AudiOn19s

absolutely agree it's track dependant. Study the data, look at the various gear charts and determine what's best for your home track and go with it.

I don't think the cost between R&P vs. Regear is really any different these days. Pick the one that works for you.

Personally because I drive my car a good bit on the street still I'd probably go for re-gear and keep stock 6th gear ratio for highway use.

However, I'm convinced that for my home track R&P would be ultimately quicker in lap times over re-gear. I konw that's the minority impression but it's how I feel things shake out gear wise for the track I visit most.

Andy

GrantG

Don't forget about the expensive option: Do Both re-gear and R&P. This can be a good cost-no-object solution (this is what the factory race cars do).

Probably just need to change 3rd, 4th, and 5th if also doing R&P...

Good solution if someone has already done R&P, but isn't satisfied (this way, car will pull harder in every gear while reducing rev drops between gears).

GTgears

Couple comments since this has been bumped.
Erik Johnson no longer works for GBox. Don't know if they replaced him or monitor that userID now that he is gone.

You absolutely cannot compare a 997 GT3 and a 996 GT3 with respect to gearing. They are way different than each other (plus have different powerbands and redlines). The 997 is so much better geared out of the box. As long as it doesn't make the 2nd gear too short, the R/P option is arguably better if you are only doing one on a 997. Not so cut and dry on the 996.

Regards,

Matt

JarmoL

How about fitting 997 box to a 996? Shorter and closer gearing especially if used with 18" wheels. Is this possible.. does it fit in there without any modifications??

GTgears

Yes. Though there is a slight cv difference on some cars.

JarmoL

Does anyone have 997.1 gt3 gear charts available? It would be interesting to see how it'd look with 996's lower redline.

997gt3north

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)
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 -------- 43 mph --------
2nd: 2.26 -------- 73 mph -------- 5000 rpm
3rd: 1.64 -------- 100 mph -------- 6100 rpm
4th: 1.29 -------- 127 mph -------- 6600 rpm
5th: 1.06 -------- 151 mph -------- 6900 rpm
6th: 0.92 -------- 174 mph -------- 7100 rpm

the above 997 speeds would each be about 2mph lower with the shorter 335/30/18 Hoosier and about 2mph higher with the taller 325/30/19 Hoosier


Comparing top speed OE gearing 996 vs 997 with 8200rpm limiter and then 8000rpms for 5th/6th (each with OE tires - 25 vs 26.3)

Gear -- 996 ----- 997
=================
1st --- 46mph --- 49mph
2nd ---82mph --- 83mph
3rd -- 114mph -- 114mph
4th -- 147mph -- 145mph
5th -- 173mph -- 172mph (redline is 8000)
6th -- 203mph -- 198mph (redline is 8000)


- for what it is worth, my personal observation is that OE vs OE, the 997 adds about 2mph in 3rd and 4th and that allows on many tracks a gear change to be avoided redlining into 3rd and 4th gear corners - but a 997 with a 4.0 r&p adds another few mph a gear higher which makes it even better - for example that 151.3mph redline in 5th handles Mosport, WG and VIR perfectly and the 4th at 127mph versus 114 and 116 and makes it again perfect in many spots for avoid a 3rd to 4th momentary gear changed that is often necessary
- but, the above is not necessarily true if your max speeds into those corners are slightly lower - in which case the 996 is actually better as a 147 redline in 4th and is pretty near perfect for the above tracks as well
- it is actually the above that I think many early 997 drivers noticed - and that is up to about 135mph, the 996 is dead even with the 997 in accelerating out of a corner - and that is because the gearing works in many corners to the 996's advantage

- so, again it is track specific

- if you are not racing - none of this matters


- finally, i would also like to add that a 996gt3 owner can just run a taller tire like the 315/40/18 Hoosier at 27.3 height and basically up their top speed in 4th and 5th by 7mph if that is an issue (4th would be 121mph and 5th would be 156)


And finally, finally for the track rats and what they likely see on the track (996OE, 997 with 4.0, 997 RS with 3.89) - that and you notice the torque of the 3.8 engine - never mind the 4.0 engine

Gear -- 996 with 3.44 - 997 with 4.0 - 997 with 3.89
=================================
1st ------- 46mph -------- 43mph --------- 45mph
2nd ------ 82mph -------- 73mph --------- 77mph
3rd ------ 114mph ------- 100mph ------- 106mph
4th ------ 147mph ------- 127mph ------- 134mph
5th ------ 173mph ------- 151mph ------- 164mph
6th ------ 203mph ------- 174mph ------- 197mph


And if that isn't enough for everyone, instead of a 4.0 r&p for a 997, the 3.89 looks like a better choice and if there are any 997GT3/RS 4.0 car owners that want to change things just to change things and maybe beat that other 4.0 by 1/2 second, there is a well known 4.125 r&p that you can install (see data below)


Gear -- 997mk1 with 3.89 - 997RSmk2 with 4.125
=================================
1st ----------- 44mph -------- 43mph
2nd ---------- 75mph -------- 72mph
3rd ---------- 103mph ------- 100mph
4th ---------- 131mph ------- 127mph
5th ---------- 155mph ------- 154mph
6th ---------- 179mph ------- 186mph


if you had the above type 4 liter car, added a 7th gear and 40 milisecond PDK shifting - you get the upcoming 991RS - and it is going to be crazy fast