I am running a td07 with hks manifold and hks wastegate. We brought the car to a dyno shop to do some tuning.

Its boosted (8-9psi) fine up to 6k, but starting to fell above that. (5psi) by 7500rpm to be exact.

My tuner told me that it is cause from wastegate failure.

Just seeing if any has any comment on this. Also is it a good idea to heat wrap your exhaust manifold???

thanks..in advance..