Diff's - Whats The Diff? 1 Way, 1.5 Way, 2 Way

[evil_weevil]

Hi guys,

Just a quick one, you have a standard diff and a car that does mostly track days.

What is the best option to go for? My standard starts to open wheel and is hard to get some power down. I can get a rebuilt 1 way centre at a decent cost, but what do most people go for, for track days (not drift!)

Cheers,

Chris

[swanny180]

I found my shimmed up diff (added a single 1.2mm shim) was brilliant at Wakefield compared to the first time I went.

It actually began to open wheel towards the end of the day, and the difference was huge (the open wheeling was a result of the crownwheel bolts not being done up tight enough - this reduces preload on the shims - and take note that this was the result of human error, not a problem with shimming the diff). It was amazing how much longer you needed to wait when exiting a corner to get on the throttle when it was open wheeling.

It actually gave a really good perspective on just how much improvement it made in retrospect...

If you dont mind getting your hands dirty (its a bit of work to do), its a very very good value for money diff upgrade. $8 for shim, $20 - 30 for some new diff oil, locking diff for under $50 bucks... hard to beat

Edited April 3, 2008 by swanny180

[evil_weevil]

Cheers Luke!

Yeah thats one avenue for me to look into also!

So the 1.13 at wakie - that was with the shimmed diff? What times were you doing prior?

I know what you mean with the open wheeling and getting power down, but here comes a silly question....if it is more of a "locker", instead of open wheeling when putting power down, wouldn't the car more likely slide more if both wheels spin? Or with the locking, it helps give both wheels even power/traction down so it helps getting out of the corner better?

I need to do more research (diff's for dummies 101!)

[Beer Baron]

1.5 way is the go. 2 way is acceptable too. you could get a second hand GTR diff (which are 2 way) quite cheap and buy the nismo clutch upgrade for it and have a basically brand new nismo 2 way for cheap.

[nisskid]

comes down the preference, a 2 way will obviously lock up both on accel and decel so it makes the diff movement very predictable when coming on and off the throttle, hence why its popular for drift, this unfortunately means that coming in, middle and out of the corner the rear wheels arnt going to want turn at different rates on either acceleration or deceleration, this causes some understeer, especially coming into the corner and on the tighter corners. 1.5way allows u to feather off the throttle and open up the diff meaning it can turn in easier, but when u put ur foot back down it locks up again and allows u to get the power down. for me the 1.5way is preferable, but as i said, its about preference.

[evil_weevil]

Cheers nisskid

Also - my garage...unit complex and takes about 3 - 4 pt turn to get into my LUG - that would be pretty harsh in a 2 way yes?

[NYTSKY]

1.5 way is your friend.

[dori34]

would a shimmed diff chirp and sound like the diff is gonna break apart like a locker when doing low speed turns or a U turn??

do 1.5/2 ways have this problem as well or are they normal ?

Edited April 5, 2008 by whyte

[some_cs_student]

My stock 2way GTR diff shudders while doing slow speed, tight, turns, more when its cold then when its warmed up.

If you shim it tighter than its going to do it even more, as in every turn it will skip a little bit and groan...but if you avoid tight turns on the street then you don't have to worry about it as much .

[nisskid]

Cheers nisskid

Also - my garage...unit complex and takes about 3 - 4 pt turn to get into my LUG - that would be pretty harsh in a 2 way yes?

very, not as bad as a locked diff, but bad. it will also wear ur tyres out a fair bit. thing is, even with a 1.5way, when doing a 3pt turn ur probably going to need to be on the throttle anyway, so ull need to accelerate then take ur foot off the throttle and then turn while ur coasting.

[Duncan]

1 way is the best for reducing understeer under power if you can get one of those go for it.

I am using the standard 2 way gtr diff in the race car, it has been shimmed up so tight that I can hear it clunking around roundabouts at 50klm/h lol. goes brilliant on the track but there is a little understeer on turn in.

[BHDave]

1,1.5 or 2 way. They are all the same under acceleration. Unless your car is badly set up it won't push too much on acceleration (talking rwd here). I'm not saying you won't have the odd corner exit understeer moment post apex, but it's generally corrected with a slight lift. Same for exit oversteer. It comes down to set up and throttle control.

Deceleration is where the differences start. If you're braking in a straight line, they are all much the same. You may feel a slight bit of understeer with a 1.5 and 2 way when you lift off the brake and turn (again set up dependent). I find that if you run a bit of toe out on the front it's not an issue, alternately trail brake. Or if you brake in a straight line, lift and turn in and it wants to go straight, dab the brake again and watch it turn.

If you are braking in a curve with a 1.5 or 2 way, you probably won't notice, but people watching may comment that you are braking slightly sideways. wakefield turn 2 with shit rubber is a really good example if you go wide at the kink. Botch a down shift in that situation and around you go if you aren't ready to catch it.

If you get a 1.5 or 2 way and set up your car accordingly they will be both be fine. If you are worried about shuddering on 3 point turns you may want to stick with a viscous You definitely don't want a nismo 1.5 way (not the pro), tightest diff eva!

I wouldn't bother with shiming the stock viscous, it's a short term solution, and it may as well be locked when it is doing it's job.

Honestly, what ever you get, you will drive around it. I would suggest a 1.5 way, but i know guys who are consistently quicker than i am who have 2 ways. I only suggest 1.5 way as it is the happy middle ground and can do both track and drift work well enough, where as the 1 way is a rubbish drift diff and the 2 way is a bit too tight on decel for track work

[evil_weevil]

Dave,

Thanks for the reply mate, really appreciate it!

I'll certainly be looking into this more!!Im now not looking to do any more drift (cept for the SAU NSW Drift day in Oct?) Grip is where its at lol

Thanks mate!

[R32 TT]

You definitely don't want a nismo 1.5 way (not the pro), tightest diff eva!

Damn it!!! I just bought one of these!!... I should've got the TT huh?... oh well, hard core it is then....

[GTS4WD]

wow.. you guys are freaks!

how do you learn so much??

Tell me, i wanna learn more!

[bubba]

I <3 my Nismo GT Pro 2way. Noisy, clunky, tight, it's great - does exactly what I want it to do when I want to do it.

[NickR33]

anyone using the Cusco RS or MZ diffs? they are basically the same just the RS uses springs to dampen the chatter so a little more street friendly

[Beer Baron]

i have a nismo 2 way in the silvia. you are welcome to test it out chubbs. it's a farkin pig of a thing around the streets. it clunks like buggery and sounds like your whole car is about to fall apart! or alternatively it will chirp tyres. BUT on the track it's awesome. very predictable which is exactly what you want.

[Yawn]

The standard gtr diff is a 2 way? Im confused

[djr81]

OK. What I understand to be the case.

Standard rear GT-R diff is a two way. But there can often be little or no pre load on the plates. Copnsequence being it can bag up easilly &then become next to impossible to reign in.

The Nismo 1.5 way LSD Pro is a tight, clunky diff. Mine is. The 0.5 component appears to be a misnomer. The 0.5 way is square.

The difference between a TT LSD Pro & an Lsd Pro is the ramp angle. Less aggressive on the TT. But you cannot get a TT for a GT-R.

I realise that may not be too helpfull for your car, but it may enlighten someone.

Edited April 10, 2008 by djr81