View Full Version : Diff center for grip driving.

4th April 2009, 08:25 PM
Hey fellas,

What is main choice grip drivers go with diff center i heard that it is usually 1.5way? Is that correct?

Whats the best diff center for grip?

16th June 2009, 12:45 AM
It doesn't make that much difference in lap times aye... If you are a good racer and can put down consistent fast laps, there won't be any much wheel spin involved. The car will feel very different though. When i first wacked in my cusco 2way i was expecting it to give me massive advantage... it just wasn't there, sure the car felt much nicer to slide around on and off power... but laptimes are pretty much the same.

The biggest difference i felt between 1.5 and 2 way was when you car is already sliding, and you lift off the gas, with 2 way...car keeps sliding... with 1.5 way.. the car will try to get grip again...stopping the slide.

hope that helps...~!

16th June 2009, 12:48 AM
I tottaly disagree, maybe you didnt have any sudden tight corners but I kept on lighting up my inside wheel around the last 90 degree bend before the main straight on the winton race track

16th June 2009, 01:10 AM
I know what you mean, in very tight corners esp you've just clipped the curb with your inner rear. Last corner at Queensland raceway is just like that, not to mention its just before the main straight... where differences should show up big time. But it doesn't.

In normal racing situations (not riding on curbs) with high grip tyres, even tight corners can be handled nicely with open diff... you just have to use the throttle much more smoothly.

Just try it and time yourself... you'll be surprised how little difference it makes.

By no means am i saying open is faster or better.. but for track racing in a sprinter with semis... the difference is FA.

F1 cars of 70's/80's (forgot exact time period) tested and used open diffs because it was more efficient (LSD saps power)... and sometimes exceeded the traction benefits.

16th June 2009, 01:17 AM
Oh... forgot something really important... SETUP!!! Open diff setup should have keeping the inside rear contact patch intact as priority... ie. soft rear swaybars...

16th June 2009, 01:40 AM
interesting and I hear you. WHen I was at Winton I for example would follow someone and then lose some speed getting off the throttle to get traction back. I was also thinking that what if it was possible that someone could take a more agressive line on the inside and get the power down where I could not. But I am very unsure if such a situation like that be actually possible or if it really made as big a difference as you suggest. I wouldn't be suprised if in the end it didn't that much.

oh and I have found that too soft in the rear end causes heaps of problems too.

16th June 2009, 02:28 AM
The biggest difference I noticed is that with an lsd the car bites into corners. With an open wheeling diff you can tell exactly when it's going to loose traction but there's nothing you can do about it except to back off and then get on the power again when it's become all civilized. With an lsd it'll bite in and you can keep feeding it power, too much and it'll step out. It almost feels as though the car is turning in a lot harder with an lsd. Hard to explain more of a feeling if anything but you'll know what I'm talking about the moment you jump into an lsd equiped car

16th June 2009, 03:33 AM
If i have the choice... of course i'll choose a LSD car... especially on a AE86.
All i'm saying is don't laugh off a open diff car because they're just as fast...
Wheelspin (in racing) is not something you feel then back off and then on your way again... You anticipate it coming and you should control your throttle so that it never becomes an issue...

Having said that, if the track was wet/dirty/bumpy/really tight... basically where acceleration traction is a big issue... LSD definately makes a big difference...

16th June 2009, 04:30 PM
i can put up with open until you start throwing stuff like off camber roads and what not, like my hilux holds a bit more corner speed than my rolla did in its last livery, thats open and commercial tyres, compared to 2 way and higher end street tyres, two different cars i know, but you can be much more aggressive in places with an open diff, get some real floaty entries and direction changes that scrub off very little speed.

17th June 2009, 01:16 AM
So... to answer your question AE86R... If you can afford a LSD, just go the 2 way. Dont bother with the 1.5... its not going to give you any more speed. 2 way is more fun anyways. If you can't afford a LSD, just stay with open diff for the street, you're car will be just as quick in most situations. If you're track only and you're pov, then weld up the diff like dave has suggested... save you heaps of money..~!!

17th June 2009, 02:49 AM
I'd prefer an open diff for the track over a locker, unless it's drift that you're after. Neutral push understeer and then heavy oversteer make a welded diff pretty hard to drive smoothly and consistantly with. But again it depends on the track and conditions with regards as to how severe the diff will impact the car

17th June 2009, 10:44 AM
I'd prefer an open diff for the track over a locker

May I ask what track experience you have?

17th June 2009, 01:20 PM
i think the heavier the car the more it becomes an issue, 86's are just under that point

17th June 2009, 05:02 PM
May I ask what track experience you have?

Had both an open diff and a locker in my rx7. With the locker it was great for sliding but twitchy through corners, you couldn't push it as hard without it giving you trouble. With an open diff you can push and push and push and it builds up to the point of a loss of traction, and even then it's easily managable. With a locker there is no build up, it'll just step out and try rip your head off, which is good for drifting but not so good if you want to take a smooth approach to a corner.
The 2 way I have in my ae86 is brilliant though, you can feel it progressively get closer to stepping out, it's no where near as sudden as a locker, and when it finally does step out, it's very easy to manage and control. I've had my rx7, celica and ae86 on calder and winton and driven with open diff, locked diff and trd 2 way. I've only done drift events on the track but I've done plenty of hills runs and I know which diff allows the greatest and easiest control of the car.

17th June 2009, 08:18 PM
i have one thing to say

Detroit = win

edit: nothing wrong with the cheap weldy tho minimum requirement for fast laps

Andy San
12th July 2009, 07:32 PM
I gained about 3 seconds with my LSD, was getting wheelspin unless i waited until the car was fully straightened up without it, just grips and pulls now... much better. I think a locker would be favourable over an open diff if you can't justify spending the money to get the lsd

13th July 2009, 04:23 PM
ie. soft rear swaybars...

On this point, if you are going down the grip line, then i would start without a rear swaybar at all.

13th July 2009, 06:09 PM
I agree i have now gone to no rear swaybar from 18mm and its alot better. Highly recommend it, it alows the rear diff to move stopping the inside wheel leaving the road around tight corners which is the problem i had.