GTgears

Where would 2nd gear top out. Poll attached, discussion encouraged.

Da Hapa

I don't think the poll got attached

FrstPorsche

65

GrantG

65 works for me too (gives 8.33 mph/1k rpm) - means peak torque at 37.5 mph (4,500 rpm). Wouldn't want it any lower and max of 70 mph, please.

ChrisF

65-70. In my perfect world, the gearing would be similar to a .2 RS.

IMOA

For me I wouldn't want shorter than 70mph. It's a torquey light car so it needs to be usable and you don't want to leave too much space for 3-5

jphughan

70. That's where my E92 M3 tops out (so yes I may be biased), but even that can already be a bit temperamental in slow corner exits or even on the street in terms of putting power down without overwhelming the rear tires, so I imagine that with the GT4 already starting with a superior power to weight ratio, it will be even more difficult, and shortening 2nd gear to top out even lower could make it too difficult to be worthwhile. Then again, the GT4 has bigger, stickier tires which I imagine would offset this issue somewhat.

GrantG

That is critical of course. Gearing is a compromise that must consider all of the ratios. Matt's question was specifically about the perfect 2nd gear and so I think somewhere in the mid-high 60's would be perfect for road and track. Thinking about the whole gear package in context is certainly the next step after this question about 2nd...

GrantG

Don't forget rear weight bias which helps a bunch too...

Da Hapa

This.

Accel Junky

For the street, I would vote 60 assuming a lower 3rd as well. I prefer to bang gears often on the street. For the track I think that would be detrimental.

Petevb

68, assuming you're moving the rest of the gear stack around it.

Much lower will slow straight-line acceleration, ie 1/4 mile, because you'll be shifting too much (for a car this quick). It would also mean an extra shift into 3rd on the average autocross course I run (SCCA will be a bit faster, but with a gear swap I don't think you'll class well there anyway).

Taller than 70 wouldn't be enough of a change vs the already available base Boxster 2nd gear (76 mph) to make it worthwhile. 68 would be ~18% increase in torque to the ground across 2nd gear either coming off hairpins or in the autocross speed range, the equivalent of adding 70 hp. It'd instantly make the car roughly competitive with GT3s off the slow stuff (where it can get the power down). It'd also let you use an extra gear on the average back-road.

The Spyder guys will want one too, same gearbox.
BMW tunes their cars to be tail-happy and slide around. Porsche tunes to get power down, plus they put more weight over the drive wheels, the combination of which makes them far less tail-happy with similar power to weight. It's a bit of a shame, as I like an adjustable car...

Jenner

67

DeerHunter

I like what I'm reading here. Without breaking out some gear charts, what Pete outlined makes sense. More torque to the wheels in 2nd and 3rd is just what the doctor ordered.

vantage

Agree with Pete. Combination of mid-engine layout plus 295 section width Cups will make putting power down a fairly easy proposition in the GT4. I've driven an E92 at the track and you do have to show some patience.