early_grayce

I'm in the market for a track car and currently entertaining a few options. Included are a couple 964s and RSAs, but not all have LSD as an option.

I'm an intermediate driver, but planning on taking it more seriously over the next couple of years.

How "advantageous" or important would it be to have LSD? I've done plenty of searching and it certainly seems to be a good thing, but I couldn't get a feel for how much weight it should have when picking a car.

Thanks in advance

LVDell

You can add the LSD if you need to. The LSD is great thing to have. Really allows for power to be put down.

John H

If it is the original LSD in the vintage of cars you are looking at, it will probably need to be rebuilt/replaced anyway.

PedroNole

LSD= essential

I agree with John in that, depending on the LSD in the car you buy (age, manufacturer, type), you may be just as well or better off adding it after the purchase.

va122

Absolutely, when i was turning a 96 into a race car the stock LSD fried in the second day of testing.

Geoffrey

I wouldn't worry about whether or not the doner car had an LSD or not. Any street LSD (including GT3) will not last but a few events on the track. Buy a PMNA or Guard LSD and add it.

schwank

I sure prefer it. If you find a car with LSD and it is similar price, I would take it. A Guard LSD is about $2500 new just for the diff. That does not take into account installation and the other trans 'while you're in there' stuff.

It really helps you get on the gas earlier in tight corners and can make braking more stable as well.

Gasser

If you end up buying a car with out a LSD, I have the old one out of my 993 that is avail. It needs rebuilding but otherwise fine.

Jeff

Gary R.

Geoffrey - How long do you think a stock LSD in an SC will last before needing attention? Is there an easy test?

Thanks

Veloce Raptor

Yup. 911's need to be on the power early early early in the turns. Anything which facilitates this is good!







Professional Racing and Driving Coach

Geoffrey

I have no idea about 915 transmission components.

Bill Verburg

thru '83 the ZFs were somewhat more robust than the '84 -86 versions.

the early versions could be configured to nominal 40% or 80% by stacking the driven/drive plates differently, the actual breakaway torque can be controlled by that and the preload fromm varying disk thicknesses. The '84 -86 are less resiliant in this regard, more like the later street lsds used in g50s.

GT has even more robust friction plates available for these units.

Gary R.

Thanks Bill.

MarkM

Gary, the easy test is to drive slow tight circles in the paddock. If the rear wheels aren't popping, they are too loose.

I always had my 915 checked/adjusted at the begining of a season, and did 6-8 events a year.

M758

I have driven and race my 944 spec car for 8 years with an open diff. I have even won few races during that time and set a few track records with a couple still standing. So you can go a long way with an open diff. However the car will be faster with an LSD. How much faster depends on how much you can dial out wheelspin and manage it under trail braking.

Point is while and LSD is great to have you can still have alot of fun without one.