Join Date: Mar 2002
Location: Austin, TX, USA
I just fired mine up for the first time after updating the ignition and carb to fix the same problem you are having.
When I bought the car, the previous owner had a distributor in it with no vacauum advance and no mechanical advance. So I changed out the distributor with a dave's small body hei unit. I also now have a vacuum advance with adjustable diaphram preload and a stoke limiter.
The carb was an old holley 750 (too big) and hadn't been rebuilt since jesus was a baby. Also, it had been fooled around with trying to overcome the loaded idle problem. Both power valves were blown and the jets were too fat. I rebuilt an old holley 650cfm carb. I found the main body was warped some so I paid a machinist $20 per side to flatten it out. A soak, new kit, and factory spec jets have me running a lot better. I also installed those power valve protector check balls to reduce the blown power valve problem.
All this made a huge difference in overall performance. But I still have a bit of a problem. I am certain now that the cam is just too limp at low RPMs and my stock stall speed converter needs to be replaced with about a 2400 stall unit. The other option I am considering is stepping back to a different cam for about the same money.
Anyway, start with carb and ignition and make sure they are sound and properly setup. Tell us about your cam and some of our cam-guys here can let us know if your stall speed needs an increase.
68 Coupe, 350 w/ Edelbrock Performer RPM heads, cam, intake, 700R4, Dave's small body HEI