Using vacuum advance as boost retard?

[jdub]

Hey folks, I'm trying to work out all the details of doing a blow-thru conversion on my motor, a '77 odd-fire. Unfortunately, due to the odd(ness), most aftermarket ignition stuff doesn't work. I think I could get the odd-fire specific MDS 6A and timing retard, but I have seen someone mention before using a vacuum advance canister configured somehow to pull timing back out instead of advancing it, for turbo use. Anybody ever hear anything about this?

 

[b4black]

Hugh MacInnes mentions this in his Turbochargers book. I think this was used on Corvairs. I will look it up when I get home. (Remind me if I forget )

Do you need the MSD 6? If not, then I believe the "Universal" BTM will work for the odd-fire and would be much cheaper.