Hey folks, I have a question about your timing curves for BBC's. I have a programable ignition & need to program in a timing curve into it. I was wondering what your timing curves look like. for example you have say 12* @ 500 & a total of 36* @ 4000 (or whatever) & its pretty straight all the way up through the range.

I looked @ a few of them in the MSD instructions that came with the distributor (billet, no Mech no vac adv) & they vary quite a bit over the 6 or 8 different variations of springs that you can pick, if your using the Mech adv).

I was pretty surprised how late it seems that the big blocks bring all the timing in (4000 - 5000), but from what I can tell they are all pretty much that way.

Any suggestions?

thanks
Bob

17* initial 20* in the distributor all in by 2500 rpm.

Right on Robert, thanks. do you have any idea, where the mech adv starts to come in? if you check out MSD's site, it has a rather shallow slope on the curve until the R's start to come up a bit & then it gets rather steep http://www.msdignition.com/pdf/85551_85561_8547_dists.pdf

it looks like from 900 to 1300 is where it starts to get real steep. No worries either way.

thanks again
Bob

Im a bit surprised that no one else posted here. does anyone else have a programable ignition in thier cars?

Bob

67 SS 454, MSD6A, 16 inital, 36 total, all in 2800, runs like a raped ape.

I don't have a dial back light, I try to get it to start coming in just above fast idle. I am running a Mallory Unilite distributor with no vacuum advance.

I have a Mallory Comp 9000. 15* initial and 20 mech. All in at about 2800. I don't know anyone with a big block bringing in their full advance past 3000 on purpose.