D16Y8 turbo overboost
Posted:
Fri Nov 02, 2012 11:43 amby Volkas
Hey guys. I'm have d16y8 engine with garrett t3 turbo programed on 0.5 bar and somtimes when i'am downshifting it overboosting to ~0.7 bar. Where can be problem?
Sorry for my bad english
Posted:
Fri Nov 02, 2012 1:15 pmby teal_dx
When you're downshifting, the engine revs up a bit. Higher rev creates more exhaust which spins the turbine faster, creating more boost. Without seeing your exact method of downshifting (how fast, rev matching, etc.) it is hard to say. But I would start by looking at the components of the system that help regulate the psi. Examine the wastegate first. Also because when downshifting, the throttle plate is opening/closing fast, look closely at the blow off valve. It may not be opening enough, keeping some psi in the system. (although that usually results in compressor surge) It can't hurt to take a look since we don't have any more details of your setup or driving style.