I have a '72 Chevelle with a fairly new and mild 350 in it. I have a fairly bad miss when idling in gear with the brake on. Otherwise it does run and drive OK. Back in May when I installed the new/used engine it ran fine with my old points dist. I then upgraded to a new HEI dist, new wires and plugs. I had a slight miss that at least did improve some when I bought a different(more expensive = better?) set of plug wires. Now that miss is getting worse so I want to replace the dist cap thinking maybe I got a cheap cap with the dist.

Being there was no HEI option for a 350 in '72 what vehicle do I buy a cap for? I know I can look in the books to find the first year for HEI and get that but what has everyone around gere been doing?

Any help appreciated ... Thank you!

Just stroll into the store and ask them for a GM HEI dist cap, if they wonder or look stumped tell them for a non-computer controlled vehicle.

Accell makes some pretty good caps and HV coils. I ran one for years on my stocker HEI and it worked mint.

GM hei caps from 74 to 83 are the same,they may go later years but I don't know.

Also, be SURE you have a solid +12V to the dist. DO NOT use the 'old' cotton covered yellow wire for a source.

Get one from your local NAPA store, they have brass inserts and get their rotor too.

Good note on the full +12 volts, I do have that. I did find a cap and coil in the garage so I cleaned the cap up a bit and put all that in ... still missing. I put all my old points stuff back in, dist, cap/rotor and plug wires ... still missing (which it wasn't back in May).

I hooked up a vacuum gauge and it fluctuated between 15 and 17. Based on the little manual that came with it I need to adjust the carb (quadrajet). The 2 idle screws in the front of the carb were turned out (counter-clockwise) only about a half turn so I went to a full turn and it seems better. It did seem to run better on the way to work this morning but then it died on me. Felt electrical so I messed with the wires and she fired so I could get to work. I will put the new HEI and wires back in tonight.

The carb has been working good all summer but I suppose they could get dirty or out of adjustment. Any ideas on all this?