You could try this experiment. Twist the distributor to advance the timing another 10* initial. You'll have to back off the idle screw due to rise in idle speed. Now once you got the idle @ 800 again warmed up put it into gear. Does it die or not?

 

calwldlife, Ported vacuum . The Corvette is all original with the exception of the motor work that was done to it. Still trying to find out what motor work was done.Steve

 

REELAV8R, Like you said before 3 to 4 is low. Spec. for an original 350/300hp. I agree with you. We will kick it up. Steve

 

Yes, sorry not trying to repeat myself, just trying to isolate the problem.

 

REELAV8R, No smell, fumes. or smoke. Dark grey tail pipes....Tomorrow we are going to start down the list of items. Starting with the basic. The items we have talk about will all be done. Steve

 

REElAV8R, No worries about repeating yourself. My two Corvette buddy's that are also working this problem here are doing the same thing..It’s a good thing. Steve

 

spec is 4 deg at 700rpm neutral, 600 rpm gear

ported vac, so check
carb condition,
slipped balancer,
stretched timing chain,
fouled plugs or gap heat range

a clean 350 should run just fine at 4 deg in gear.

now performance tune is helpful for idle but
The car should run at factory specs.

 

calwldlife, I agree 100% The Corvette should run in spec. One of the items on the list is Engine Diagnostic Tests. ie fuel pressure, compression, vacuum checks again, filters, plugs...etc. your list too....You name it we are going to look at it...

 

it is a head scratcher.
I have had them run with weak spark, dirty carbs, and general worn out things.

Pull a wire at the cap and loosely place it it its spot so you can see the "hotness" of the spark.
blue baby, no yellow needed.

see if spark plugs are wet from too much fuel.

You plan is a good one. I am lazy and want to get an idea of what is going on before I test to confirm it.

good luck

 

calwldlife, You are so right to say it is a head scratcher, although I was thinking about anther part of my body when I read that, Anyway you can see it’s getting late and we are tired, so when we get finished with this problem and we will in the next couple of days, we will let everyone know what we found. Right now we are in the process of engaging all the variables and thoughts you guys have brought to the table, they are all good and we thank you.... good night everyone.... Steve

 

calwidlife and everyone, We found the problem..But first this is what we did. Went through our list. No 1: Bad fuel, Siphoned and cleaned out the tank, fuel lines, changed fuel filter, pressured tested the system {5.5}, new 91 octane ethanol free, 3 turns on the air and fuel mixture when we did our adjustments, measured vacuum at 20, choke and fast idlest 1100 good. 2.Vacuum leak at the windshield wiper door. Vacuum switch was replaced by a Wilcox one. 3. Tune up: plugs, wires, cap good, coil check out at 40k, has a Breaker Less ignition system "good choice". 4 This is the big one: Rockers arms loose due to adjustment bolts. Replaced all rocker arm bolts and relashed the valves. Some of the original bolts you could almost turn by hand. We figured they were used for the motor rebuild or they were Chinese made or both. The owners found part of the Motor Build Sheet, not complete though. Timing, carb, vacuum, vacuum at the transmission modulator and torque converter specs we present. We were going to take the timing cover off to see if there was any information on the end of the camshaft but we didn’t. We had enough information on the build sheet. Initial timing set up at 7 degrees. Put some Sea Foam in the tank. Verified some carb and timing adjustments and No More Stalling....Steve

 

Nice work….now dial another 7 or 8 degrees of timing in it and make sure the vacuum advance is drawing from full manifold vacuum….

Jebby

 

Nice
loose rockers could act like stretched timing chain.
certainly throw off the "power/torque"

hope you have a good running keeper