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A mate has a r32 GTS4 rb25/30 that runs 4.375:1 diff gears.

That used to feel rediciously short. He recently dropped a set of 245 45 18's on to it and it has made it more pleasant to drive.

He still believes first and second are too short but what do you expect with a high powered car.

The more power they make the quicker they are going to buzz through the gears. :)

Myself driving the GTS4 with its larger dia tyres makes it feel pretty well balanced. The 4.375:1 behind the gts4 rb30 was horrid. Now with the tyre size he's running its down to around 4.11's and it feels just nice.

When I say just nice, it feels just nice with how and where the turbo spools vs road speed (general street corner entry/exit speed etc.)

Its a GT35r .82 that pulls really strong from mid 3000's so general street driving its easy to enjoy the setup without having to ring its neck.

3.5 and 3.7's I really think are simply too long. Chances are with a decent turbo setup your road speeds are going to be too high to be able to enjoy the car at every corner.

As Gary has said... Try not to compare a view on diff ratio's in a 33/32 gtst to a gtr as the gtr weighs a couple hundred kg's more.

My mates GTS4 feels noticably flat compared to my lighter gtst. My comparison with the GTS4 isn't the best as mine runs a higher static comp and has headwork which improves low/mid response but none the less its the best I have.

Look at where and how your turbo's are going to spool and then look at your general driving style.

If its a street driven car its silly to think you will be hard under brakes in to corner after corner with rev's up at 5000rpm as the majority of the time you will be doing legal road speeds and simply want to leave a corner at a brisk pace without making yourself look like too much of a 'hoon' yet still enjoying yourself.

Hope that all made sense. :)

yes.

im concidering going to a 4.375 diff ratio in mine.

mainly fot the track.

the gearset in mine is a littlke odd. some unknown jap set.

at 8000rpm heres the speeds i get.

1st. 90kmh

2nd 140km/h

3rd 195km/h

and taking off in 1st is shithouse with my nismo tripple. and with a t04z its lag city.

but once you get rolling its all on and staight to jail lol

any advances on whether it's possible to change the front diff in the GTR without pulling the engine?

not a problem...we put a cusco 1.5 mech in the front of our racecar Scoob, 4 hrs but i reckon we'd do it quicker now we know how to do it.

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