I hear they change the 997.1 cup cars gear wheels (not the total transmission) with 4.0 ones as they are shorter/better?

Know anything about this?
What are the difference, is it a worthy mod for a no daily driver.

Got my GT2 seats installed and out goes the Euro Buckets, pix coming soon..

 

Motoharu - R u interested in selling the 1 piece carbon clubsport seats?

 

Cup Car gears are sequential. They aren't used in any street car. Not even close to compatible with the street box.

Is your question whether or not the ratios between a 997.1 GT3 and a 4.0 GT3 are different?

 

@GTgears: I think that's what i mean.
I hear the gear ratios are shorter in 4.0 and you can swap parts with 3.6 without changing the transmission completely.
I think two parts are needed; One tube like part, a small gear attached to one end and one large gear.
There must be a name for it other than short shift gear linkage, but i do not know.

Is it clearer now?

 

I suspect you are talking about the ring and pinion and the final drive ratio. The 4.0 got the 3.89 final drive. The other cars run a 3.44. That's the biggest single difference between the two gearboxes.

The 6th gear ratio was tweaked a little bit because of the shorter r/p and made taller, but otherwise the lower gears are identical.

 

Exactly, ring and pinion
So there is not much of a difference and not worth to dismantle the transmission?

Thank you for the info..

 

I'd suggest R&P upgrade along with an LSD rebuild from Guard while you're at it

 

Hmmm, i guess what i want to learn is, not the gt3 rs 4.0s ring and pinion but the 4.0 ratio r&p instead of 3.44 standard cars use..

Is it a good modification, are there downsides (LSD rebuild?), what do you guys recommend?
Should one get into that or leave it alone as it might bring more trouble in the long run?

@gtgears, there is a 1yo thread where you mention a new r&p, 4.12ish, is that product still being developped, updated, tested?

Where should one can order such units in NY or online and delivered to NY?

 

Hello Motaharu,

Since our parts are far from DIY components, they are not generally available for "mail order". New York is a big state. Narrow it down a little bit and I'll steer you towards one of our dealers who is able to do a proper ring and pinion installation.

The 4.125 ring and pinion has been on the market for at least a year. We also are now making 4.00 ring and pinions for racers who have to follow homologation rules. If it's for a street car/track toy I personally would be putting in the 4.125 version.

 

Hi Matt,
Thanks for the reply, i've send you a pm..

 

Aren't straight cut gears very noisy?

 

Yes they are, but I don't see anywhere in this thread where we're discussing doing that.