Hey guys, 13B 4 port here, turbo. I have two MSD 6a boxes and just picked up a BTM unit for one of them. I kow I have to retard the timing under boost to prevent detonation. Money is short so I could only afford the one BTM, which timing is the more important to retard for now, Leading or Trailing?

 

umm.. first of all "one" MSD box doesn't work on the trailing... so you either have one box (leading only) or 3 (1 leading 2 trailing) (unless you are running some werid disputor setup.. instead of stock.

why do you need to retard it? what are your other mods? unless you are trying to run crazy boost / power on the stock ECU I see no reason to do it. you just need enough fuel to match the boost.

list all your mods and we can help you better.

 

Sorry Scott, I have a TO4 turbo, Webber 48mm sidedraft carb, 12a dual coil setup, the cars an 85. Its a carbed 4 port. Thanx.