[strokerchevyII]

383 stroker question

I'm new to this forum but i just hope that someone can help me out. I've built a 383 stroker and it's in my 1966 Chevy II Nova, everything was running just fine had the typical problems with a build engine, but i've run in to a problem that i just cant figure out. The engine starts perfectly, and idols just fine and as soon as i get to around 2500 RPM's it just die's. Thought that it was the MSD that I was running and that it wasn't getting direct power so we wired it to a toggle switch and now it has constant power, but it still is acting like it's loosing spark or fuel. It acts like i just turn the key off. So we completly replace the distributor and everything and just decided not to run the MSD and I still have the same problem. I am totally out of idea's i can get a complete part list to see if maybe something that i'm running might be the problem, but any help would be greatly appreciated.

 

[Centerline]

If you've eliminated the ignition as a problem your only other logical source is fuel. Are you running a carb or fuel injection? What kind of pump/fuel lines are you running? Do you have a fuel pressure gauge installed?

My guess is a fuel starvation problem.

Centerline

 

[DoubleVision]

Once it goes dead, remove the air cleaner and shine a light in the carbs throat, move the throttle and see if fuel comes out of the accelerator pump shots, if you see no fuel you found the problem, it`s also possible it could be vapor locking, is the fuel line/filter close to the engine or any other high heat source? what kind of pump are you using and where is it located?

 

[strikingthematch]

***EDIT*** Well I see you removed the dis. and it still does the same thing. In that case see if you can watch your carb just move push on the gas a little ( at side of carb.) there might be something getting caught or the fuel not shotting in correctly. Just do this with the air cleaner off and try to watch everything very closely.

***ORG post***
Do you have an MSD 6AL with rev limiter. If so the little white chip could have the 2000 rpm chip in it and since it is a soft touch limiter it would act like it's loseing spark and or fuel. Just a thought if you just installed it. Good luck.


Chris

 

[roys63]

Have you checked the carb float level? if you have a Holley this is very easy.

 

[strokerchevyII]

We are running a carborated system not fuel injected, fuel pump and filter is located in the truck and we are also running a racing fuel cell. Have already adjusted the floats many times, running steel braided fuel lines with a fuel pressure regulator running 6psi. We just recenetly installed a new holley 850 double pump carb. Should the fuel cell be vented? It backfires though that carb after we try to start it directly after it dies. Should we try to run the car with out the cap to see if that would help with the venting of the cell. Cause this cell is a 14gal RCI racing cell and it has a locking cap with a boot. We are not sure if this is the problem or what, but every little bit of help would be greatly appreciated. Thanks

 

[Max Keith]

383 stroker

There are two things that come to mind here. Bad power valve, or jetted way too lean. If you have a choke, try closing it half way. If you continue to have the problem, then I would look at the power valve. Your cap probably is vented, otherwise your engine would die on you even after idling for some time. Since you are running a double pumper, you might also check your secondaries for fuel flow as well.

 

[Centerline]

Should the fuel cell be vented?

Absolutely. The fuel cell should have a vent line run from the top of the cell back through the floor venting under the car and it should be equipped with a anti roll over valve. For now try running the engine with the cap off to see if that solves your problem. Even if it doesn't install a vent in the tank.

In the photo below you can see a typical fuel cell installation. The braded stainless steel vent line exits the top of the tank and runs down through the floor. The fuel outlet is at the bottom center of the tank and is also braded stainless steel.

Centerline

 

[strokerchevyII]

we did find vent in the fuel tank, pulled all the fuel lines and cleaned them out and the carb has an option that we can not blow the power valve out. It has the jets that came with it out of the box. It is still back firing out of the carb.

 

[paulo]

Try running a timing light full time as you rev the engine.Simple way to see that you are runnning out of sparks or not.

 

[1BAD80]

Backfiring thru the carb can be a few things.
The carb is out if it squirts, Timing, wires on wrong or jumping spark, to tight of a valve lash or the wrong vibration damper / timing marker.
Sounds like its retarded a couple of teeth.
My .002 cents.

 

[strokerchevyII]

We are running chain gears and is anyone running these and did you adjust them to top dead center or did you retard or advance it any. But we got it started and it is running great needs to be tuned a bit, but we found a problem the floats on the carb were not set right and there was something wrong with the back jets so we fixed that problem and everything is working fine now, but I just want to thank everyone for their advice and i really appreciate everyone's help. Once again thanks alot.