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Is there a front LSD available for RS4 ?

I'm looking for a torsen or plated diff, but I could not find any info about it.

I've only seen one guy, duud_40 in Romania make an LSD for the rear but not seen any others eslewhere. BTW duud is selling his RS4 so his LSD is for sale.

P_G wrote:I've only seen one guy, duud_40 in Romania make an LSD for the rear but not seen any others eslewhere. BTW duud is selling his RS4 so his LSD is for sale.

I'm looking only for the front one.

Not seen anyone make an aftermarket one then.

I thought the Auto braking on the individual slipping wheel would act like an LSD

Ice_Coffee wrote:I thought the Auto braking on the individual slipping wheel would act like an LSD

It will act "like" but exactly opposite. It will slow down the wheel but not give extra power to the wheel that has the grip.

albertsz wrote:It will slow down the wheel but not give extra power to the wheel that has the grip.

When a wheel spins on an open diff it takes all the torque, making the non-spinning wheel useless.

When the EBD brakes the spinning wheel it stops the torque all going to the spinning whell and restores torque to the non-spinning wheel - which then gives you forward motion.

With the Torsen centre diff and 4 wheel EBD so long as one wheel has grip it will get a fair share of the torque and be able to move you forward.

PetrolDave wrote:
When the EBD brakes the spinning wheel it stops the torque all going to the spinning whell and restores torque to the non-spinning wheel - which then gives you forward motion.

When we put right wheel on ice and left on gravel. It will brake the ice wheel but it wont move the left wheel on gravel.

It is not about braking the spining wheel, it is about giving power to the wheel that does have grip.

Which ESP and EBD combined will do, but perhaps not as much as you are looking for?

P_G wrote:Which ESP and EBD combined will do, but perhaps not as much as you are looking for?

It will maybe do something but it is not how LSD's work. If you are really about performance than LSD (Torsen or plated) is the only way to go.

albertsz wrote:It will maybe do something but it is not how LSD's work. If you are really about performance than LSD (Torsen or plated) is the only way to go.

For the purist engineer you're 100% right.

But in the real world where cost is an issue, ESP + EBD is a sensible compromise. And one which seems to have been very satisfactory indeed in the recent snowy and icy conditions... I don't recall any posts on here of people that have been stuck in their RS4, only the opposite.

That means the market for a front (or rear) LSD (Toprsen, Salisbury, WHY) will be very limited, and likely to not be of much interest to most manufacturers and/or specialists.

What we have in the RS4 is so much better than most other vehicles that the room for improvement is tiny. Good luck finding someone offering a front or rear LSD - there won't be many, and you'll most likely need depp pockets.

PetrolDave wrote:

albertsz wrote:It will maybe do something but it is not how LSD's work. If you are really about performance than LSD (Torsen or plated) is the only way to go.

For the purist engineer you're 100% right.

But in the real world where cost is an issue, ESP + EBD is a sensible compromise. And one which seems to have been very satisfactory indeed in the recent snowy and icy conditions... I don't recall any posts on here of people that have been stuck in their RS4, only the opposite.

That means the market for a front (or rear) LSD (Toprsen, Salisbury, WHY) will be very limited, and likely to not be of much interest to most manufacturers and/or specialists.

What we have in the RS4 is so much better than most other vehicles that the room for improvement is tiny. Good luck finding someone offering a front or rear LSD - there won't be many, and you'll most likely need depp pockets.

If you wan't the most of your car on the race tack this is the only way. For street fun ESP + EBD is ok.

I have found some company in Germany that offers front and rear LSD for RS4 B7. I will post more info after I get confirmation.

I have tracked many different cars and an LSD is not always a straight yes choice as there are downsides.
Depends really on the track, grip and engine power. I've found that in general unless you are running alot of power with 2wd. With the rs4 I'd be very surpised if a front LSD would make any noticeable difference. Under normal circumstances it's a 60/40 power split so you're talking less than 160bhp before losses to the front.

adsgreen wrote:I have tracked many different cars and an LSD is not always a straight yes choice as there are downsides.
Depends really on the track, grip and engine power. I've found that in general unless you are running alot of power with 2wd. With the rs4 I'd be very surpised if a front LSD would make any noticeable difference. Under normal circumstances it's a 60/40 power split so you're talking less than 160bhp before losses to the front.

on track every tenth of a second counts. If the wheel is in the air than the other wheel will not put any power to the ground. Clutch LSD solves that problem. Torsen will put the power to the other wheel only if the other has minimum grip.

For street fun rear clutch LSD would be recommended just like in M-Power cars.

albertsz - Sounds like you bought the wrong car, since you want to completely redesign the powertrain.