Ed Newman

The stock gearing is actually very good if you look and 3-4-5. Regearing it to basically put 6 to the same ratio as 5 and them adjusting 3-4-5 to stay in proportion is a big benefit. I regeared (not R&P as no one makes on for the M96 trans) my 3-4-5-6 and the difference is quite noticable. Funamentally, a R&P will have the same exact effect but will also lower 1-2 which you may not want.

RYDLKHEL

Hey Nordschleife: Typical German arrogance. A 3.44 rear end is anything but exciting. It's a design compromise to facilitate decent fuel economy in the brochures and glossies. There's nothing wrong with modifying a Porsche. That's what makes the brand so alluring. They're not garage queens. There are many ways to improve upon them (intake, exhaust, suspension, gearing, mass reduction, etc.), and pursuing those improvements shouldn't be shunned. Congrats on bringing an interesting thread to a screeching halt.

911SLOW

Viperbob1

4.0 R&P has a much smaller pinion that the 3.44. This also leads to weakness and is prone to breaking. In a Cupcar, part of the game. On the street and doing DEs, I prefer to regear a few gears for improved performance and reliability.

911SLOW

btw before you all start debating, this is a 2007 thread, we are now in 2011.
Porsche already "re-geared" the 3.8-4.0 GT cars with a shorter RP, so let's move on.
You have a local track(s) ? study it and decide what gears work there best.
That's the beauty of these boxes. you don't have money for a proper regearing? just install a shorter RP in your GT3s.
you don't care? leave it stock.

ok?

P.J.S.

Slow
Did they re gear the 3.8 gt3?
I thought it was the same gearing and ring and pinion as the 997.1 3 and rs
3.44 etc

I thought only the 3.8 RS has a re gear in the form of a 3.89 ring and pinion and a shorter 6th...

You are all knowing - am I mistaken?

Leigh2

^ PJS great avatar of ORP...I need to get back there.
I have re-geared my 997 GT3 and my 996 GT3 changing 3, 4 & 5 and moving 5th to 6th. It makes a big difference...

P.J.S.

Totally agree - I did 8:33 ring and pinion and new first thru fourth gears and kept factory fifth and sixth

These cars are awakened with alternate gearing

NJ-GT

997.1 GT3, GT3 RS and 997.2 GT3 have all the same gear ratios and the long 3.44:1 R&P gear.

3.8RS and 4.0RS got the 3.88:1 shorter R&P (8:31), and a longer 6th gear.

P.J.S.

Ah yes, I was almost right
Once again my yoda sets me straight
:-)

BBMGT3

So any consensus on this one?

Am sure changing every gear would be beneficial overall, but is putting in a 3.8 or 4.0 R&P a cost effective compromise?

P.J.S.

Moving 5th into 6th and changing 3, 4, and 5 is about the same cost as just changing the ring and pinion and seems to be preferable to just doing a ring and pinion

That being said, many people just drop in the 4.0 ring and pinion and are pleased - this is what I did on my former 996-3 and it was very effective.

I absolutely would do one or the other - it is how the car should be geared from factory IMHO

BBMGT3

Well, currently my 997.1 tops out in 2nd at about 75-80mph, 3rd is good for 110-115mph, 4th 135mph or so and so on. What sort of difference would a 4.0 make?

P.J.S.

I will be in my office in about 3 hours - I can tell you then if no one chimes in before

I have a few gear charts and I am certain one is stock vs 4.0

If you pm me your email I can send you a gear chart in excel that you can manipulate etc.

997gt3north

Your calcs are out a little I believe
As posted by NJGT a few years ago
Even these, I somehow think I've seen 118mph in 3rd in a 997GT3.


996GT3
Stock Michelin Pilot Sport 2 295/30R18 (25.0" tall). 5th and 6th gear redline at 8,000rpm

Gear Ratio -------- Max Seed -------- RPM on upshift
=======================================
1st: 3.82 -------- 46 mph
2nd: 2.15 -------- 82 mph -------- 4600 rpm
3rd: 1.56 -------- 114 mph -------- 5900 rpm
4th: 1.21 -------- 147 mph -------- 6400 rpm
5th: 1.00 -------- 173 mph -------- 6800 rpm
6th: 0.85 -------- 203 mph -------- 6800 rpm

997 GT3
R&P: 3.44:1
Stock Michelin Pilot Sport 2 305/30R19 (26.3" tall). 5th and 6th gear redline at 8,200rpm

Gear Ratio -------- Max Seed -------- RPM on upshift
=======================================
1st: 3.82 -------- 50 mph --------
2nd: 2.26 -------- 85 mph -------- 5000 rpm
3rd: 1.64 -------- 116 mph -------- 6100 rpm
4th: 1.29 -------- 148 mph -------- 6600 rpm
5th: 1.06 -------- 176 mph -------- 6900 rpm
6th: 0.92 -------- 203 mph -------- 7100 rpm

997 GT3
R&P: 4.00:1 (GT3 Cup/RSR ring and pinion)
Hoosier R6 335/30R18 (25.6" tall). 5th and 6th gear redline at 8,200rpm

Gear Ratio -------- Max Seed -------- RPM on upshift
=======================================
1st: 3.82 -------- 42 mph --------
2nd: 2.26 -------- 71 mph -------- 5000 rpm
3rd: 1.64 -------- 98 mph -------- 6100 rpm
4th: 1.29 -------- 124 mph -------- 6600 rpm
5th: 1.06 -------- 151 mph -------- 6900 rpm
6th: 0.92 -------- 174 mph -------- 7100 rpm