S15 Helical Vs Nismo GT 1.5way

[Topper]

Ok, i have been thinking about swaping my stock S15 Helical LSD for a Nismo GT 1.5way from another S15, as the guy who owns the car doesnt like it.

I've been toying with the idea for a while now (not even sure if the guy would still swap) as i'm a bit worried it might upset the car and put me off driving it. On the other hand, i would love to do a little more drifting in the S15

So just looking for the general opinions, i do mostly road mileage, the odd track and drift day in the nicer weather.... and away you go

 

[Yakozan]

Why not
I'f you can live with the noise I would go for it.
Remember that an aftermarket LSD would need more attention compared to the stock one. More frequent oil changes and stuff.

 

[Robbyp]

interested to hear what people say in this thread might go for one of these?
Yakozan how much noise is there of a 1.5 way?

 

[slammedmind]

got a 1.5 way in mine and its fun! Easy for daily driving you dont notice its there until you want to put it sideways. You get the usual clicking associated with lsd's but in time it isnt noticable

 

[irvs]

yea but thoes that dont know what the noise is, scares the poop outta them. think the back wheels are falling off.hehe.

 

[dcoghlan]

I would definatley reccommend it. I have the GT 1.5 way in my S15 and absolutley love it. It makes the car understeer a bit more and you can feel the car pushing/steering you from the rear when cornering, but I have adjusted my suspension/alignment to compensate. The car becomes so much more controllable and easier to hold in a slide

 

[Topper]

Ok so its good fun going sideways, but when you dont want to go sideways, how easy/difficult is it to keep the back end in check? - Right foot dependent?

 

[ichi-go]

Just dont go crazy and dump clutch then you'll be alright. My car came with aftermarket 2way but backend didn't kicked out that easily. Although mine is pretty stock power wise

 

[Topper]

So if i'm turning a corner at speed, change gear to fast the back end will fly out? - Sounds scary

 

[slammedmind]

i wouldnt say that, its very managable. Just use your head really, dont drop the boot on a tight wet corner if you get me?

 

[Topper]

I cant do that with the helical either, it seems to lock (or close to it) at slow speeds/rpm which sends it sideways untill the revs get up, then it straightens up and one wheel spins up faster than the other. Actually, thinking about it, its easy to get it sideways.

Ok, so, hammer down in 3rd coming out of a corner, going to go sideways? or grip like crazy

 

[Yakozan]

I cant do that with the helical either, it seems to lock (or close to it) at slow speeds/rpm which sends it sideways untill the revs get up, then it straightens up and one wheel spins up faster than the other. Actually, thinking about it, its easy to get it sideways.

Ok, so, hammer down in 3rd coming out of a corner, going to go sideways? or grip like crazy

Hmm. I think you need to look over your diff topper.
I have no problems getting sideways with mine. And if it straightens up, it's because of the acceleration and running out of revs in that gear. Not because of 1WD.

Only problem I've had with 1WD is donuts in 1st gear after a hard day at an airstrip. Shifted to second gear and problem was solved

 

[Topper]

The Helical Diff never locks fully, so shouldnt keep the car sideways.

When i say one wheels spins up faster, the other wheels is pushing the car forward, i dont just get one wheel drive.

As i said at low speed or low revs (or clutch kicking) the car will go sideways, i can make it go sideways by shifting the weight, but not simply by putting my foot down. If i plant my foot in a straight line it will squirm about a little to start with then just have one wheels smoking as the revs rise - Having said that, i've just described an open diff, yet it isnt and open diff.

This Video is from a while ago, before i had the oil changed, you can see that the passenger side wheels lights up and the drivers doesnt, yet i get the car sideways - 2.16 in.
http://media.putfile.com/knockers-vs-yello

This one is from the mornign session, was slightly more wet -
http://media.putfile.com/knockersmix2

 

[Yakozan]

Hmm. I see.
You get it sideways and when more throttle is added one wheel spins out and the car straightens itself.

I don't get that with my S15.
Getting sideways in first second and third when I tried drifting. No problems keeping it sideways either.

Anyone else?

 

[Nicely]

The Helical diff is crap for drifting for exactly the same reason its fantastic for road and track.

 

[Topper]

From what i've read of the helical diff, thats what its mean to do, it sends the torque to different wheels, which ever has the greater grip.... or something like that :wack:

 

[Yakozan]

From what i've read of the helical diff, thats what its mean to do, it sends the torque to different wheels, which ever has the greater grip.... or something like that :wack:

An LSD is supposed to lock the axle between the wheel so that one wheel with less grip doesn't take all the power and just spin freely.

On an open diff layout, it's easier for the wheel with less grip to spin and that wheel gets more power because it can rotate with less resistance.

The LSD sence that one wheel is spinning faster than the other and "locks" the axle forcing power to the other wheel.

From what I've heard the helical LSD only locks to an certain point, after that it can't take it anymore and thinks it's an open diff :wack:
It doesn'?t fully lock either, so one wheel would probobly be spinning faster than the other.

But looking at your vid, I would say that there is something else about your diff. You seem to loose all the power on one wheel at some times and spin the other.

I can only go with my experience from my diff. I can only say that it doesn't do that.

What do you guys say?
I've never had that problem like Topper shows in the first vid.

But I'm not really sure I have a stock diff either. It looked very stock last time I had a look at it though.
But another s15 owner, the new white one was kinda suprised that my rear wheels skipped when doing a sharp turn slowly.

I'll try to see what he thinks about his S15 diff.

 

[Topper]

My wheels skip on tight, off camber turns, but not when parking or anything.

nicely, you have done trackdays etc, when your back end comes out, do you back off or keep the hammer in?

 

[Nicely]

The one time the back end came out on me was going into Camp at Castle Combe last year. As I was in the middle of a pack at the time, I preferred to take the line over the grass than find out what happened on the track...

 

[Topper]

Has anyone who has the stock Helical, or remember driving it, know if what i am saying/showing is normal or not?

From reading what i have, including in this thread, i think this is how the Helical should behave.