Hey all, my problem is as follows:
Car setup:
1997 180SX
SR20DET
78,000 km's
GT2860RS
Greddy FMIC kit
Greddy Profec B Spec II
Tomei Poncams
Z32 AFM
Nismo 740cc Injectors
3-inch turbo-back exhaust
Catco Cat
Walbro in-tank flowing fine
Nistune Daughterboard ecu
Apexi pod filter
Stock S13 BOV
Car has been tuned by Yavuz at Unigroup Engineering to 201rwkw. See below dyno sheet.
The problem is that the boost is dropping off from 19psi to 14psi resulting in the somewhat disappointing power figure given the setup.
Yavuz mentioned to me when I first picked up the car that it's an actuator problem and that I should look at getting an adjustable actuator. GCG Turbo's have confirmed that the actuator that comes with the GT2860RS is already adjustable with a base pressure of 14.7psi and capable of around 22psi.
Yavuz now says that the boost drop off problem is attributable to the turbo itself and not being able to keep up with the engine as it breathes throughout the whole rev range.
I know that the stock S13 BOV will most likely be leaking in this setup but Yavuz doesn't think that it will make a huge difference when it's replaced with a stronger one.
He also went through the entire system when he was tuning the car and is happy with minimal boost leakage throughout it.
Can anyone confirm that getting a different adjustable actuator will rectify this boost drop-off issue or not, or any other possible solutions? I'd like to see at least 210rwkw with this system given the higher-flowing injectors and Poncams.
Thanks in advance guys.