Mark944na86

That's for a G50 968 gearbox -- won't fit into an S2 gearbox (despite what the ad says).

I've already enquired.

Mark944na86

Also, I think a useful convention is not call a torque biasing diff an LSD, but rather a TBD. Avoids confusion and arguments. Particularly since Guard sells both TBDs and LSDs.

Finally, despite the limitations of a TBD, I think it would be fair to say that a track car would be still be better off with a TBD rather than a stock open diff. As usual, how fast do you want to go, how much do you want to spend?

spoolin51

Great info Thanks TonyG

TonyG

ABS has zero to do with it.

And it's not a misbehaving thing. It's the same for all RWD cars.

On a track you need that rear wheel lockup (wheel to wheel) at the limit of adhesion to control the back end of the car. On the street, how often are you at the limit of adhesion? Never.. That said I guess a Torsen would be good for a purely street car or a car that sees lots of rain/snow, etc... But on the track, the LSD rules. And the asymmetrical LSD blows the conventional symmetrical LSD out of the water on the track because you can have a lot of diff lock under deceleration/braking and a lot less under acceleration (which eliminates the LSD induced push). You really get the best of both worlds.


TonyG

TonyG

Not by much....

I guess something is better than nothing.


But that something still isn't cheap. And it's certainly not worth the cost of the TBD and installation.

You'd be far better off with a conventional LSD, which could be had for less money.

TonyG

Eric_Oz_S2

Tony - thanks for the info.

So where is the best place to get a Guard (clutch type) LSD, and what are they worth? I'll be in California in May, can I pick one up there for a good price?

Alternatively, what does a used 944S2 LSD go for? Is it the same diff for all 944 models?

333pg333

Eric, get a quote from Guards on one for your car. Not sure but you could probably put it in your luggage on the way home. They're big but not enormous. Really I'd buy it and have them ship it. Prices down here are going to be somewhere between $3-$4k yet I'm sure that if you buy this same thing in the US it will be a good deal cheaper even including shipping.
Ours are the two 'Props' on the front rh and lh side here. 968 as 'Rake' in the middle and TBDs playing 'Second Row'.

There also seems to be a push for Giken LSD but not sure if they have one for our cars?

M758

I have raced my open diff car 944 spec for 8 years. For most of those 8 year I have been able to compete with LSD cars by adjusting my driving style and through set-up. However I have finally come to the realization that I just can't close that 0.5 sec gap any more. I can feel how I am getting killed on accel out of tight corner where I need to take it easy to prevent spinning the inside rear. That cause me to be sitting duck down in the braking zone at the end of the straight. For 10 years have been tweaking and adjusting trying to minimize this effect. I can do that, but overall that hurts lap times since the car is not as good elsewhere.

The obvious problem is on corner exit, however under trail braking I drove factory 40% lock up LSD 944 spec for 2 hours. It had some tire issues which prevent direct lap time comparison, but I can say the stability under braking was outstanding. It allowed me to go very deep on the brakes or just thow the car in without risking spinning. Unfortunaly tire probelms force me to minimize my trail braking so I could not take full advantage of this effect . However that showed me how much harder I had to work keep the rear end stable while trail braking. I figure with a good LSD (even factory 40%) will be able to run the same lap times easier and will less tire wear and once I learn to use the new limits be able to run faster. If I can find 0.5 to 1 second on my mid 1:13 laps it would make a world of difference and bring me from just outside the top guys to right in their pack lap after lap. Right I can run 1-2 laps a thier pace, but can't sustain that over a race distance because I think I am over driving the car to hit those lap times. Overdriving can work for a lap or two, but not for a race distance.

If all goes well by my April race I will have that problem rectified.

TonyG

You think a 40% lock made a world of difference? Try an 80% lock. That's what I have. It's a 50/80 (50 on acceleration, 80 on deceleration).

The trail brake passing is amazing as well as the ability to carry more speed into and out of each turn.

There are two specific turns at California Speedway (the infield) where I literally throw the car into the turn sideways to scrub speed rather than brake... and it's rock stable.

If you spent the money for one of those your whole driving style would change and you'd probably drop 2 seconds.


TonyG

M758

No way there is 2 seconds on the table using a 50/80 diff. Not for me or my car on the tracks I run. The cost of the diff vs a factory one is what keeps me away from it.

TonyG

I don't know about 2 seconds, but if you think you can close a .5 - 1.0 second gap with a 40% LSD (which is what I think you said), then you would definitely do much better with the 50/80

Did you read the POC eval on the Guard site under latest news. That's what drove me to it. And I'm a believer.

TonyG

333pg333

Yes but Joe, you're talking about 1.13 laps so that's a pretty short circuit. On a 2min plus track the difference will be greater.

333pg333

Tony have you got any links to the Guards stuff? I find that their site is 'Still under Reconstruction'.

M758

Yes I did. I believe in them, but not the claims of 2 seconds a lap. I have been struggling with their cost vs performance for years. I finally think the open diff is holding me back enough to make a difference. In spite of the fact I led 1/2 of the National championship race in 944 spec with an open diff I think it is time for me. I can't consider the 2k Guard so I working on the factory one. My guess is that it will bring the car back on pace.

333pg333

Ha, if you ever want to measure 10th of seconds vs $$ you'll go insane quickly &/or retire!!