Lag has as much to do with entire setup as it has to do with turbo alone. Level of boost run will also effect lag.(We all know this) It is very hard if not pointless to compare X turbo to Y turbo if they are not both on the same car and setup. I agree with Rice that it is a nice setup. Now that TiAl has thier stainless housings it no longer has the advantage over those so called truck turbos ;) New kit to be released shortly :)

If you're deciding on a SPL or KAI, see this thread https://www.rx7club.com/showthread.p...&highlight=spl

I didn't realize this. So, if my turbo doesn't change, and all I change is the setting on the PFC to specify more or less boost, then I will expect to see more or less or less or more lag? I never noticed this and don't understand why this would happen. Am I taking this all out of context? I must be. Please explain.

For instance, if you want to run 22lbs of boost and you run a 20lb. wastegate spring, it'll spool fast as hell compared to if you were running a 10lb wastegate spring. But obviously the more boost you run, the longer it takes to get to that point.

/\ never knew that

One other thing that effects lag is timing and split timing. If your running race gas, you can be VERY aggresive with your timing which helps spool as well.

Ernie kinda hit on it. If you run a 42R at 20psi it's going to take X amount of time to get there. However if you run a 42R at 30psi. It will ramp up quicker(to a point) and certainly hit 20psi faster than if you were only running 20psi max.