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Gtr Front Lsd. Who Has Used One?

Beer Baron
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Beer Baron Grand Master

Beer Baron

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hi guys,

beer baron is in the midst of upgrading my little ol car. i'm putting in my GTS4 diff gears. and I had a thought. since I am pulling front diff out and putting the CW onto the old open centre, why don't I buy a nice LSD centre to put the CW onto and instal that. But then I'm thinking, do I really want/need a front LSD. now obviously we can discount 2 way and even 1.5way as the turn in understeer I imagine would be insane. even more so if you like to trail some brake into corners. so basically we are left with 1 ways. I'm curious to see what people think of them. obviously for straight line stuff they are magic. but on the circuit what is it like when you are exiting a corner and get on the power early (say right at the apex). you probably still have a bit of steering on, so what happens? does it just grip up and point you where you want to go, or will it send you wide?

so if you have an LSD in the front of your GTR tell me what it's like, and is it worthwhile, or should I just stick with the open? also, any negatives? and what model have people used?

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Beer Baron Grand Master

Beer Baron

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well a 1.5way is a 2 way really. just different ramp rates on the decel side. but I'm fairly sure you can get 2 way lsd, but regardless I'm not interested in 2 way for the front.

Beer Baron Grand Master

Beer Baron

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ok, so ben has a 1.5way in his 33, but what I really want to hear is someone who has used one, or even just driven a GTR with one fitted (hard!).

curious to see what kind of effect it has on handling and whether that effect(s) will suit my driving style.

giant Mentor

giant

Posted
Posted (edited)

just kidding!! :(

we have a one way front, in our car. we found a very noticeable difference in traction especially from standing starts and off slow corners.

driving style has to be adjusted a little bit generally as powering on too much mid corner will cause some understeer.

but the pro's far outway the cons and if you see too much understeer there must be other issues.

our gtr seems to have super turn in, good mid corner speed and awsome speed off a corner with the front lsd.

to put it into context when chasing down an evo for instance on a tight track, we match there turn in and mid corner speed and much better exit speed generally!

cheers russ (p.s dont tell anyone!!)

Edited by giant
Beer Baron Grand Master

Beer Baron

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haha, thanks. you don't have to worry about me snapping at your heels just yet!

sounds good. I am prone to getting on the power perhaps a little too hard too early, but I can learn to deal with wiping out that.

what brand/model?

giant Mentor

giant

Posted
Posted

yeah , i get on the power a bit early too! but you get use to it quickly!

if you find you get to much under steer , let me know so we can try and nut it out! it wont be your front diff.

cusco 1 way! excellent upgrade ( we had read a fair bit about the cars getting understeer when fitted, but did not see that at all with our car)

cheers mate

Beer Baron Grand Master

Beer Baron

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ok cusco 1 way it is.

I think the unsteer can be cured simply by repeating over in over as I'm driving:

"slow in, fast out. slow in, fast out. slow in, fast out. slow in, fast out. slow in, fast out. slow in, fast out. slow in, fast out. slow in, fast out."

haha. but I always want to brake that little bit later which definately hurts mid corner and exit speed.

atm, turn in is super sharp. front: 3.2 degrees neg, about 9 degrees castor, 1.8mm toe out each side. rear is 1.8 degrees neg, 0.00 toe and traction rod set for a more upright upright. hicas locked of course.

I'm thinking about knocking back the castor a bit to about 7 degrees. make front toe 1.5mm each side on the front and maybe a little toe in on the rear as it's a bit hairy under brakes atm. razor sharp turning in, but I find my self backing it into corners a bit more than i'd like. particularly the big stops like just after the kink at oran park GP.

giant Mentor

giant

Posted
Posted

spot on mate 1 mm in on the rear will proably help settle the car down heaps under brakes and help keep the back in through the turn.

also using rose joints over bushes an absolute quatum leap forward in handling when your pushing hard, even in a straight line!!

cheers russ

Beer Baron Grand Master

Beer Baron

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for sure. I now run all rose jointed arms except for the front upper control arm. castor rods, traction rods, rear upper arms all rose jointed (nice big 3 piece bearings, stainless shell and tight silicone boots). front upper control arm is noltec adjustable arm as I didn't have much success with the dog bone type one. but the noltec one has been good so far.

Angus Smart Grand Master

Angus Smart

Posted
Posted

I have a sort of related question, my rear lsd i think is f**ked, the drive shafts have up and down movement when up on hoist.. which doesnt look natural. and a bit of shuttering from time to time..

i beleive its cusco which i will buy again, whats the best to get for the rear? 1.5 or 2 way? and can the old centers be rebuilt?

the front might be upgraded at the same time too. funds permitting...

9krpm Mentor

9krpm

Posted
Posted

I have an ATS 1.5 ways at the front. I've not notice any understeer at all. There shouldn't be much different between the 1.5 and 1 way because the amount of time I am on the brake is minimal. I only use the brake to shed speed, transfer the car's weight to the front, and as soon as the car starts to take the turn I am back on the gas way before the apex. I agree with Russell, it's a nice upgrade.

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