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Recommended Boost

HI i am new into the whole small liter turbo cars.  I recently bought a 1992 R32 GTR and I am currently running at the stock .5kg boost. I recently met some random guy at a show and he was telling me not to go over that and how he blew his up doing a brakestand.  (I was bouncing off the rev limiter at 1.09kg doing a breakstand just before).  Just to be safe I thought id ask what your opinions are. What boost should i run at?

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The car is currently tuned and has 427 all-wheel horsepower. Features include air conditioning, power windows and power steering. The rear wheel steering has been removed. It has an upgraded front bumper with the Nismo N1 air ducts to help cool the intercooler, and it's been upgraded to R34 Nismo N1 turbos. It's also equipped with rare Nismo oil separator, Apexi power FC standalone ECU and DBA and slotted rotors with Endless brake pads. Interior features include racing steering wheel, Tomei shift knob, Recaro racing seats with RJS 4-point racing harness. It has Innovative Wideband, Tomei locking rear differential, Skyline GT-R front strut tower bar, rare Cusco 4-point rear strut tower bar and Cusco rear stabilizer bar. All rear bushings have been upgraded to polyurethane bushings. It's also equipped with Apexi air-intake kit, GReddy oil cooler, oil filter relocation kit, Mishimoto aluminum radiator, HKS hard-pipe kit and Fujitsubo equal-length downpipes with a full Tomei Expreme Titanium exhaust. It rides on Volk Racing TE37 wheels 

Stock boost is 0.7bar for your car, slightly above what you've quoted. The most you should be running on your stock setup is 1bar or around 14psi, which is pretty much what you're topping out at now. 

In reality, no one can answer what your recommended boost is as each car is different. How well maintained is it? Do you flog it every chance you get? How many kms? There are so many variables. 

Play it safe, go 0.7 bar or around 10psi. Or go hard and play with fire by going to 1bar. It's really up to you. I would get go past that though. 

 

EDIT: I replied before your second post came up...

Edited by inmaniac

It is very clean but alot of smoke on the decel. 165000kms on the clock and the rear crabbs everytime i take a turn at low speed. I have to take out the rear and see if its a spool or the rear is just messed up.  I just set the boost to .7 and the base duty to 32 (honestly idk what base duty is).  Thanks for the help guys.

N1 turbos will run around 20 psi safely. If your car has 427 whp , then the turbos will be running at around that boost level. Dont believe everything random guys at shows tell you. If your car had stock turbos 14 psi would have been the safe limit. As above what is a brakestand? lol

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