333pg333

I really don't think the ratios of the 6 speed are an issue. All this talk about too much shifting shouldn't really be a concern in my experience. Same with the 5 speed/S2 r&p combo. We're certainly not shifting like some short ratio n/a rally car when we're on the track. (See Youtube links below for incar footage)

odurandina

yes. for any 3.0 Turbo engine, that T-box's ratios and rear diff is perfect.

the next best thing would is a 968 box with the taller 01E euro diesel 3-4-5-6 gears that are available, and will fit.

but those sweet gears are ~$3 k.

George D

Sid,

You have some of the cleanest posts. I love my six speed, but I'm weird, but maybe having a 968TS box makes it even.

G

seattle951

Out of curiosity, what would it cost to change the gear ratios in a 968 LSD?

Thom

I can supply gear sets to modify the ratios in the 968 gearbox. PM or e-mail me if interested.

ETA : sorry, just sold my last spare set today shortly after I posted. Will post again when I have another set available.

seattle951

Please post again if you get another set in. I am not in the market now. I am in the process of an overseas move.

I do not have the technical skills to the work myself. If I have the work done in a shop, what is a reasonable price point for parts and labor?

I like the idea of a 6-speed, but the ratios are completely wrong for my motor.

mikey_audiogeek

Ultimate to me would be an S2 box with a separate 1:1.2 stepup (overdrive) epicyclic gear unit built into the trans bellhousing.

This would take the place of the TT coupler, would be very short and compact, and increase the speed of the whole trans therefore increasing engine horsepower/torque capability of the trans in proportion to the stepup ratio.

The unit would be mounted on a 6mm thick plate that sandwiches between the trans and the TT bellhousing, thus adding minimal length. Self-contained oiling system, or port to the trans.

Conceptual design looks feasible, don't expect it to progress tho...

Cheers,
Mike

333pg333

You gotta get out more often Mikey!

Actually ultimate would be a good SQ with paddle shift. I know of 2 of these being installed at the moment.

George D

I agree. The 2 hour clutch job makes this the best choice for that reason alone. I can't go WOT in first, but 2nd on does hook up once GOOD performance tires are used, well sorted suspension, etc. The 968 boxes are stronger and the CMS Side Covers add much more strength. With a good LSD, short shifter, etc. I prefer the 968. They also make side plates for the 5 speed box, which is very popular in the kit car markets. There is more work towards conversion, but you'll see a payback on the first clutch change. You'll also have the ability to use a standalone using the factory trigger wheel, huge to me, and I'm a proponent of using as much factory parts as possible.

Finally, you can use a 911 TT Sport clutch in the 968 trans. Butter smooth, and will hold more tq than any aftermarket clutch I've used on my 5 speed cars. This was always a sore contention towards chatter, smooth shifting, tq holding ability etc.

Everyone that's driven my car with this setup was immediately impressed with the peddle pressure, and overall drive ability.

Hope this helps.

George

nick_968

I like the short ratios of the 968 box for my 3.0 turbo but then I already had it as my car is a 968. Thoms setup is probably a good option - more so if you can drive it on the autobahn as he can!

George - did you do anything to reinforce the firewall to deal with the extra force from the stiffer clutch plate? When I spoke to Powerhaus about this a few years back he said they had experienced issues with the firewall with that clutch. I currently use the 993 C2 pressure plate with the 968 friction disc. Is yours all 911 TT or just the pressure plate?

964-C2

What will the gear ratios be with this set up versus the turbo/S2/968 boxes?

Thom

I am curious how much of a clutch-unfriendly ham-fisted driver it would take to justify going through the hassle of replacing the whole flywheel+cltuch+bellhousing+torque tube to justify saving a few hours of work when the clutch is a unit that should normally last for several tens of thousands miles.

That's not the feeling I have had so far using both trans on my car, the 5 speed never opened since it left the factory and the 6 speed having been built by a specialist usually rebuilding trans for Cup cars.

A proper tuner will be able to make the 951 trigger wheel work with a capable aftermarket EFI.

thingo

I'm wondering what sort of ECU that tuner is using to get the 951 stock trigger to work, it can be very problematic.

Weston Dillard

2400# 425TQ 3.0L Track only

I thought the 6 speed would be too much shifting, but I think it works great with standard ratios. I do not run out of gear at TWS (either direction) or COTA.

All I changed to run 968 box was trans and left side drive axle. I spaced the trans mount down about 1/4 inch to keep shift mechanism from rubbing heat shield on tank. Been run hard for 3 years, all good.

West

333pg333

That would be the Link/Vipec platform although not everyone has got that to work perfectly. I think it's almost a matter of luck at times. Some people's seem to work, others don't.

2400lbs...is that with all fluids West? Lexan front screen? Sounds really light.