Tricked-Out-Toy

Ok heres the details on the car, its thirdgen with an 97 LT1 swap, hot cam, longtubes, LT4 knock module with a converted OBD1 PCM. We are using a mallory 685 box and had it set at 5 degrees retard for the 100 shot and saw 7 degrees of knock retard right away but no pinging or studdering or audible knock. so we upped the timing retard to 10 degrees and it was still pulling 7 degrees at about 3400rpms and dropped to about 5 degrees through the rest of the RPMs. This doesnt make any sense. we know for a fact that the mallory box is working properly since you can arm the system without nitrous and it is a dog N/A.

Also note that we have 0 knock retard while off the spray at WOT... Im really confused. there is no reason that it needs 10 degrees of retard out of the box! Im thinking about just pulling the max knock retard from 7 degrees to about 1 or 2 degrees...

MikeGyver

Hmm. I'd verify the AFR with a wideband to help determine if it's real knock or not.

Just FYI, I've never heard audible knock in the >200 tunes I've loaded on several LT1's.