Moparts

I just lit the 431 stealth headed stroker off...issues

Posted By: mopar_leaner

I just lit the 431 stealth headed stroker off...issues - 10/17/13 04:27 AM

so I fired up the 431 and it seems to run hot, Im not sure on the set up for the MSD distributor as far as springs and bushing. Currently I a heavy and light silver and the blue bushing. I have a champion radiator with the shroud and 10" fans.
The cam is a voodoo .513 hydraulic lifters. RPM intake with a 800 AVS carb. and StreetFire box and wires+Chamions RC12Y.....stock Magnum exhaust manifolds.
Posted By: RobX4406

Re: I just lit the 431 stealth headed stroker off...issues - 10/17/13 04:31 AM

Take the garage door spring off. Use the two light blues or a light silver and blue spring.

That garage door spring will play havoc with getting timing in if you are breaking in a camshaft.

Black 18* bushing too... I have other bushing that go to 10 and 14* mechanical; timing if you need more initial
Posted By: mopar_leaner

Re: I just lit the 431 stealth headed stroker off...issues - 10/17/13 05:34 AM

thank you so much for the help, I will change the curve in it tomorrow.
Posted By: RapidRobert

Re: I just lit the 431 stealth headed stroker off...issues - 10/17/13 02:11 PM

For breakin make a mark 2&1/4" to the right (clockwise) of the TDC slit on the dampener & when it fires have a helper with the light turn the dist housing till the new mark lines up with the zero on the timing tab which is 35.5 degrees (vac adv capped). This'll work good & is easy/trouble free to do for the 2500 rpm breakin. Also need the stat out (for breakin) & a shop fan in front. I dont think you have enough airflow
Posted By: feets

Re: I just lit the 431 stealth headed stroker off...issues - 10/17/13 08:05 PM

Cheap 10" fans with tight shrouds can cause more heating problems than they solve.

Good luck.
Posted By: mopar_leaner

Re: I just lit the 431 stealth headed stroker off...issues - 10/18/13 05:43 PM

I change the curve in the dist. and it seems to run much cooler. The weird thing is, it idles good before the choke open all the way, the idle goes up.
But an even bigger problem is oil leaking from the back of the engine. So out with the engine.
Also the exhaust on this car is from the mid 80's, 2-1/4 scab pipe with glass packs.
Posted By: ScottSmith_Harms

Re: I just lit the 431 stealth headed stroker off...issues - 10/18/13 06:03 PM

Sounds like you have (at least) a vacuum leak somewhere.
Posted By: mopar_leaner

Re: I just lit the 431 stealth headed stroker off...issues - 10/19/13 06:58 AM

very possible on the vacuum leak. I just pulled the engine and changed out the cam plug and looks like oil leak is gone.
now I'm wondering if the 800 AVS might be to big.
Posted By: dogdays

Re: I just lit the 431 stealth headed stroker off...issues - 10/21/13 04:57 PM

NO! The 800 AVS isn't too big, for this reason: Air Valve Secondary. That's what the AVS stands for.

With any air valve carb, what you have is basically the front two barrels plus whatever the engine's demand is from the secondaries. The air door tailors the carb size to the actual engine needs.

This is why those Thermoquads worked so well, and why my Mercedes 170 cubic inch six has a German copy of a Quadrajet sitting on its intake.

Q-jet, Thermoquad, AVS all have air doors. I believe AFBs have them too but they're hidden deeper in the carb and aren't externally adjustable. Holley vacuum secondary carbs do the same thing, but with the vacuum pod opening the secondaries as needed.

R.
Posted By: mopar_leaner

Re: I just lit the 431 stealth headed stroker off...issues - 10/22/13 01:30 PM

ok, makes sense. I am a holley guy, but more and more I have been using the Edelbrocks as they don't need as much tinkering once you get them dialed in.
I have jumped over most of my hurdles, thank you guys so much for all your help.
Posted By: mopar_leaner

Re: I just lit the 431 stealth headed stroker off...issues - 10/22/13 01:32 PM

any ideas for spark plug gap with 190 psi of cylinder pressure and the MSD StreetFire box?
Posted By: jbc426

Re: I just lit the 431 stealth headed stroker off...issues - 10/25/13 03:55 PM

Quote:

any ideas for spark plug gap with 190 psi of cylinder pressure and the MSD StreetFire box?




.040 is probably close, but maybe a better question is where do they sell race gas in your neighborhood. That's a lot of cranking compression for pump gas.
Posted By: mopar_leaner

Re: I just lit the 431 stealth headed stroker off...issues - 10/26/13 11:53 PM

now for the latest problem......the rear main is leaking!!! what is the best way to make sure this doesn't happen again?
© 2024 Moparts Forums