Hey guys I just installed a set of Gt2560r or aka GT28r turbos on my Z. It's a 90 TT 300zx 5 Speed and want to know if anyone else has similar spool up or if I'm having issues somewhere. Spools at 3000 rpm with 2 psi at 3200, but don't get full 12 psi untill 5000 rpm. Does this sound reasonable? Did boost leak test and found none, supporting breather modes are full 2 1/2 turbo back exhaust, no cats, dual selin intake, and z1 intercooler. Any feedback would be great.

 

I cant help you but good luck!!!!!!!!!!

 

Sounds like you have something wrong. I'm running the same turbos gt600r kit from z1 and mine starts building boots at 3k but i'm well over 20psi by 5k rpm.

 

When you're driving, does it feel like what the gauges say? Maybe your boost gauge is inaccurate. Is your ECU upgraded?

 

Also, what gear(s) are you testing this in? My first gear seems to be boost-limited, not sure if that's stock or what. It might even just be that it doesn't have enough load in first gear to build full boost. So ya, try it in different gears if you haven't already.

 

Boost is control by a Greddy Profec Spec 2 and my boost gauge is a Turbosmart. It's set on 12psi low boost but it'll got 16+ at 5300rpm or so if I set it that high. Yes, the ECU is upgraded for 615cc injector and dual POP. Boost come on hard so I'm pretty sure the gauge is right. I usually test it on gear 2 and 3, as first gear is pretty much useless.