LSD Question

[FORMONTOYA]

When it comes to a turn expect OVERSTEER. An insert gets tricky in the rain...

Thanks for the 'heads-up'. I have not had a chance to really push the car through the corners yet and rarely drive the car in the wet. But it is nice to have an idea of what to expect before I do.

Jim

 

[DSMboostin15]

I have a '90 GS-T and I was wondering about a limited slip for it. Now I know that the AWD are the best, but the car was a great deal and is in great condition. I'm building it to be a daily driver with the occasional strip use so I'm looking for some sort of limited slip to help get the power to the wheels. I am putting down and estimated 220-230 hp down to the front wheel and I need to know if a LSD insert will act like a locking differential and cause my wheels to squeal when I'm driving around a corner in the city. Or should I just spend the money and buy a Quaife or Kaaz limited slip. Thanks.

 

[RossY]

No your wheels won't skip when your going around corners. The springs on the insert push on the spider gears to lock them in place when driving straight but when you go around corners the force just makes the spider gears turn despite the pressure exerted on them by the insert. I have the BM tranny insert and it works pretty good. Although it really doesn't compare to a true lsd

 

[FORMONTOYA]

I have the SBR inserts in mine and as stated it is not a true lsd, but for the price it is not a bad upgrade. I do not notice any abnormal noises when turning, works great in a straight line. And if your not going over about 325-350 whp then they should work good for you.

Jim

 

[DSMboostin15]

Thanks for the input. I was hesitant at first, but now I think that I'm going to go through with it.

 

[larsenracing]

I have my diff. welded solid I like it but it slips alot around corners. If I were you I would just buy a Quaif if you had the money. I really should replace mine but it works and was cheep I blew it up when it was stock then I welded it to make it solid for a quick fix at the end of the summer now I have only put like 1000 miles on it. good luck.

 

[dsm-onster]

I have the SBR inserts in mine and as stated it is not a true lsd, but for the price it is not a bad upgrade. I do not notice any abnormal noises when turning, works great in a straight line. And if your not going over about 325-350 whp then they should work good for you.

Jim

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I have the sbr insert and it works great. very consistant in straight stretch acceleration. When it comes to a turn expect OVERSTEER. which is odd for a FWD. But is very good if you know how to use it. Oversteer is why RWD cars drift well through te corners... remember: practice when you upgrade suspension. An insert gets tricky in the rain...

 

[FORMONTOYA]

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I have the sbr insert and it works great. very consistant in straight stretch acceleration. When it comes to a turn expect OVERSTEER. which is odd for a FWD. But is very good if you know how to use it. Oversteer is why RWD cars drift well through te corners... remember: practice when you upgrade suspension. An insert gets tricky in the rain...

I have a question: from your discription I would assume that you are talking about "power on" oversteer exiting the corner, but what about entry into the corner? I would expect it to be more stable under engine braking/braking upon entry. Does it still tend to have 'normal' UNDERSTEER the first half, then OVERSTEER the second half? Of course this can be compensated for with a little throttle control, but it would be nice to have a better idea of your experience before I'm heading backwards through the parking lot with 50+ cones trailing along.

Thanks,
Jim

 

[dsm-onster]

I have a question: from your discription I would assume that you are talking about "power on" oversteer exiting the corner, but what about entry into the corner? I would expect it to be more stable under engine braking/braking upon entry. Does it still tend to have 'normal' UNDERSTEER the first half, then OVERSTEER the second half? Of course this can be compensated for with a little throttle control, but it would be nice to have a better idea of your experience before I'm heading backwards through the parking lot with 50+ cones trailing along.

Thanks,
Jim

Hey, got your pm.

A typical FWD car in a turn: understeers during any point of acceleration comes back to a predictable "steer" when lessening the throttle. This sucks because you lose so much speed to keep the car in the curve. Even if you break rear wheel traction you never want ot break front wheel traction (the same as drifting a RWD car).

FWD with a LSD insert: I noticed that it steers normal coming into the turn (normal fwd oversteer as you accelerate; correct steer when letting off the gas). But, significant oversteer exiting (as you let off the gas trying to compensate for the original state of understeer entering the turn). Oversteer increases as I let OFF the gas. This can actually benefit you if you know how to use it. Accelerating after the apex actually pulls my car to the center of the lane. Also, the understeer is lessened in the entrance of the corner. So before the apex expect a typical FWD response to throttle except a bit less understeer, and after the apex expect to do the opposite of what you would need to do for a FWD car.

I am not sure about the mechanics behind these changes. However, until you practice enough, accelerate steadily as you reach the apex. I suspect that the transition point of ON throttle understeer to OFF throttle oversteer is different for each car (tires, shock wear, bushing wear, spring rate). The best feelings I get while pulling through a corner is when I've decided the correct amount of throttle and the correct angle BEFORE I enter it. Come in the turn high, but turning to the apex. Then every time you hit that corner Hit it faster and faster to see how your car will react, where you need to apply throttle, how much to apply. Your will no doblt end up coming out right in the middle of the lane (good for the most part). Remember a corner can drasticly change it's character after the apex with respect to before the apex.

Needless to say, I have to really be in the mood to play with the curves to jump on it in the back roads.

 

[FORMONTOYA]

Cool, thanks. Of course I will experiment with it when I'm able to get to the course. I have noticed in a straight line I have to show a little more finess with the throttle or I get some pretty bad wheelspin in 1st and 2nd (from the new 16g, not the lsd), and would expect it to be similar coming out of a corner also. However, it is nice to have a better feel for what to expect.

Thanks again,
Jim