[strays]

I've just installed a 350 crate engine in my '69 pick up. Timing is at 8 degrees without vaccuum advanced hooked and plugged off. with it hooked up it is about 1/2" passed the timing marks, putting it around 14 to 16. wires are brand new and in correct order, with the very least amount of crossing near the cap. None touching each other. rest set idle and carb screws are at 2 1/2 turns out. Exhaust is very short, comes out right behind the cab for now. Running electronic ignition and the quadra jet carb. Need help because I do not want to blow another engine for possible timing issues. Any help or ideas are appreciated.
Thanks,
Strays

 

[DoubleVision]

Is the ignition getting 12 volts? HEI`s must have 12 volts to operate correctly If not it`ll backfire.

 

[cobalt327]

Timing is at 8 degrees without vaccuum advanced hooked and plugged off. with it hooked up it is about 1/2" passed the timing marks, putting it around 14 to 16.

You also need to know what the TOTAL timing is, w/o ther vac advance adding anything. Knowing this figure is what can help keep you out of detonation.

If you don't have an advance timing light, MAKE a timing tape to see what you have.

There is another very good tutorial on finding true TDC HERE, in the event that your timing marks might be off due to mismatched timing tab/damper marks.

Shoot for no more than 36 degrees if non Vortec or non fast-burn type heads, 32 degrees if they are. Adjust to optimum from these figures.

 

[strays]

thanks alot. will check the voltage and timing marks. Having a feeling that is the problem. I'll keep you update!

 

[strays]

ok.. TDC has been located on balancer.. about 1/2" off.. but it is popping when reving it up small amouts.. throtle tap.. but starts pretty smooth.. timing is about 10 cause 8 was still a little rough without vaccuum hooked up

 

[56Maynard]

Intake leak?

 

[strays]

have not been able to find one.. running rich by color and smell of exhaust. Reset valves to see if that would help and still the same. backfires whenever the throtle is 'tapped' but not when you rev slowly.. still very rough... volt to the distribitor is at 12.5 and 12.8 at battery

 

[DoubleVision]

Did you check the voltage with the engine running? I had a friend with a 65 chevy pickup acting the same as yours. When the key was turned to the on position it read 12 volts. I started it and it checked out at 8 volts.
His truck would buck, kick, back fire, if you hit the throttle normally, but if you pressed it down slowly it ran okay until a certain RPM.

 

[strays]

I'll check that now cause I only checked it while not running

 

[strays]

11.57 to 12.07 while running

 

[T-bucket23]

11.57 to 12.07 while running

Should be at 14 when running. Is your alternator working ?

 

[strays]

it was checked out at Autozone and Shucks before being reinstalled.. but I have not checked it myself

 

[strays]

alt is putting out 14.8 alittle higher then idle... at cap same rpms is 10.9 ??? no glue from here!

 

[DoubleVision]

10.9 at the distributor cap just off idle? if so you found the problem. To run a experiment you could run direct to battery and see how it runs, I would only test it in the yard however, Since it can`t be shut down unless the wires removed from the battery. This can cause a safety issue if a emergency happened while driving and you had to shut it down.

 

[strays]

new wire ran to ign in fuse box.. unfuse but turns off with key.. 14.4 at cap off idle.. still backfiring and very rich.. screws on carb at 1.5 turns out.. running little smoother but not right yet.. the rich seems like a carb issue but the backfire has me stumped

 

[DoubleVision]

With most of the ignition issues out of the way then it sounds like there is a problem with the carb. The confliction with this is carb and ignitions usually give the same symptoms. The only thing I can recommend to check other than the carb is make double sure the firing order on the wires is correct.

 

[strays]

Thank you all for your help on this. I'll be working the next three days so if anyone gets any idea great... if not, looks like I'm going into the carb next week. I'll keep checking and updating! Thanks again

 

[cobalt327]

Be sure that the accelerator pump gives you a squirt as soon as the throttle linkage is moved.

Correct adjustment is important, More on adjusting the pump HERE. This article covers much of what's needed to get the carb right.

 

[lmsport]

Check your valve adjustment. What brand of lifter? Is this a GM built crate, or somebody else?

 

[sbchevfreak]

Double check the firing order - crossing 5 & 7 will do this, as well.
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