Russ Murphy

Something like that.

Danno

Also, since they are gear-based, they don't generate a lot of heat under hard use. Unlike friction-plate LSD, which require the clutch plates to be slipping in order to work. Someone on the email lists who've actually measured the temperatures of the tranny said that the torsen-LSD equipped cars had 20-degrees cooler oil temperatures.

Russ Murphy

Let me try this again.

Something like that.

Luke

I think I would have died about .........hmmm82times already if I had a locking diff. I'll have two open diff's pretty soon. I think I might try welding one.

JGriff

I recently acquired a 1990 S2, and the PO put in a 1989 Turbo S tranny (with LSD and oil cooler) after the OEM unit was damaged at a track event.

I've put up a page detailing the swap, including the differences in RPM/MPH for each of the gearboxes. This may help shed some light on the subject (i.e. whether 5th is OD or not).

On that note, what do you folks think of this swap? If you get a chance, please read the page, look at the charts (there is one page showing all RPMs and MPHs), and give me your thoughts.

Also, would this swap affect my odometer and speedometer at all, and if so, by how much? Would it be insignificant?

Here's the gearbox swap link:

944 S2/Turbo S Gearbox Swap

Thanks.

Jim

PrerYDoG

I think that your speed comparrisons would prove the point that the 5th gear is not OD, but an actual gear in the 951. I do think however that those speeds are off (or maybe I am off ). I did not realize that 2nd gear went all the way to 69, I thought it was 62ish.


Mark

Danno

I've got a gearing-chart of most of the 944-series trannies on my website at: 951 RacerX website

Looks like the S2 has all the same gears as the 951, except for a lower final-drive. So effectively, your 951 gearbox is about 14% taller than the S2 in all the gears.

So your speedo would now read 14% slower than you're actually going. Acceleration would be slower in each gear and top-speed would most likely be down because you're under-revving the power-peak at top-speed.

Porsche did a really good on matching the top-speeds of these cars such that the power-peak coincides with the actual theoretical top-speeds for the power-output of the cars. In most cases, if they had used taller or lower gearing, the cars wouldn't have been able to achieve their top-speeds.

Now in my case, with a modified 951, I'm finding that the gearing is too LOW now. I'm redlining in top gear with no more revs. What I really need is a taller 5th gear. Since the gears interchange across all the same series of gearboxes. Like all 016 gearboxes can exchange (924S/944/951) and all 083 (944S/S2), I can probably swap in a 5th gear from an '82-87 944 to get a 10% taller 5th which would be perfect.

PrerYDoG

Danno - Would are the gears in the 944 made to the same tolerances (i.e. rigidness) as in the 951? I know the 951-S had 1st and 2nd gears "hardened" as to prevent from stripping them with the added HP and Torque of the 951-S engine, would this also be a problem with 5th from a 944NA?

Danno

Due to the lower torque-multiplications in the higher-gears, I would think that 5th-gear from a 944NA tranny should hold up just fine. Problem is getting that 5th-gear. New one would cost more than an entire tranny used. Anyone have a trashed '82-87 944NA tranny they want to sell me?

Luke

I think finding somebody with a 10 ton press is as equal a challenge. I have a similar problem. I have a 4-5ish teeth missing off my 2nd gear and a couple off the one on top of it. I dont think it would be "feasable" to replace these gears when I can get a re-manned gearbox from Mr. Garrity for $1199.

PrerYDoG

Perfect time for a yo' momma joke.

Seriously though, what is the cost of a 5th gear? I think Ahmet goes through transmissions rather often, you may want to ask him for his 5th gear.

951and944S

Dan, and Danno, I,ve looked at the Quaife and Guard diffs, in hope of locating some element gears for this unit.
The picture below is of my "unidentified unit"..
I aquired it with the purchase of a salvage titled 951 I recently bought.
The PO of the car didn't know much about it.



This unit has "open carrier" as opposed to the views I've seen of the other units, which look more enclosed, similar to the factory LSD..

Any Ideas..? Would it be economical, to repair...? I can definitely do the repair myself, if I could find a distributor, I need six element gears...

Thanks

Terry

Danno

Check out the folks at www.torsen.com. They actually are the ones who bought the license from Gleaman and are the ones who built a lot of the OEM torsen-LSD units for Audis. Which coincidently, many of which uses the same 016 tranny as our cars.

So what's your ruling Terry? Is the Guard unit truly of "higher quality" as claimed than the Quaife unit?

Luke

those bearings looks nasty guy!

Alan C.

I put a Guard diff. in my 993 along with a set of Guard's close ratio gears. The diff. was a real piece of art. I took into our research lab's machine shop and showed the machine work to the guys and they were impressed. I sold the car three seasons ago and the guy who has it now has yet to blow the diff or damage the gears. Can't say the same for the rest of the car. He is rather heavy handed on equipment.

Alan