I know this is a dead thread but,

It will require 4 6AL's to use the rev limiter function properly.

MSD 6 AL-2 includes a two step feature to the 6AL, and is half the size and slightly more powerful with less current draw, but again.. requires FOUR.

 

Your right this is a dead thread. I can definetly tell you after 1 broken apex seal 3 different times that the rev limit only cuts the primary injectors. While you secondaries keep firing. This allows the engine to continue to turn with enough power and definetly not enough fuel and will deonate. I have the Aux rev limiter set up on a earth button set to 6000 and -10 degrees of time taken out. I have no problem going up against the rev limiter and building bust no deonation. So to conclude I turned of the rev limit and the rev cut I set at 9000rpm and boost cut set to 15lbls. I have not had a problem.

 

Ya, the way I run mine is...

revcut at 9200 RPM's with T*RPM value at 9000 RPMs retarded 8 degree's and the RPM WOT at 9000 richend up pretty good to around 10%.
and boost cut at 16 PSI, with the 16 PSI load setting richend pretty good and the T*MAP at 16 PSI reatarded 8 degree's again.

(both the t-map and t-rpm 9,000 RPM settings are retarded 8 degree's more than they would be if I had a smooth timing flow, not as in the value is actually 8 degree's retarded.)