Re: MSD 6530 boost retard question
Based on the 2 graphs you posted (as best I can see them with my old eyes, lol)you would install the locked distributor at 36* to achieve the "max timing" you label at 3,000 RPM in the run curve. So, out on the road if you are at 3,000 RPM and above with only part throttle so you have high vacuum you will be at 36*.
However, if you go wot at 3,000 RPM, vacuum will go to 0 (which is 14-14.5 on the boost axis depending where you live) your boost curve will pull 10* and you will be running at 26* total. Is that what you are wanting?
If you want your cruise timing to be higher, you will have to stab the distributor in at more than 36*. Say 42* if that is what you wanted for cruise. That would give you 32* at WOT above 3,000 RPM. Now for starting you would be pulling even more timing to go easy on the starter which means even higher chance of cross fire and kick back. At that point I'd recommend an ignition cutout switch so you can get the engine spinning over with no spark then flip the switch to light the fire. That is what I did when I had the 6530 in mine.
400 SBC, 9:1, AFR 195s, TH400, Coan converter, 3.50
ProCharger D1SC, Super Sniper EFI conversion 2019
1.30 60', 5.95[email protected]
on pump gas