Converting Distributor to Vacuum Advance?
Racer
Joined: Nov 2008
Posts: 321
Likes: 2
From: Auburndale FL
85 & 86 are larger cap distributors, in 87 they switched to the small cap. Not sure if you could clock the dist body with enough room for HEI vac advance can. I'd have too look at my car and see what's all around it, but you can buy a msd small cap vac dist if room was the problem. 87 up at least can use this for their msd box http://www.summitracing.com/parts/msd-8876/applications
Uh 87 what??? My 87 has the large HEI not the small, and it was factory until I replaced with a new/rebuilt factory one anyway.
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 113
From: Michigan
edit: Just read all C4 had the large cap, if so that's interesting.
Last edited by BOOT77; Mar 12, 2014 at 02:54 PM.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
timing tables are pretty much the easiest part of tuning. Set the timing for 22 degrees at idle. Have it come all in at full throttle, 33 degrees at 3000 rpm is a good place to start. at part throttle (cruise conditions), you can dial in up to 45 degrees. There, you're all done!
Safety Car
Joined: Sep 2001
Posts: 4,157
Likes: 554
From: Glenbeulah Wi
Copy a traditional SBC advance curve and dump that into the timing table and it will work fine. It will act just like the mechanical advance distributer with vacuum canister that you are trying to create.
