hei vacuum advance stop plate

[Kheughens]

My experience with the HEI distributor (ACCEL 59130 with coil) is you must use the vacuum advance stop plate. Initially, I did not install the stop plate and the first time I hit the throttle, the results were not good. Vacuum advanced with no limit and did not come back down. I ended up trying a few settings but found for my vehicle, the “c” option 8-11 degrees worked best (1973 350 stock Chevy). Your configuration may be different. BTW, best decision to move away from the original points based distributor!

 

[Ricko1966]

Thank you Ricko1966 and mikeb. Good info.Have printed this for checking my timing on the 77

If you want to find MBT which I talked about in post 10. Set your total to 30* ,vac advance disconnected and plugged. Find two land marks you can accelerate from a dead stop to 1/2 or more through 2nd gear. Run it a couple of times,check your speed at the 2nd mark. Speed not time. Bump timing 2* at a time, checking speed each time. When speed drops go back to the minimum timing that gave you best speed. If you want to dial things in even further let me know. I'll walk you through the next steps,to get curve. Vacuum advance degrees and rate.

 

[Turbo4whl]

Your configuration may be different. BTW, best decision to move away from the original points based distributor!

Kirk welcome to the forum. Your 1973 and some 1974 square body trucks are the only one's that had point distributors. All newer SB light duty trucks have a GM HEI.