What I would love to find is a supplier of different gear sets for the 951 box. I've seen Powerhaus gearsets for 3rd 4th and 5th. But what would be the ultimate is an active 5 spd. In other words a really steep first and then an even spread over the rest of the range. I've had this on other racecars I've owned and the difference in incredible.

 

By active, do you mean that the 5th is not like an overdrive type gear? I think if the car is light enough and has at least 350whp the stock gearing would be fine, but on a track car that might not be quite good enough. I can also suggest as at the very least a good stop gap mod, to swap in the S2 wheel and pinion into the 951 box. This really livens the response up nicely. Of course it reduces your top speed, but few of us need to go to 165mph.

 

When switching the S2 R&P, you have a very similar ratios to the 968 box.

This is a hard decision. I've found a 968 box that may not require extensive rebuilding, or I can rebuild by 5 speed. I'm conflicted with what to do here.....wish these cars were easier to deal with.

What I really want is a 968 box with a 3.0 R&P, I think...LOL

Anyone know the specs of the factory 968TS box?

Thanks,

George

 

The 968TS has a higher 5th and 6th, though alternate ratios are available for the 968 box.
I've used both boxes, the 968 has better ratios(closer) has a better shift and has a better lsd(more plates).

 

That lsd is only in 92 boxes which from what i read had the R&P issues. from what ive read, in 93 or for 93 they changed to a torsion diff.

Anyone have a 968 torsion they want to get rid of?

 

As long as we have hijacked this thread, can anyone give any firsthand experience about how to get the speedo working with a 968 box? I suppose you can wire into the wheel sensors. But I believe you can also swap in an Audi sideplate and speedo drive? Anyone?

West

 

George,

Is this a race car or a street car?

In any case, I suggest you drive a car with a 968 tranny. They are really geared for towards a car with a narrow power band (like the 968 has). Lots of shifting.

If it's a track car, your lap times would be far better with a 951 5 speed with a Guard LSD than they would be with a 968 box with either the Torsion or the factory LSD. And I don't mean a little either... Plus while the closer ratios of the 968 box might get the car on the turbo faster, which would "feel faster", you have to shift more, and that takes time (too much). Plus, with an engine like yours, I can't imagine your car would be having a difficult time pulling like a freight train in 5th gear anyway.


Oh... BTW (shameless plug) if you do go with a Guard LSD and use a factory oil cooler on a 951 transmission, I've got a brand new Guard oil pump drive gear that I'll give to you 1/2 price :-)





TonyG

 

Tony,

BTW, thanks for the PM. This car is a street/DE track car. I drive it a couple of days a week on the street, and occasional trips to the mountains, San Diego, and Phoenix for track events. I'm one of those that runs what I brung. If the five speed is the best box, we'll build a better one for this car.

The car is getting 10spi boost in 5th at 3K. From 3500K on up the car really pulls hard. I've driven many, and owned many fast cars. This thing just effortlessly pulls. It's not a boost hit, just a steady push on your backside. The push gets stronger as the rev's climb. 500WHP is addictive. I've been keeping it at 15psi and 430 or so WHP on the street.

We will resume tuning when I get a FU**** transmission installed. I get so frustrated with these cars at times. When I needed a transmission for my M3, one call and here in two days. Gearing changes, no problem. Stronger box, no problem.

I'm ranting, but this is frustrating.

Tony, can you get a deal on a Guard transmission.

George

 

OOPS, meant Guard LSD Diff.

G

Tony, can you get a deal on a Guard transmission.

George[/QUOTE]

 

George,

I do the "run whatcha brung" thing with my 951V8 so I completely understand.

With a 2.5L running a short track, I can see the advantage of having the closer ratios of a 968 box. However, the S2 tranny with it's shorter R&P almost works equally well on the tight tracks. On a fast high speed track... it's pretty easy to keep a 951 on the boil no matter the engine so I'd rather keep the wider ratios and keep the engine in the meat of the TQ curve as long as possible and benefit from less shifting. It's amazing how much time you lose shifting. You really need to run a GPS track mapping system to see how much time it costs to shift the car.

Like I said... you should drive a 968 around on the street.


As far as the Guard diffs go. I jumped through a stupid number of hoops to get setup as a dealer for Guard. So yes I get dealer pricing. But it's like $200 off retail. Almost not worth dealing with...

But if you're running the track I can promise you that you will knock at least a second off your lap times going with a Guard 50/80 LSD (if not more). They totally change how the car handles under braking and corner entry. That's what I was told, that's what I read, and I would not have believed it myself until I tried it. I'm a believer.



TonyG

 

By an "active" 5 spd, it means all 5 gears are useable on the track. Imagine if the first gear is ratioed perfectly for the slowest corner on the track, and 5th is perfectly ratioed so that you're just under redline at the end of the longest straight. Now you evenly spread 2nd, 3rd and 4th between 1st and 5th. All five gears are usable. Getting out of the pits is hard, but it is on any real race car.

 

Right I get you Lorenzo. Makes sense but so would changing out gearsets or trannys for each different track. I find that I mostly use 3rd and 4th anyway, but what you describe would be ideal.

 

Patrick,

Do you remember what company in Australia was making the 3.0 R&P for the 968?

George

 

I have a 968 LSD 6-speed in my 951. The car is running about 310 RWTQ/320 RWHP. The transmission improved the streetability of the car significantly.

However, I cannot shift fast enough in first and second gear to keep up with the motor at full throttle. When I want to go fast I usually step through first and second quickly to get to third.

I have used the car on DE days at the track and it does perform well in third, fourth and fifth gear.

 

I would think that you'd want to stick w/ your 5-speed and then give it a taller 5th. You've got such a wide powerband that you won't need the closer gearing, and for street driving you're just gonna get frustrated with 1st and 2nd -- they'll be over much too quickly. Especially w/ a 7k redline.

And for the track, methinks if you switched to the 6-speed you won't even be shifting often enough to warrant the "need" for the extra gear...



So'd you hear about Sean's problem now? Won't start after installing the new chipset. I'm supposed to loan him my DME tomorrow or today...hopefully he doesn't blow it.