Quote Originally Posted by pat mccarthy View Post
yes you can pull 52 with vac adv thats why i ask what the vac was when it pinged you do not want 52 under a mid load if your hi on vac. your pulling adv and your rpm will be pulling more mechanical adv as rpm s go up you want to be droping the timing out under a load .unhook the vac and set timing as hi as you can get to 32 or 36 see if it will start with out bucking the start off the engine if it seams ok take it for a ride and see how it runs then work with a re curve kit .i have not played with a GM dist in 20 years . use the MSD set them up all the time for blower engines hi CR race engine and street strip.air boats .offshore boats. EZ to set up they have a limt bushing to set the curve in the dist i put about 10to12 on the crank and the rest in the dist use a lite sliver and lite blue spring it all comes in at about 2800 .they are pricy but you can tune them in for just about any job
I won;t be able to check vac under load till Sunday night at the earliest so we will just have to wait on that info, but I can tell you this, it pulls 14" of vac at idle and 23" cruising above 1500 RPM, not sure about the rest under load but I will test and document as soon as I can

If I run more than 8-10 degrees of initial timing she will ping, I can start it with 20 degrees advance but it is not drivable without sounding like downtown compton on a saturday night - boom pop boom boom pop

I want to keep this car parts-store friendly, no gucci parts on this one, this is my driver/dirt bike hauler and if I break down in podunk, AZ I need to be able to buy parts at any local store, no time to wait for summit or jegs to ship fancy stuff - but I know MSD exists for a reason

So far after playing around with my current HEI and springs I can tell you that ligher springs only allow full mech adv to come in sooner, it doesn't go higher. The most timing I can get w/o vac advance is 22 to 24 degrees, I will have to blueprint my dizzy, I am sure something is hanging up in there...

Will the MSD weight/spring kit work/fit in a standard HEI distributor? Otherwise I was going to order the Mr. Gasket version that *guarantees* full power at 2000-2800 RPM