fifty wrote:
I ruled them out based on this: the need for periodic maintenance. There are no wear parts in a helical LSD, but the clutch packs are a wear item.
This is true - but the periods are pretty long from my admittedly very limited sample. I have been running ZF clutch diffs (BMW OE) for a while and they take multiple seasons of racetrack abuse. I run approx. 30 track days and a few races every season. 100% track, no street driving at all. The diff in my car is still holding strong on it's third year and I do make it squawk often because I am very stiffly sprung so any time a ponk a curb, drop a wheel or exit a slow corner with too much throttle I make it work. The last one made it 3.5 years but it had 80k on it when it went into my race car. This one was fresh 3 years ago and is showng no signs of weakness. Still holds 90 ft/lbs at the hub with a torque wrench.
I figure 3-5 years is pretty good for the advantage over the free-wheelspin stuff on a race car. If I raced a rear or mid engined car I would probably agree on the helical as they rarely lift rear wheels and when they do... you are already in a lot of trouble.
Ian F
SuperDork
10/19/11 7:35 a.m.
Interesting. Tran X doesn't show anything for a Sptifire. Gripper does, though... and it appears a US distributor for Gripper is a Volvo tuner in Oregon (I see Gripper also offers a Dana 30 version... )
Ian F wrote:
Interesting. Tran X doesn't show anything for a Sptifire. Gripper does, though... and it appears a US distributor for Gripper is a Volvo tuner in Oregon (I see Gripper also offers a Dana 30 version... )
I could have sworn I saw a Tran X one. Oh well must be going crazy.
Also aren't there some Salisbury differentials which fit the Spit?
What about a quaife for ice racing?.I've never used one but I have tried 3 combos in a rwd corolla used in the street studded class,open,welded and a 2 way kazz.The open was hands down far and away the best option,the other 2 were fine IF you had no traffic around you and could stay on the throttle all the time and you got the entry perfect every time.
Neither of those two things is very common in ice racing so they sucked.
In spite of what many folks assume, Spitfire 'jacking' does not involve lifting rear tires off of the road.
Stock, Spitfires exhibit very low rear roll stiffness. The addition of a Camber Compensator reduces the roll stiffness even more.
But if you are in a Spitfire and the rear end is jacked up into the air, then you are already well screwed, and spinning tires are the very least of your problems.
Carter
ww
SuperDork
10/20/11 12:55 a.m.
I have Quaife's in 2 of my race cars and NISMO CLSD's in one race car and one street car. These are all Datsun Z cars with rear wheel drive and properly tuned suspensions so I never lift an inside rear wheel which removes the issue with the torsion LSD loosing traction on one side.
I prefer the Quaife on the track because I feel like I get more predictable turn in. I like the Quaife on the street because it doesn't chatter on tight turns like the clutch pack LSD's.
Just my personal opinion. I'm sure there are a myriad of experts on this and many other boards who will point out the error of my ways. I doubt my experience in racing since 1986 counts for much but I prefer the Quaife.
I have the spitfire limited slip out of that same car you just bought the JK Jackson motor from. Full rear with a stiffer spring (added a leaf I believe). No idea why style limited slip in it. Yours cheap if you want it. Located in Daytona Beach but may be able to meet part way for gas/beer.
sergio
New Reader
10/20/11 10:04 p.m.
doc_speeder wrote:
I had a Peloquin in my last Mk2 VW. As far as I know it's a blatant copy of the Quaife. The car was a DD and occasional autocross car. Made maybe 130 whp or so. The diff was AWESOME. Unreal how something so completely un-noticeable on the street can work so good autocrossing. Hit the apex, then NAIL it. No more wait, wait, wait, ok now I can go WOT. It just pulled the front end around corners.
+1
Different car here but same thing. For HPDE and autocross the Quaife is worth the money. Never had a problem with 2 cars that had Quiafes.
Greg Voth wrote:
I have the spitfire limited slip out of that same car you just bought the JK Jackson motor from. Full rear with a stiffer spring (added a leaf I believe). No idea why style limited slip in it. Yours cheap if you want it. Located in Daytona Beach but may be able to meet part way for gas/beer.
Possibly. I will let you know.
ww wrote:
I have Quaife's in 2 of my race cars and NISMO CLSD's in one race car and one street car. These are all Datsun Z cars with rear wheel drive and properly tuned suspensions so I never lift an inside rear wheel which removes the issue with the torsion LSD loosing traction on one side.
I prefer the Quaife on the track because I feel like I get more predictable turn in. I like the Quaife on the street because it doesn't chatter on tight turns like the clutch pack LSD's.
If you've got enough horsepower, you don't have to actually lift a wheel to overcome a helical. You're going to have a light inside wheel due to weight transfer in a corner no matter what. In my testing, the clutch pack let me get on the gas far earlier even on a relatively low-power car. You do lose that open-diff-style turn-in though.
I haven't had a clutch pack chatter on tight turns yet, but I've certainly seen it happen with the offroad pack.
In reply to Keith:
Is the OS Giken you're running a 1-way, 1.5-way, or 2-way? I'm curious about how badly the non-ramping-on lift-throttle types affect turn-in... Short of trying to stabilize a car that wants to go all lift-throttle-backwards-into-guardrail, I'm not sure why you'd want off-throttle locking (which suggests a hole in my understanding, not a flaw in the diff selection...)
1.5. I'm not sure what the GM Positraction out of the CTS-V is, but we use those too.
wspohn
Reader
10/26/11 11:19 a.m.
As has been noted, the fact that losing traction on teh inside wheel means you lose drive makes the Quaife a poor choice for an autocross car, which is doing mostly very tight turns with lots of unweighting.
I never used anything but an open diff on my TVR race car because the independent suspension got such good traction even coming out of a corner hard, I didn't really need one.
On the MGA, at a local track I could spin the inside wheel for 50 feet coming out of the hairpin. I have used a welded locker, but that has the usual disincentive for use in wet conditions and for pushing the car around the pits. I switched to a Quaife and I really like it. As long as you don't completely unweight the inside wheel, it works very well. I would note that it, like a locker, seems to result in a bit more understeer (although less than a locker does) so one needs to adjust or dispense with a rear sway bar if you run them.
I can only comment on 1900 lb car, 175 BHP experience, so don't know how that translates to different combinations or oddball suspension (like the Spit).