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Guys with the guard clutch lsd:how noisy is it during daily drives or in tight turns in carparks? I had a range of clutch type lsds in different cars over the years and they range from unbearable (car jumps on u turns) to mild clicks to no noise at all. Am cautious here as my 987 is going to be daily driven. Thanks

I have a guard tbd diff and makes zero noise, i assume the clutch types do make more noise than stock but not by much....
 
I have an OS Giken and it is 100% silent. I'm very happy with the OS Giken. It performs well. w/ great traction under acceleration and it tracks perfectly under braking. I'm told it runs cooler than others too, though I really have no idea...
 
Guys with the guard clutch lsd:how noisy is it during daily drives or in tight turns in carparks? I had a range of clutch type lsds in different cars over the years and they range from unbearable (car jumps on u turns) to mild clicks to no noise at all. Am cautious here as my 987 is going to be daily driven. Thanks
Noise is one thing. I'm more worried about how these clutch type LSDs react at the limit. Just because the wheels lock harder doesn't mean it suits an average driver. I'm skeptical about my driving skills, so I would rather stick to TBDs till I really know what I'm doing. Those 1.5way etc LSDs lock up very hard and may be very difficult to manage when things break loose.
 
I have an OS Giken and it is 100% silent. I'm very happy with the OS Giken. It performs well. w/ great traction under acceleration and it tracks perfectly under braking. I'm told it runs cooler than others too, though I really have no idea...
I just had one installed on my '06. I like it! Around town, there is no difference, even when making U-turns. I haven't been to a track yet, but have been out hooning with it on back roads. The big difference is that, before, while I accelerated out of a turn, one wheel would spin while the other did nothing. The car did not accelerate until I unwound the steering wheel and the inside wheel settled down. Now, I can be in the power band and just hammer the gas. It MOVES. It's making me develop some new skills dealing with this extra speed out of the corners. Very nice!

:cheers:
 
Noise is one thing. I'm more worried about how these clutch type LSDs react at the limit. Just because the wheels lock harder doesn't mean it suits an average driver. I'm skeptical about my driving skills, so I would rather stick to TBDs till I really know what I'm doing. Those 1.5way etc LSDs lock up very hard and may be very difficult to manage when things break loose.
Z:

I wouldn't worry about such things. If you doubt your skills, and there's nothing wrong with that, stay away from the limit. There's nothing wrong with that either, especially at a DE event where you're trying to learn things. One step at a time. If you remember that there are no race team scouts at your DE that will be picking you out for an F1 seat, the pressure will be off to race everyone. Just get the fundamentals in your head. After they're in your head, it takes a year or so to get them to travel out to your hands and feet.

Your car will be easier, not more difficult to control at the limit with an LSD. They're also easier to drive at speed with stiffer suspensions and more roll stiffness (to a point). Driving Buicks real fast is hard work!

Don't buy a full race diff for a street car. Buy the one they recommend for you and you'll be very happy with it. The guys at Guard are very knowledgeable at this.

I went with Giken and I'm happy with it because I don't do so many track days anymore. Too many distractions in my life now.

I'm familiar with Improved Touring BMW 2002s. Those guys used to take their open diffs apart and weld them together so there was essentially no differential. It worked great. Not so good for parking admittedly, but absolutely great on track. You could drive with one wheel in the grass and still have full power. That setup, btw, is called a "locker rear-end"....highly not recommended for a dual purpose car.

I'm describing the lockers because even those work better on track than open diffs. They weren't "tricky" nor would they try to spit you off the track. At low speeds they make the front wheels understeer terribly. The more diffs "lock", the more they don't want the car to turn. At speed, this goes away because the wheels are slipping all the time anyway. (look up "slip angle") Clutch type LSDs are tamer than those lockers. Companies like Guard can change the amount of slip in either direction (accel or decel) The whole point is to make them easier and more capable at the limit.

I drove an E36 M3 with 25% LSD on track for 10 track seasons. It was great. You could use the throttle to steer the rear wheels. When things got hairy, you floored it and kept steering the car. Lift while cornering hard and you spin.

No matter what diff you have, you don't lift in the middle of a turn except for some front wheel drive cars, and that's just for a breath to get the thing rotated a little. Read up on "trailing throttle oversteer".

:cheers:
 
I also installed an OS Giken about 6-7k and it's completely quiet on the street.

However when you really push the car, specially during tight turns and hard acceleration, you will realize how much better you are able to put down the power, it really transforms the car.!
If I ever get another CS, this would be the first mod I do to it.
 
I'm looking into replacing my factory PDK LSD as the stability control in the "off" position lights up coming out of slower corners on track. If I understand correctly the only company out there making one for the factory lsd pdk box is Guard. Are there any other options? They are currently out of stock at the moment.
 
If you are running 275/35 or 285/30 x 18's RE71R's in the rear that are in good shape, the grip of these tires almost make a LSD moot. The suspension is much more important with RE71R's or Hoosier tires. Maybe trail braking from 130 to 40, lap after lap, the LSD may pay off, but with our limited HP, suspension is the key. I was recently in a PCA sponsered back road tour following 911's and GT4's, these tires were the equalizer, no wheel spin at all. I have Ohlins, Tarett swaybars, corner balance, lowered 30 mm and wide monblock forged wheels to keep the wheel/tire weight light.
 
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If you are running 275/35 or 285/30 x 18's RE71R's in the rear that are in good shape, the grip of these tires almost make a LSD moot. The suspension is much more important with RE71R's or Hoosier tires. Maybe trail braking from 130 to 40, lap after lap, the LSD may pay off, but with our limited HP, suspension is the key. I was recently in a PCA sponsered back road tour following 911's and GT4's, these tires were the equalizer, so wheel spin at all. I have Ohlins, Tarett swaybars, corner balance, lowered 30 mm and wide monblock forged wheels to keep the wheel/tire weight light.
+1.

I'm completely stock with a Tarett GT front swaybar and zero issues with wheelspin with ZII, ZII* or RE-71R. The standard eLSD works pretty fantastic when coupled with Sport Chrono, too; if you look at the free-body diagram of the way the brake system works, the forces are literally identical to that of a clutch-type diff, but it's actually better because you don't get the tight-radius chatter with an eLSD as with the clutch type. The biggest drawback seems to be rear brake heat and wear on the track, but even that can be minimized with a front swaybar and good rear tires.
 
So in 2020, a new year and for me a new solution to getting off a tight corner at almost full throttle. Currently, this would activate my PSM and delay my car about .5 of a second for that run. If I turn off the PSM, then I could get out of the corner with some inside wheel spin. For the past year, I have used the slip angle of less than 9% to keep the car from triggering the PSM. With a new LSD, Wavetrac, I can have both the PSM on or off, yet get more boost out of the tight corners. For slalom features, Wavetrac works wonderfully as well. So, now I just need to make my
appointment to get the Wavetrac installed. Not a bad price of $1245 with free shipping.
 
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So in 2020, a new year and for me a new solution to getting off a tight corner at almost full throttle. Currently, this would activate my PSM and delay my car about .5 of a second for that run. If I turn off the PSM, then I could get out of the corner with some inside wheel spin. For the past year, I have used the slip angle of less than 9% to keep the car from triggering the PSM. With a new LSD, Wavetrac, I can have both the PSM on or off, yet get more boost out of the tight corners. For slalom features, Wavetrac works wonderfully as well. So, now I just need to make my
appointment to get the Wavetrac installed. Not a bad price of $1245 with free shipping.
Did your car come with factory LSD?

Also, am thinking, would better push off from the rear in putting down power, give you a sense of under-steering?





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Car has an open diff. The Wavetrac is a middle of the road gear type ATB LSD, not a clutch type. So, from a maintenance point it will last a lifetime of the car. It will improve the throttle on traction out of the mid corner, especially if the inside tire is highly unweighted. Where the fuzzy part is the motor compression/deceleration effects on the handling. Others have commented that the understeer out of the corners is not a big issue with this LSD as it's not a locker and the suppose threshold brake wiggle is not apparent from compression, so pretty neutral on trail braking.

"Lastly, one of the most underrated benefits of the Wavetrac is its smooth delivery of power near the limit. Its patented design makes for a very predictable, smooth addition of power when you need it most - when things are at their limits: on the edge of traction mid-corner and using throttle to keep it there; or coming into a corner a little hot, but quickly back on it to maintain exit speed..." quote from a product descriptor on a differential web site.

Croc'd - Dave, any update from your personal experiences? What about the wet traction? Trail braking, then throttle on mid corner, any upsetting power delivery traction issues?
 
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I haven't driven the car too much lately, nor in the wet, but I did feel it kick in while under power (a little early, TBH) exiting a 90° turn on my commute. Previously, I'd have felt PSM intervene, but this time there was no discernable PSM activity. The rear just hooked up and powered out. I'm looking forward to your driving impressions. My next A-X is over a month out, so as of now I've only got a grand total of two runs of aggressive driving (@~1 minute each) to form any comparison.

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Ok, I am putting together a parts list for my local speed shop to install including Wavetrac. So, I will let you know some of my experiences, up and down a local hill that I find challenging, where wheel spin occurs in numerous areas, setting off the PSM. On the downhill, i will try to figure out if Wavetrac makes the rear more stable on trail braking, then on the gas midway through the corners. First AX is practice later in Feb, most likely in the wet.
 
After the first autocross practice session, which is run the same as the actual event, only it does not count the yearly point total. The weather was rain in the early morning with drying conditions. I ran old RE71R's but have heat cycle issues, tread still ok. As it turns out, I ran in the afternoon and could use all of the traction that these old tires could provide and then some. Others in my class were going for top time on their Hoosier tires. Left me behind.

So I really had to figure out the rear end. What it appears is that the LSD was putting down the power to the outside tire more than in the past with the open diff. This transfer of power across the diff from the inside axle to the outside gave more traction to both tires. I perceived this as not as much acceleration, but in reality it was seem less, faster and in better control. So, I just need to lift my game and push on the throttle earlier. Never got out of line even with wet patches on the ground and the slaloms seemed easy to navigate. No issues with the balance understeer or oversteer here. It's almost like I need a Sprint booster to push on the throttle harder with the added traction available.

The take away is with Wavetrac, you gain a larger margin of error, (like a rounded curve in torque/power delivered not so much as a spike) so I need to take throttle modulation to another level, closer to the cones and just faster through the course. Brakes work without any interference from the Wavetrac as far as I can tell.
 
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Interesting notes. I'm thinking that some time on a skid pad would be beneficial to learn the car's new behavior at the limits of traction.

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Just wondering if the Wavetrac redistributes the torque when there is mismatched back wheel speed to the outside wheel so both wheels are pushing harder. But it's almost seem less and unnoticeable because the PCM does not activate due to the slip angle being managed nicely and very little wheel spin. My installer said he thought the LSD was tight, meaning more HP/Torque to transfer power from the inside wheel to the outside through the interior gearing. I mistook his reading as needing more effort to push the car forward.

Another solution is to install a Sprint Booster and use the track settings, or simply push the throttle on earlier and harder as the tires can take the additional torque.
 
The ring and pinon were not changed. I am talking about internal resistance reducing HP/Torque to the wheels when cornering. Take a look at how many gears are actually turning to make the inside wheel produce power.
 
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