itstock

I have a garret T3 .42 compressor .48 turbine on my d15b7. I have a 2.5" downpipe back exhaust,but i dont hit full boost (8psi) till around 4k rpms. now with this turbo id think it should spool up a little faster. Also, it doesnt really seem to make anymore power after ~5500 rpms,would it be worth switching to a .63 turbine housing for the extra top end power, or would i see much of a difference?

stargazer

Something is wrong if it's losing efficiency at 5500. I don't know about the spool up time..sounds kinda late. You might have a boost leak or something is messed up with the wastegate.