I'd suggest sending off the exhaust housing and having it Ceramic Coated, then use a turbo wrap kit to insulate it further. This likly to yeild around 600RPM faster spool, maybe even more. The other things to do is have a a shop that specializes in tuning custom equal length turbo manifolds. When tuning the runners they have to scavenge the exhuast gases and make them work together. The main idea of the sign wave theroy is to get the first exhaust pulse down the runner and use it to create a basic vacuum to PULL the next exhaust pulse DOWN it's runner. If you don't then they work against each other drastically slowing down the exhaust pulses velocity, which in turns KILLS your spooling time! The other thing you can do is Ceramic Coat your manifolds, down pipe, exhaust pipes and the thermal wrap them on top of that. All those steps together will DRAMATICALLY increase the exhaust energy & velocity while further minimizing back pressure which REALLY helps it spool MUCH faster. Some other things you can do is port out the internal waste gate, turbo inlet and manifolds. The porting process has been know to help stock turbo setups spool 400-600RPM's faster. Extrude Honing is also a good technique, not only does it help spooling but it also adds a significant HP gain. It has been reported Lisa Kubo's turbo had the exhaust side Extrude Honed and gained 50HP across the ENTIRE power band!!! Well you guys keep digging and you'll find even more tricks!<p>P.S.
I'm using a .78A/R Exhaust Housing on a 1.6L B6T. The turbo is supposed to start rocking around 3200RPM. You KNOW I've got it tricked out some to do that!!!!
