Does anyone know or have experience as to the potential top speed of a TT as far as stock gearing. Have you modded guys found the limit? Is it drag or gearing that shuts you down?

 

gearing.

 

infinity...AND BEYOND!!!




or gearing...but both answers are good...

 

Gearing. You need only a couple of nice mods to get very high rpm's in 6th gear.

Many Autobahn racers with a modified TT/GT2 change a longer 6th gear. (There are still some sick straight sections available where for example 330 km/h is not enough at all! )

I wouldn't change...For more general performance actually a set of shorter gears would be appropriate!

 

So if the motor has been modified i.e. bigger turbos,better intercoolers,engine tuning will the stock gearing allow 330km/h?

 

205mph @ 7000rpm and stock tire sizes.

 

No. Unless you raise the rev limiter 326-327km/h (speedo indicated) is your max in 6th before limiter intervention. Your real speed will be 305-310km/h. However with mods you will get there much more quickly.

 

I tested it once with both D-Box & Garmin. It was 318.8 km/h according to D-Box. It showed 337 at speedmeter by factory hollow 18'. The whole set up was mainly under The Speedgallery Zero clearanne K16/24 @ 1.3 bar. You can see it's not reached the redline yet but I had to drop out for safty matter......
PS. 01 "Tip" 996TT

 

Interesting, mine climbed up to red line no problems and hit the limiter @ 326-327km/h on the speedo (I have an estimated 530bhp at crank).

 

I guess it could be the difference of transmission.
Frankly, it is too dangerous to do this, for both turbos and engine. I only did it twice to test the limitation after mod, 327 & 337km/h.
I do tset 200-300 km/h more often with 16/24s or 24/18gs, the later did climb much faster but I wouldn't test the top speed any more.

 

I've been a 178 mph (GPS verified) in stock 2002 carrera. It seems odd to me that a stock Turbo with 100 hp and 100+ lb/ft torque extra can only muster an extra 11 mph on top speed (per owners manual top speed of 189 mph). Is the factory conservative in its estimates?

 

1.2-1.3 bar with rev limiter at 7050 rpm.
341 km/h hitting the limiter on the speedo and 326 km/h with the gps !
Not bad ... !!!

 

Not really its all about;

The Aerodynamics of Drag and Power

The critical thing to understand is that drag increases at the square of speed. That is, while power increases in a linear fashion, drag increases exponentially with speed, in a parabolic function. For example (neglecting the effect of rolling resistance), if 100 horsepower would push a certain vehicle 100 miles per hour through the air, doubling the speed to 200 would require two-squared or 400 horsepower to overcome air resistance, while 300 miles per hour would require 900 horsepower.

Components of the following formulae which can be used to compute power required to achieve a certain speed in a vehicle is:

Power = 8.702 x 10**(-6) x CD x A x V**3

In simple terms, you need a lot more power for significant gains in speed at vMax once facing "the drag enemy".

 

Just curious, why would you say it's dangerous? I only stayed up there for 15 seconds (didn’t see much point holding it there for longer anyway) but temperature was fine (80 degrees) and oil pressure was right up. All seemed fine to me.

 

It isn't that dangerous for the mechanics. More dangerous for your driver's license unless there's free speeds

Yep those 3.6l Carreras are fast! I've driven myself a same car to the same speed!
(It was too 178 mph on GPS, atually it was 296 km/h in the GPS and 305 km/h in the speedo)
...we have tested the limits...almost

That car's rated considerably lower at 285 km/h by the factory. Porsche is a bit conservative in its claims, always has been. That is a known fact.

Turbo isn't massively faster due to drag. That's why many fast Autobahn Porsches are narrowbodies (Ruf and 9FF for example have very fast narrowbody models.)