Suspensions and stearing setups

[Abe]

Hello:

I have a problem with my AE, it is very very very understerer.... with or without gas is the same.... have a crazy underster until broke the grip and change to a heavy overster.... This car not is my first fr, I had an S13 with an vlsd, and I drived other cars.... other FR drivers when drive my AE think the same... a lot of underster.. and very difficult to control the oversteer...

I have:
-Cusco LSD 1,5 vias
-Coilovers K-sport 7kg/5kg F/R
-Bushings Protane
-195/60/14" Toyo Proxes CF 30psi F/R
-2º cambers, RCA/ Castor 3.50/ toe= I don´t know

where is the problem? I want a well balance car, neutral or a bit underster, but only a bit.

I read it in other forum:

Zax: I used OEM front swaybar with prothane bushings. In the rear I clamped 2 OEM swaybars and worked great for me. Car was more prone to oversteer, maybe bit too much. And my ae86 never understeered, never. Setup was 8/6 springs, with coilovers, RCA. 3° camber, max castor and bit toe out.


86jay: I run a whiteline at the back and a standard at the front. The car starts to slide real easy but still leans over a fair bit in the turns (I run 6kg 6kg springs). I might try Largus ones if I ever get any spare cash. Jay ________________________________________________________

I,m thinking in change my spring rates to 5kg/4kg F/R more equal (and more soft, because the car is a bit stiffer for my usuals roads) and put a rear sway bar around 50% more stiffer than OEM... what do you think?

Regards & thanks

[Abe]

ah... sorry, my car not is a driftcar... its for tougue whit my friends and for trackdays... but I practice drift few times.


Regards

[Mux213]

Hey Abe,

My car had a tendacy to understeer alot aswell, I think hachi's generally have a tendacy to understeer for some reason anyways.

Right now in my current setup I do think its more neutral or biassed towards oversteer but I do think alot has to do with my driving having improved alot aswell.

One thing that did improve my cars handling ALOT was tires. Then again you do mention you have Toyo Proxes, I would think those would give plenty of grip and not lead to understeer behaviour. My car improved loads when I went from Yokohama A539 to Bridgestone RE720's. I think for my car, that was one of the major causes of understeer.

Also for me alot changed for the better when I finally got my 6.25kg/4.5kg suspention setup, but you mention 7kg/5kg on yours and that really sounds like a good setup so I can't imagine that being your problem either.

[Abe]

ok, my car understeer so much.... whit this spring rates
I have a cusco type rs I think this is 80% acelerate 40% deacelerate, this very agresive... and make the car very understear...

Regards

[Mux213]

Abe,

The Cusco should be fine, it should have a positive effect on grip, not a negative effect, so I really doubt this is your problem.

Besides, with understeer you have a grip problem on your front tires so I'm more thinking suspension/tire setup anyways (though I'm no expert). Still your suspension doesn't sound bad at all, can't really imagine why it would be understeering so much, would have to see the car drive/experience it driving...

Going 5/4 on the suspension should give a much more oversteer ride but I would normally think that would be going much more to a drift biassed setup as it would more result in the back end getting too loose. Same really with the double swaybars, that really is something you'd want to do if you want a drift car, not a trackday car.

With my car I drove around on 6.25/2 for a long while. With the yokohama's this was a very understeering ride. I always had grip problems but in theory this setup should give massive grip on all 4 tires and be an ideal track setup.
When I switched to Bridgestone RE720 tires I actually found out my car really turned into a gripper and my problem had been the tires all along. I had no understeering problems with this setup, but also it was very hard for the car to get it to oversteer, you really had to do something stupid to get it t o oversteer (and I did once or twice ).
The biggest problem I had with this setup is that the difference in springs (atleast I think that was the cause) made the rear and front of the car behave so differently the car never felt very stable.

I'm no driving with the 6.25/4.5 setup which has made it a tad bit more biassed towards oversteering which is a bit easier to initiate now (allthough it still grips just fine) but what has improved much more is the stability and the controllability of the car on the edge of grip.

Anyways, point is, I can't really believe your suspension setup itself is the problem, it sounds like you have what should work.

What sort of shocks are you running? Do you have adjustable shocks? If so you may want to try playing around with the settings on those. If you have your front shocks very stiff, and your rears very weak, you're bound to get a car that tends to understeer aswell, you may want to try and stiffen the rear shocks up, or weaken the front shocks, and see what that does to the handling of the car..

[Abe]

I have coilovers Ksport adjustables in 36 point, and have the rear more stiffers than front but not is enough.

When I buyed my car, It had put soft bisltein in the front and koni sport stiffer in the rear and feels good with the springs OEM, whit less grip than now but more neutral.

Cusco LSD is a good LSD, of course, I´m very happy with this... but is very agressive and make the car very very understeer...but works very well, Other friend have a SW20 (toyota mr2 turbo) and put other cusco and he feel the same... understeer but her car is more balance of mine, and grip very well.

Toyo Proxes, can be the problem.. yes... but no work so bad... my next tires will be Advan a048 or Toyo R888.....but I think that my spring rates are very good for a open diff or OEM lsd but no for a Hevy LSD....

Yesterday at night I search in Internet and Cusco rear sway bar is a 54% more stiffer than OEM sway bar.... If zax with 8/6 and 100% more stiffer rear sway bar.... her car ever oversteer a bit ...

86jay said he goes whit 6/6 and more stiffers rear shocks to have the car balanced for trackdays.... I can go for this set up but I think the car is very stiffer rear, and the rear axel jump very easy.

I suposse whit 6/5 or 5/4 and 56% more stiffer rear sway bar the car will feels neutral...

KSport have a suport very good is more cheaper buy 3 sets of springs than change my tires.

Other cuestion:

which set up in cambers/caster/ etc have in yours car?
and psi in tires?


Regards

[PazzaAE86]

Its seat time. The LSD will push the nose of the car out constantly, unless you learn how to turn the car properly. I would get on the track and get used to the car, making it drive how you want it.. And stick more PSI in the rear tyres to add some easy to control oversteer.

[Abe]

PazzaAE86 Wrote:Its seat time. The LSD will push the nose of the car out constantly, unless you learn how to turn the car properly. I would get on the track and get used to the car, making it drive how you want it.. And stick more PSI in the rear tyres to add some easy to control oversteer.

yes of course its time to make seatings and to learn... I have other fr, all cars are diferent and need a diferent type of drive.... but at this moment my car is out of control in a crazy understeer... Not is only my feel, more fr drivers said me the same... and one very experience fr driver, and very good drifter said me the same...

Add to my list check my PSI in tyres...

Regards

[Mux213]

Abe,

camber/caster for me is still unknown, bone stock.. still have to get her alligned but wont do this until I get my struts shortened and RCAs installed...

Well, best thing to do is just to experiment I guess, indeed, buy some other springs for the rear or a stiffer anti rollbar and see what it does...

Have to agree with Paz though, might just need loads of track time, its amazing what difference a cars handling can become as you improve as a driver...

[Red]

"Its seat time. The LSD will push the nose of the car out constantly, unless you learn how to turn the car properly."
Hmmm...Well, bone stock and street driving only, I can only say I have never noticed the stock LSD pushing the nose out. The car tracks damn nicely, never wander toward the outside of a curve.

But from everything I have read, the car is very close to neutral and the difference between oversteer and understeer can come from the front end alignment and the tire pressure alone. The printed "acceptable range" for the front end alignment is very wide. Over the years, I stuck with one front end shop for a long time and even "within spec" have noticed what I'd call a huge change in steering at speed.

Then there are also the wheels, if you are using aftermarket wheels with a non-spec offset...that's going to make cornering change too. I'm not saying the car can't be improved from stock--only that stock is a damned good starting point, and it is easier to make it worse, than better.