Frank 993 C4S

+1

Much better learning experience in a momentum car. Plus people usually invest too much $$$ in the car in comparison to what they spend on getting instruction/coaching.

AEsco48

I have the same symptoms on my 2007 997 GT3 with 45,000 miles, it does have a LSD but I am told Porsche has the ramps/% split backwards... Can some one explain?

I would understand if the opinion is that Porche does no have the % at ideal, but to have them backwards... What went wrong? Why does the 997.1 and 997.2 both have this issue?

Manifold

If you have factory LSD and have been tracking the car, the LSD will likely wear out within 10K track miles, leaving you with an open diff.

996FLT6

If stock internals on Porsche LSD they are pos brass which wear fast if u do quite a few trackdays. Lost mine at 11k. U can have it rebuilt with more durable internals like Guard Transmission. I think the 7.1 have the 28/60 whereas the 6.2 has a 40/60. U mite want to build with a 40/60 pack. Mike

Martin S.

On my 993, I had the LSD rebuilt by ANDIAL back in the day...after about 6 track days, possibly fewer as I recall, the LSD was "toast". I then had the LSD pulled and sent to Guard and upgraded to 4 plates VS the stock 2....I believe these #s are correct. Have not touched it since...been years, been many, many track days...still going strong it appears.

There is some sort of a "test" where one hub is held stationary and the other rotated and the torque required to rotate the other wheel is noted, or so I recall. This may be a hallucination on my part.

996FLT6

Really not a true test unless u open it up but jack up one rear wheel and in neutral with no ebrake make sure u put a piece of wood in front of tire to prevent car from rolling. Try to manually turn jacked up wheel Clockwise or Counter Clockwise- should be difficult to rotate wheel if LSD is working. My stock oem LSD rotated either way easily. Put in a while new guard LSD it rotate say 3 inches then stops rotating. Mike

KaiB

I just figured out what you were asking. It's not an issue, but rather a design feature.

LSDs in Porsches generally will offer more performance (i.e., lockup, biasing or whatever term you want to use) during braking than they will under acceleration. One often reads about 40/60 or 50/80 splits (let's not worry about what the numbers mean here).

Non-rear engine guys will often indicate that this is "backwards" or a "less than ideal %", but this works in our cars just fine.

Unless, of course, you're in a 935...

trackjunky

996FLT6, I think you should post on every page of this forum. Those pictures...............Ah....

Now back to your regularly scheduled program.

+1 on the LSD (had the same issue with my 996)
+1 on the dedicated track car other than a Porsche. Replace brakes on a Miata vs a P-car and you'll understand the long term value of not running a P-car on a budget.

Martin S.

"Really not a true test unless u open it up but jack up one rear wheel and in neutral with no ebrake make sure u put a piece of wood in front of tire to prevent car from rolling. Try to manually turn jacked up wheel Clockwise or Counter Clockwise- should be difficult to rotate wheel if LSD is working. My stock oem LSD rotated either way easily. Put in a while new guard LSD it rotate say 3 inches then stops rotating." Mike describes the "test" I was thinking of. BTW, as I recall, extracting the LSD can be done without dropping the transmission...I think, could be wrong.