[NikWilson]

With 2nd generation GT-SS turbo's and standard internals, what is the max' boost pressure (in bar) that can be safely run?

I am only running 1.15 bar with my set up, but am sure I can take this a little higher. I think that 1.3 bar is the answer, but just wanted views on this.

680 cc injectors
Nismo AFM's
Tomei pon cams type A

Nik

 

[Nocturnal]

I think the turbo will happily run 1.5bar in the midrange for a little extra torque and taper off to about 1.4bar at the end for max power.

The long as the mapping is up to date, I am not too worry about the internal. Some people say the head gasket need changing over 1.2bar, but even standard nissan item are metal so I am not too sure what is the big fuss. Again, it is det that kill head gasket/piston/engine.

 

[NikWilson]

Thats interesting. I have fitted a HKS 1.2mm steel head gasket as well, so I guess it coould be run to say 1.4 bar or even 1.5 bar.

Not that I intend to do this, as at 1.3 bar, there is enough power and torque for me! But I just wanted to get a few views on this, since I am not sure of the definative answer!


Nik

 

[Nocturnal]

From what I have read, the GT-SS are too small to hold boost up on the top of the rev range.

Therefore you can get 1.5 bar in the middle to get more torque, but the boost will naturally drop off to about 1.4bar as it is not efficent enough due to its size.

You can go for more in the middle say 1.4 bar and taper off to 1.3bar if you want less stress. But I don't think most of us drive the GTR enough miles to worry about stress as it seems.