I'd like increase top speed on my Rs tuning 542 Hp Kit that has 7000 rpm rev limiter .
Do you know some company that sell a longer 6th gear ratio for 996 TT and how much does it cost ?
I' m thinking to do this job when i must replace the clutch to limit labor cost.

 

Wouldn't be easier to have the limiter removed from the ecu ?

 

Yes,a longer sixth gear is available.i just had all my gears changed by Brian Copan and with the longer sixth and a 7800rpm redline the geared top speed is 263 mph.I believed it was sourced from Guard Transmissions..

 

Really you would want a taller 6th, why?

I already think 6th is over tall as a hiway gear; it leaves my car in a running rough RPM at hiway speed.

 

F'in insane....

 

Rob Kenworthy had a 2004 GT2 that he put a taller 6th gear in as well as a small power boost from the motor. He ran the car at 186MPH all day in the Gumball Rally for a few years. I'd say that car is more than enough motivation/proof for this.

 

HI,Did they also change the 1 and 2 gear ratio to make it a close ratio,less RPM drop between shifts?? Thanks

 

Yes John every gear was changed from 1 to 6 and made longer.1ST goes past 60 mph.They were also done straight cut.Brian did such a nice job setting them up the gear noise isnt bad ,in fact i think it sounds good.Before with the stock gearing and extra power 1st and 2nd were basically useless.

 

What situation are you in that you're running out of gearing at top speed? What's the mechanical limit of the stock 6th gear? I've only had my Turbo up to 180 or so and still had plenty of gear to go.

 

That trans sounds like the hot set-up..Straight cuts are the way to go for efficency and load.I run 1'' bigger diameter tires for getting a little longer gearing.
If I may ask,what was the cost of just the complete trans? Thanks

 

just took my kids for a ride 15 min ago. 125 in 4th was all i needed . drive the car about once a month and seldom even use 6th gear, if it were taller think i,d be luggin

 

Interesting thread! I was just driving my Turbo around town stop and go doing errands and thinking about how I dislike the trans gearing. It's comfortably good to about 15 or 20mph in first, a bit more in 2nd, and comfortable at 30-35mph in 3rd. Yes, I know you can wind it out in first and 2nd but it's annoying to constantly being shifting a 400+ horsepower car with a top speed of just under 200mph. My GSX-R 600 will do about 85mph in first gear and my sons R1, 100mph. You can still ride them around town in 3rd, 4th, or 5th without going over 40mph. My '99 C2 Cab was geared much better IMHO.

 

959 has a taller 6th its a swap for 6th in the 996tt box. I am sure there out there GL.

 

Bikes rev to 14k plus not the same as a car that revs to 7k

 

Glad to hear that you are happy with your new gearbox. You are correct that Brian worked with us on it. The 6th gear that you are using was originally designed at the request of Mosler for use in the MT900 when they were looking to make the world's highest top speed production vehicle (a record the Veyron holds these days I believe).

We also make a 6th gear that's a step off the one you used that's more appropriate for someone who isn't going to regear the whole box and just wants a 6th gear with more legs to run...