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Hey SAU =)

Just a quick question. I'm kinda retarded with knowing gear ratios and was just wondering what the difference in these two sets will be with the SAME diff ratio, as in what would it do to my car / driving...?

Not sure if the Skyline R33 ratios are exact, it's the closes i could find on forums.

>>Note: The engine is an RB30/25 with a Garrett T04Z and Tomei 270 cams<<

SKYLINE OTHER

1st - 3.32 1 st - 2.66

2nd - 1.90 2nd - 1.78

3rd - 1.30 3rd - 1.30

4th - 1.00 4th - 1.00

5th - 0.75 5th - 0.74

Diff - 4.11 Diff - 4.11

Cheers in advance for any help =)

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1st is much taller in the OTHER gearset. That will mean more clutch slipping and possibly more time spent below boost making revs before it comes on boost. The problem with saying that is that the ratio is higher, so you wil be loading the engine a lot harder than with the SKYLINE gearset, so the boost threshold will be at lower revs. My guesstimate on that is that it would take slightly longer time in total to come on boost, although it will do so at lower revs, and then it will run through to a much higher speed before needing to change to 2nd and it will probably make a little more boost (assuming your boost is not being clamped is 1st by a boost controller with both gearsets - it's often hard to get full boost in 1st), and it will run through to redline slower than the Skyline gearset will. It will quite possibly get better traction with the OTHER gearset in 1st.

Every other gear is essentially the same ratio, so you wouldn't notice any change.

1st is much taller in the OTHER gearset. That will mean more clutch slipping and possibly more time spent below boost making revs before it comes on boost. The problem with saying that is that the ratio is higher, so you wil be loading the engine a lot harder than with the SKYLINE gearset, so the boost threshold will be at lower revs. My guesstimate on that is that it would take slightly longer time in total to come on boost, although it will do so at lower revs, and then it will run through to a much higher speed before needing to change to 2nd and it will probably make a little more boost (assuming your boost is not being clamped is 1st by a boost controller with both gearsets - it's often hard to get full boost in 1st), and it will run through to redline slower than the Skyline gearset will. It will quite possibly get better traction with the OTHER gearset in 1st.

Every other gear is essentially the same ratio, so you wouldn't notice any change.

Ok I think I get that =)

I plan to have it as a weekend car, so how do you think It'd go with the OTHER gearset for every day driving and when I'd like to put my foot down now and then? even a guess would be great =)

When not starting from a standstill, you'd not really know that you weren't driving the Skyline box. You don't often drop down to 1st when driving around. Although with this box you might be tempted to use first on really slow corners, which would actually improve things.

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