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LSD's have a higher diff ratio i thought? and makes taking off from the lights much faster.. also the obious will always get power down to both wheels rather then just dumping the clutch to just get 1 spinning.. and getting rolled by a car with a lsd off the line..

thats my understanding anyways.. i would go a gtst diff i hear those things are tuff.. keep in mind if u get different ratios ur speedo will be off so might need to get that recalibrated..

Leigh

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if you do a burnout with a non lsd car on grass it may still spin both wheels. even on cement it may still spin both wheels. my old falcon had an open centre diff and i did a burnout on the driveway and it spun both wheels.

the most reliable way to check is to jack up the back wheels and turn 1 wheel. if the other wheel turns the same way as the wheel you are turning then it is an LSD, if it turns the opposite way then it is open centre.

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if i wanted to make it lsd for 2 wheel spinner, wohat would i get, gtst lsd? orr?

If you get an entire LSD unit from a GTS-t then it will have a lower final drive ratio. You'll lose acceleration in-gear, although each gear will stretch to a higher speed.

Not particularly recommended, unless you find that you could do with a bit more speed in each gear.

I'm pretty sure that Skylines have the speedo sensor coming out of the gearbox, so changing your final drive affects your speedo reading.

What are the advantages of having a LSD ?

In Nik's case, when you rip a skid you're more likely to leave two black marks on the road instead of one.

From a technical standpoint, you're less likely to break traction on one wheel as power is sent to the other that isn't slipping. With an open diff, power flows through the path of least resistance. If one wheel starts to slip, it gets more power. This means it slips more, and the wheel that isn't spinning gets less. Eventual scenario is that the free spinning wheel ends up getting all the power and the other wheel that has grip just sits there doing nothing.

LSD's have a higher diff ratio i thought?

A diff in a turbo car will nearly always have a lower final drive ratio than its NA counterpart if the displacements are the same. With less torque, the NA engine has to be kept up in its rev range while the FI car can use the extra midrange oomph from the compressor to make up for it.

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  • 2 months later...

i had a guy at the tranny shop say tht if it goes the opposite its an lsd so i jacked it up when i was working on it and did it and they went the same then when i finally got it on the road (completly gutless mind you and there were no cars around) i sidestepped it only chirped and felt like my side then when i went and did a skid both were going then when i got off the brake and held my foot flat it did two little drifts then died ????

my gearing is really really tall what speed does first gear normally get you?

Edited by LUME
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is there any visual differences? like the fins or sumthing when ever my car drives in the wet or if i rip one it slides almost instantly and if i did a burn out it left 2 black even lines, so do i have lsd? or just a lock diff?

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how about a mini-spool, would this affect the gear ratios...

It doesn't affect gear ratios as the construction of your differential is independent of the ratios. The ratio for each gear in the gearbox is obviously unaffected.

Inside the differential is a final drive gear, which affects your actual speed relative to the engine speed in each gear. This gear has a certain ratio. You can make it any ratio you want (within reason), so whether you keep it stock or change it is up to you.

and is it good/bad?

A mini-spool is a locked differential. Both your driven wheels will spin at the same rate, no matter what. It's great if you just want dry weather traction above all else, especially in a straight line. Track cars, like drag cars V8 Supercars, run fully locked diffs (but they'll probably use a full spool since it's stronger).

The bad sides are that the car will understeer more, you'll skip the inside tyre around bends so life is reduced, and since both wheels spin the same way chances are both will break traction at the same time. That can be problematic in the wet.

If you must have a fully locked diff, I'd suggest a "Detroit Locker" instead. While under power it behaves like a completely locked diff, but when not on the throttle it unlocks. That means that you can coast through a corner without chirping the inside tyre, or spinning out in the wet.

It's a very compromise kind of system. Tearing up to a bend and turning in with a reasonable amount of speed so you can coast through it, and not touching the gas until you're practically straight, can make you look like a bit of a git. Since it goes from fully open to fully locked the transition can unsettle the balance of the car if you get on the gas before you get it reasonably straight.

If you were building a drag car that you had to street drive to the venue I'd suggest it. Otherwise, I just don't see it as being a particularly good idea.

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Of the cars ive driven with mini spools and even welded diffs, wet/dry condition, neither are all that bad, as long as you are aware that you are in fact driving a car with a locker and dont try to be a hero around corners in the wet, its fine. Even in my mates S2 rx7, which isnt exactly heavy in the arse end. with a welded diff is fine in the wet and that diff has been welded for around 2.5 years.

Obvously an lsd would be a much better option by far, but getting the welder out can be a good way to learn how a car behaves when boths wheels are spinning evenly.

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