you check the float levels. should have a 6.5 power valve and 70 to 72 front jets.

Re: Cam too big? [Re: Dodgem] #612138
02/13/10 01:52 PM
02/13/10 01:52 PM
Joined: Dec 2007
Posts: 1,639
Brandon, Ms
C
cornet684me Offline OP
top fuel
cornet684me  Offline OP
top fuel
C

Joined: Dec 2007
Posts: 1,639
Brandon, Ms
yes, the floats are fine, the carb. did have a 6.5 power valve, i have replaced with 3.5, i was going to take apart and go down with the jets,
i am going to try this next week, a buddy just called he will bring me a good dist. that he has to let me try to see if is my dist.

Re: Cam too big? [Re: cornet684me] #612139
02/13/10 02:39 PM
02/13/10 02:39 PM
Joined: May 2005
Posts: 416
Franklin Co. Illinois
runinonmt Offline
mopar
runinonmt  Offline
mopar

Joined: May 2005
Posts: 416
Franklin Co. Illinois
Quote:

power valve gasket-not only for tears but position on the power valve

what do you mean the position of the power valve?
i did replace the power from 6.5 to 3.5 with a new one



I have seen power valves with the gasket off center sitting on the step allowing a leak.
While you're atit make sure the floats aren't heavy from a leak,the air filter is clean and that the hood insulation isn't blocking air to the carb. This actually happened to a friend.I won't mention any names.
Ron

Last edited by runinonmt; 02/13/10 03:15 PM.
Re: Cam too big? [Re: runinonmt] #612140
02/13/10 03:19 PM
02/13/10 03:19 PM
Joined: Nov 2006
Posts: 1,456
oklahoma
F
forphorty Offline
pro stock
forphorty  Offline
pro stock
F

Joined: Nov 2006
Posts: 1,456
oklahoma
Quote:

Quote:

power valve gasket-not only for tears but position on the power valve

what do you mean the position of the power valve?
i did replace the power from 6.5 to 3.5 with a new one



I have seen power valves with the gasket off center sitting on the step allowing a leak.
Ron


Yep, the old gaskets had tabs to locate it, i believe. Don't think any of the new ones do. I like to hold the metering block flat when installing the PV.

Re: Cam too big? [Re: cornet684me] #612141
02/13/10 05:20 PM
02/13/10 05:20 PM
Joined: Mar 2007
Posts: 3,277
West Coast, USA
jbc426 Offline
master
jbc426  Offline
master

Joined: Mar 2007
Posts: 3,277
West Coast, USA
First things first. What do you have you timing set at, initial and total?


1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's
1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)
Re: Cam too big? [Re: jbc426] #612142
02/13/10 08:22 PM
02/13/10 08:22 PM
Joined: Nov 2004
Posts: 1,760
Port Alberni, British Columbia
MoparDonny Offline
top fuel
MoparDonny  Offline
top fuel

Joined: Nov 2004
Posts: 1,760
Port Alberni, British Columbia
Without a dial-back light, just set the initial timing (at 900ish RPM) to about 14 degrees, then set the mixture screws to about 2.5 or 3 turns(or just set them properly if you know how) finally check the float level once more and once the fuel just comes out of the sight plugs, go back down a 1/4-1/2 a turn. Keep at it, my 383 with 8:1, 800 Double pumper and a MP 274 cam was running mid to high 13's and ran unreal.

Don.

Re: Cam too big? [Re: MoparDonny] #612143
02/13/10 10:17 PM
02/13/10 10:17 PM
Joined: Dec 2003
Posts: 5,314
Carstairs, Alberta, Canada
dave571 Offline
master
dave571  Offline
master

Joined: Dec 2003
Posts: 5,314
Carstairs, Alberta, Canada
A couple of things.

What you are describing is typical of a low comp engine with a larger cam and not enough intiial timing. You can jet it all day, if you like. But it won't run any better till the timing is sorted out.

.050 off the heads of a motor with the pistons .170 in the hole, doesn't do much. It'll be 8:1 on a good day.

Ideally, I think you want to advance that cam 4 degree's or so to make it better down low..

The rock stock converter isn't doing you any favors. The misconception is that you can't drive a converter with more stall on the street.
A well built performance converter will drive like a stocker under light throttle, and flash to a higher rpm on hard launch. A 3K converter would be a nice match for that.

If I was curving a distributor for you, I'd recommend 18 intial, and 35 total all in by 2800.

The 3.55's are fine. I run way more cam with 3.73's, and didn't lose any ET when I switched from the 4.10's I had before the 3.73's.

Re: Cam too big? [Re: cornet684me] #612144
02/14/10 12:07 AM
02/14/10 12:07 AM
Joined: Apr 2005
Posts: 12,271
Overpriced Housing Central
RobX4406 Offline
I Live Here
RobX4406  Offline
I Live Here

Joined: Apr 2005
Posts: 12,271
Overpriced Housing Central
Quote:

i cannot figure out where the timing is, however, i know the timing is not the issue here




ummmm, yeah ok... yet it's fuming you out...

If you give the engine more initial advance does it pick up RPM?

That cam should idle below 1000rpm.

I wonder if you turn the idle down you get a drop in timing. Mechanical being bled in at a low RPM. Happens all the time.

The carb is running on the transfer slots, that's part of the reason it's fuming you out.

If you don't have a timing tape, do a hillbilly timing tape. With the timing mark on the pass side, turn the balancer line to the bottommost indicator mark, mark a line 15* towards the top of balancer, turn the new marked line down to the lowest tab mark and make another mark 15* up. Now you can get the timing set in a range to about 45* BTDC.

DO NOT set the car using the total timing method. Set it by most vacuum/constant rpm, starter kickback or advancing until it no longer pick up RPM/resetting to constant. Somewhere in the 16-22* range should work. Shoot for an idle rpm of 900 in park.

Baseline the carb at 1.5 turns out on the idle mix screws. Start over.

DO NOT be concerned with total timing now. That's the second piece of the puzzle.

Re: Cam too big? [Re: RobX4406] #612145
02/14/10 01:31 AM
02/14/10 01:31 AM
Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
DaytonaTurbo Offline
Too Many Posts
DaytonaTurbo  Offline
Too Many Posts

Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
Like I said before timing affects fueling, fueling does not affect timing get that timing setup correctly initial AND total before you even dink around with the carb. Until you do that you are wasting your time. I run a 76 440 with stock pistons and the lunati 60303 cam which is 226/234 @ 050 to your 230/236 not much difference. Mine runs/drives just as cleanly as it did with the stock lo-po cam which is said to be more like 210. This combo loves a well tuned distributor, you can NOT just bolt one in right out of the box and go. Mine likes 18* initial, maybe more yet, but I had been running it (needlessly) on pump 94. You will want a lot of initial timing like that, with the total near 40 all in somewhere around 2500. You need either a dial back timing light or timing tape for your balancer. Once that distributor is dialed in, then and only then start to tinker with the carb. Without the correct timing, you will not be able to tune out that bad bog when you snap to WOT nor will you get any kind of a clean burn.

Re: Cam too big? [Re: cornet684me] #612146
02/14/10 01:34 AM
02/14/10 01:34 AM
Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
DaytonaTurbo Offline
Too Many Posts
DaytonaTurbo  Offline
Too Many Posts

Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
Quote:

so what you are saying is, with some tuning , i should be able to make this set up work, i have the motor in a 1968 dodge coronet, 727 with stock covertor and i have 3.55 gears,




Stock converter is doing you no favors, and the 3.55 gears are marginal but doable. The problem with the stock converter is you're only going to get a 2000rpm flash out of it and your motor is going to be soggy and not respond the best when you snap to full throttle and the motor is not able to flash stall to above the rpm where your total timing is in at. The smogger CR motors are more sensitive to the correct balance of timing and stall than this same cam in a 10:1 440 would be.

Re: Cam too big? [Re: DaytonaTurbo] #612147
02/14/10 02:08 AM
02/14/10 02:08 AM
Joined: Dec 2003
Posts: 5,314
Carstairs, Alberta, Canada
dave571 Offline
master
dave571  Offline
master

Joined: Dec 2003
Posts: 5,314
Carstairs, Alberta, Canada
Quote:


Stock converter is doing you no favors,






quoting me
Quote:


The rock stock converter isn't doing you any favors.




Great minds think alike...LOL


Quote:

The smogger CR motors are more sensitive to the correct balance of timing and stall than this same cam in a 10:1 440 would be.




For sure. The lower comp makes for a lazy burn. Needs more timing sooner, to compensate.

Re: Cam too big? [Re: cornet684me] #612148
02/14/10 02:26 PM
02/14/10 02:26 PM
Joined: Apr 2003
Posts: 551
Colo Springs, Co
D
dragaddict Offline
super street
dragaddict  Offline
super street
D

Joined: Apr 2003
Posts: 551
Colo Springs, Co
Run a combo not too far off and found that the MSD box with Blaster coil really helped to clean it up. Everything else has a compromise such as bigger carb is more power less milage, bigger cam is higher rpm to get to usable range. Beter ignition is win/win better per Dr Jacobs. Starting,running,milage and cleaner burn. I also had a problem with an incorrect ballast resistor on a coil-distributor that took some life out of me before we found it. One system at a time works for me.

Re: Cam too big? [Re: dave571] #612149
02/14/10 02:32 PM
02/14/10 02:32 PM
Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
DaytonaTurbo Offline
Too Many Posts
DaytonaTurbo  Offline
Too Many Posts

Joined: Feb 2003
Posts: 21,318
Manitoba, Canada
Quote:



Great minds think alike...LOL




Lol or frozen minds!

Re: Cam too big? [Re: dragaddict] #612150
02/14/10 02:44 PM
02/14/10 02:44 PM
Joined: May 2005
Posts: 2,295
dark side of the moon
D
Dougsmopars Offline
top fuel
Dougsmopars  Offline
top fuel
D

Joined: May 2005
Posts: 2,295
dark side of the moon
A lot of people are afraid of stall converters. I have a 28 to 3200 stall cars drives like any other car till you mash the pedal. No banging when you drop into gear no 2 footing at a red light to keep it from stalling. Back in the 80's i had a 69 Charger 440 525"lift 290 310 advertised duration 12.5 to 1 tunnel ram motor 4;10 gears and a 5000 stall. That would stall a bit higher just driving around but not that much more then a stock converter. It was very drivable. But it was fun when you mashed that pedal.

Re: Cam too big? [Re: cornet684me] #612151
02/16/10 12:34 AM
02/16/10 12:34 AM
Joined: Dec 2007
Posts: 1,639
Brandon, Ms
C
cornet684me Offline OP
top fuel
cornet684me  Offline OP
top fuel
C

Joined: Dec 2007
Posts: 1,639
Brandon, Ms
wow, thanks for all the input, from what i am reading, sounds like i need to get someone over to my house to teach me about timing, i have tried all the tricks everyone is saying, i have marked top dead center, put timing tape 2 1/4" and 1", the problem is i cannot get the car to run correctly trying to do this by the book timing, when i try to do by the book, the car runs like crap, then i hook up the vac. gauge and do it by ear and feel, i get the car running great, except for the flumes out the exhaust, i am going to break down and load it up on trailer and take it to expert in timing next week, i will give Moparts update, everyone has told me the problem is in the Timing, and the only reason i avoided it , is because i really do not know anything about getting this done, i was hoping to put some jets in carb and fix it, i should have known , this wld be too easy, Thanks for everyone's thoughts and input, i really think it is the timing too, i think i am running 18 to 20degress at idle, i cannot figure out the total timing yet, i have been just trying to do the timing by ear, vac. gauge and feel, starter drag etc., i guess this old shade tree trick is not going to work with a high performance cam, i will get back with Moparts once i try to get the timing thing sorted out!

Re: Cam too big? [Re: MoparDonny] #612152
02/17/10 01:00 AM
02/17/10 01:00 AM
Joined: Jan 2003
Posts: 4,395
The Pale Blue Dot
Skeptic Offline
master
Skeptic  Offline
master

Joined: Jan 2003
Posts: 4,395
The Pale Blue Dot
If you didn't index the cam, the cam could be off and you'll chase your tail trying to tune it out. Just lining up the dots isn't good enough for aftermarket parts.

Page 2 of 2 1 2






Powered by UBB.threads™ PHP Forum Software 7.7.1