Dave07997S

here is the webpage..go to the applications list.

Quaife Limited Slip Diffs.

I found them for under $1600, I want to thank dodd for the find.

Dave

PAULSPEED

Hi,
You still need to add the cost of dropping the motor and shipping the transmission
to a tech. place. I have a couple of friends who did this and it does
make a big difference.
Paul

Dave07997S

Actually you don't have to drop the motor to do this and from my understanding and what I have been told it's not that difficult. Very interesting...

I agree Paul, a locking diffy in this car will help. To bad we can't change the gear ratio.

Dave

dndodd

Paul,

I watched a Racing Mechanic change the LSD on a C2 from a bad to a good transmission. It looked very simple and straight forward. The mechanic was from TRG, they were preparing their cars at the local dealership for this weekends races at Barbers.

http://www.theracersgroup.com/

He said the only reason he was doing it out of the car because he had to change the transmission.

Otherwise doing it in the car would take 45-60 minutes for him. They definitely did not drop the motor to change the transmission either. It was supported by jack stands and still very much in the car.

My only question after watching him do it is does the new diff come with bearings mounted? I didn't think to ask him this yesterday but I will at the races this weekend.

Other than the bearing issue it looks like a very straight forward wrench job.

David

nkhalidi

Nice find, dodd.

I wonder how a mechanical LSD would interact with the 997's ABD. Comments, guys?

Edgy01

I suspect adding the PSD will completely alter the work Porsche went through with their PSM system. Perhaps they disable it,--I don't think they can work together.

PAULSPEED

Hi David,
My friend had a LSD installed by the racers group. You can talk to Austin about
the details. They took the transmision out because they sent it to a professional
to have the LSD installed. My friend tends to turn off the PSM. All in
the name of speed.
Paul

Dave07997S

Just got off the phone with Quaife (or their represenative) and they told me there were no issues with the PSM and PASM has nothing to do with the ABD anyway. Since all PSM is doing is applying the brake to the spinning wheel along with cutting power and such. If PSM is still active than the ABS will still apply the brakes to the spinning wheel with a LSD or not. What's nice about the Quaife is lifetime warranty and it doesn't cause understeer like a true locker would.

Dave

nkhalidi

So ABD is second in line to the mechanical LSD? That is, a mechanical LSD will preclude the engagement of ABD because the slipping wheel won't be slipping so much that ABD would engage?

dndodd

Paul,

Can never get enough speed. LOL The mechanic mentioned Austin to me. A profesional would probably pay more attentnion to the tolerances. In fact they mentioned a guy in Cincinnati who builds the LSDs for Porsche and I beleive the transmissions too. He may be the guy they sent it too.
The guys at TRG told me they only get about 3 races or 750 mile out of an engine, I suppose they wear out transmissions at very regular interval too.

David

Dave07997S

Good question...I would imagine the ABD is basically a open diff using the ABS controlled by the PSM will just apply the brakes to the spinning wheel. I still have more questions until I am ready to take the leap, I will pass on the info.

Dave

dstrimbu

That makes sense to me. If the LSD is mechanically distributing torque as it was designed to do, the ABD shouldn't see enough of a speed differential to apply the brakes... or so it should seem.

It would be cool to know more about this.

PAULSPEED

Hi David,

They run a lot of cup cars out of TRG. I think they told
me that the motors were good for about 10 hours and you
mail the motor back to porsche with 50,000 for a new sealed
motor. You need big pockets for Cup car racing. Just look at
how good "Lally" is doing in the Grand-am series. I would love
to drive a cup car around a track just once. The gear
shift is sequential and you push the stick forward to go up
a gear and pull back to go down. It is fun to watch them slam into a braking
turn and slam the stick back about 4 times.
Paul

Dave07997S

Unfortunately Porsche isn't doing so good this year. They finally won a race this year in Grand Am at WG. The Mustang and BMW are probably going to battle it out...looks like the Mustang will win again. What I don't understand about Grand Am is how can they let the Mustang use that 5.0L DOHC "Cammer" motor when it isn't even offered for sale on the production car. Yet Porsche is stuck with the 3.6 and BMW has to use just a bolt on S54 for the M3.

Dave

PAULSPEED

Hi,
As long as "Lally" wins the championship who cares.
Go Lally!!!
Paul