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rjrutzky
01-19-2005, 03:26 PM
Last track day I wore the insides of my front tires down to the cord. On exiting corners, My inside tire would just spin (02WRX no front lsd). Would a anti-lift kit help this? Susp set up is, tein flex, rear strut bar, frt/rear sway bar, 1.5 deg camber front, .5 deg camb rear, kumho mx tires. It is very neutral (what I like) going into the corners, but on exit, just wants to push and spin. I have to baby it to keep it from spinning. Also, if alk will help, how noisy are they? I have enough clunks already. Thanks all.

DrBiggly
01-19-2005, 03:55 PM
Nothing helps this really; it's a common phenomenon. Only an LSD would fix this on a WRX as far as I know. It's quite common in autox as well. :)

kwak
01-19-2005, 04:07 PM
A couple of things you don't specify:

What is your front ride height? According to Whiteline if the front ride height is dropped more than 35mm (1.4 inches) then the roll center drops below ground level. This creates MORE body roll which makes camber gain issues worse, the inside tire goes way negative. The Tein Flex recommended drop is 50mm. That's too much.
What are your front and rear bar sizes?
What is your front toe setting?

There is an ALK FAQ (http://forums.nasioc.com/forums/showthread.php?t=682924). Whiteline uses a rubber bushing instead of a solid bushing like Perrin. And Whiteline does offer a Comfort version of the bushing. A simplification of what it does, during accel the "anti-lift" built into the stock suspension causes a partial binding of the front suspension. The ALK reduces the binding allowing the springs to work better which allows the tires to have better contact with the road which improves grip.

rjrutzky
01-19-2005, 04:08 PM
That's what I thought. Some one give me a 6 spd pulease. Or RA gears and a front lsd. I can't believe they built our tranny with no front lsd--sux!

supermarkus
01-19-2005, 04:08 PM
cuts costs.

kwak
01-19-2005, 04:57 PM
Nothing helps this really It helps to at least address the known issues of the car to reduce setup related issues. And driver related issues ;) if any. Then you have to live with the rest of it.

PaulC
01-19-2005, 05:01 PM
Modify your driving style so you're almost done turning when you get on the power.

That's the simplest way to fix it, IMO. There's no easy way around the power-on push in your car, you drive around it or put in an L$D.

ebeck
01-19-2005, 05:07 PM
Yep. I hear you. I tried everything. What fixed it was the JDM 6mt and JDM R180. Now the throtttle can be used to rotate the car mid corner. When I was getting used to it the car would oversteer. I have to back off the rear bias a little suspension. Have not does it yet as I kinda like it now. Just have to be carfull with the throttle under boost in sweepers.

Prior to that fix, PaulC's recomendatoin was right on. However it still was horrible.

rjrutzky
01-19-2005, 05:23 PM
A couple of things you don't specify:
[list]
What is your front ride height?

1.5 inch drop front, about 1.0 rear WRX wagon. I've read the alk faq. Just says they are noisy and help turn in (in a nut shell). Doesn't specify how much noise and if it will help my inside tire smokin' problem.

Bottom line my car goes slow exiting tight stuff and I need to drive it that way. 6mt swap is just to expensive for me.

Does anyone actually have an alk installed? Does it affect the specific issues I am having? Expensive item for trial and error. All my searches have come up with "yeah works great" to "makes a loud clunk" to "mine makes no noise"

DrBiggly
01-19-2005, 05:44 PM
All of the National autox'ers do it that cannot have a front LSD. If one is pushing their car a bit, I don't see how to cure it other than with an LSD.

I don't think his setup is bad kwak. I'm sure he could do a few things to minimize it, but at the expense of what? Overall grip? :)

kwak
01-19-2005, 06:49 PM
DrBiggly, just checking to make sure he wasn't doing something in the setup to PROMOTE camber gain issues.
at the expense of what? Overall grip? Never! :D

DrBiggly
01-19-2005, 07:17 PM
DrBiggly, just checking to make sure he wasn't doing something in the setup to PROMOTE camber gain issues.
Never! :D
Good! :D

CBRDSpeedfactory
01-19-2005, 07:26 PM
how are u driving??

first of all...

second of all, there are a few things to try....
front bar is one thing...... try soft and harder... if u can...bars have an interesting effect,...they dont always do what u think.....

we used to use them on a stiffer setting just to get a more positive turn in, other times, we'd lose all front grip...

its a combination of everything....

do you feel alot of weight transfer when you get on the gas?.... could u use a higher gear?

do this....talk us through how the car feels when you...
a. brake.
b. turn-in (are u still o nthe brakes? are you coasting? or are you picking up throttle)
c. car's behavior from ur initial turn-in into the apex.... (and what you are doing)
d. car's behavior mid-corner, and starting to track out..
e. car's behavior on exit..

those key details will help for a lot more input

chad b

DrBiggly
01-19-2005, 08:36 PM
ur shift key is broken

kwak
01-19-2005, 09:04 PM
at the expense of what? Overall grip?Never! :D I'll take that back. Yes I would if I got faster lap times. :p

DrBiggly
01-19-2005, 09:27 PM
I'll take that back. Yes I would if I got faster lap times. :p
To an extent that does work in autox...but only if you can deal with a really twitchy car. :devil:

rjrutzky
01-19-2005, 10:30 PM
do this....talk us through how the car feels when you...
a. brake.
Car doesn't dive much at all, but I'm not late braking. I could go in alot deeper, but braking early feels good to me and the car is settled at turn in.

b. turn-in (are u still o nthe brakes? are you coasting? or are you picking up throttle)
No brakes at turn in, unless a squirrley vette holds me up :furious:

c. car's behavior from ur initial turn-in into the apex.... (and what you are doing)
To be honest I could be smoother with the wheel, I sometimes yank, but I'm getting better.

d. car's behavior mid-corner, and starting to track out..
Very neutral. If anything a four wheel drift with 70% on the outside wheels

e. car's behavior on exit..
spin, spin spin (second gear turns)

I have a vf22 and hit 18psi at roughly 4000, so if I take a 2nd gear turn in 3rd, I'm goin nowhere. Part of the problem here as the vf22 hits real hard at 4000.

Thanks everyone for all of the advice, and keep it coming. But to get back to my original question: Will an ALK alleviate some of this problem, compound the problem, c. no change. Thanks all

WillysPU
01-19-2005, 10:31 PM
When you say "track day" are you autocrossing or road racing?

rjrutzky
01-19-2005, 10:32 PM
road race

CBRDSpeedfactory
01-19-2005, 10:55 PM
a few things...

by your level of feedback, it sounds like you are.... kind of getting more serious... but just kind of having fun??? is that right....

see im a hardcore racer...so im always just like... i need this i need that....

have you tried a heel-toe technique as you are coming into the apex, try a higher gear...3rd for example...

obviously you are done your downshifting... you may want to switch your left foot to the brake...in case you need to drag...and what you can do is...

as youre entering the apex....try to apply throttle as if you are heel toe-ing but with the purpose of spooling up ur turbo....u may find its just enough to bring ur boost up where u need it....

maybe it wont work at all....otherwise...what engine management do you have?? with something like a utec...i would look at running a bit more timing and have you turbo come on boost later more progressive, that way you are using ur smoother normally aspirated power as you apply the thottle...

or tune to get a little spool up sooner but more linear.....

i drove a 2.0 liter 560hp 1400lb. turbocharged engine for 2 years...talk about a kick in the ass.....

i had to adapt to basically not ringing its neck, but torque-ing it.... you learn to stab the throttle as you are coming into the apex, to give the turbo a quick whirl, then back off a little and then power back on at the apex....

anyway...email me if u want more details...

chad b

pio!pio!
01-19-2005, 11:01 PM
1400lb engine!!! hahah j/k

CBRDSpeedfactory
01-19-2005, 11:18 PM
wait that wouldnt be fast!!

it was a 1400 lbs carbon chassis lmp car...with 560 hp

lol

got me

ahh it hurt

chad b

WillysPU
01-19-2005, 11:18 PM
So exiting tight turns you are lifting the inside front tire and pushing through the turn?

Pushing (understeer) can come from a front suspension that is too stiff or a rear that is too soft.

Sideways front lift under power can come from too much sway bar F&R, not having enough suspension travel or having all suspension too stiff.

My guess is:
Your car may be lowered too much so you do not have enough front suspension travel.
Your front and or rear sway bar may be too big or set too high.
Your front springs and shocks maybe set too stiff.

So you would need to:

Raise your ride hight a bit to get more suspension travel.
Soften the front suspension by running softer springs,
reduce the shock rates,
lower the pressure in the front tires,
run less front sway bar.

and or

Increase your rear sway bar
Increase the rear tire pressure
Stiffer rear springs
increase the rate on the rear shocks

Get the idea?

My setup is no too different from yours, check post #6 for my settings:
http://forums.nasioc.com/forums/showthread.php?t=570909

I get awesome grip on the track, so much so that I worry I will snap an axle accelerating out of tight corners. Remember to let the car track out to the far edge of the track on exit . . .don't try to fight and keep it in tight.

Good luck!

Jim

kwak
01-20-2005, 01:21 AM
To follow up on Jim's "track out" comment. Ideally you should be able to go to full throttle when you see the exit (the straight part of the track) and be unwinding the steering wheel at the same time.

To fill you in on the banter DrBiggly and I were exchanging, on the track it is very important for a car with any sort of hp to be able to go to full throttle exiting a turn without having corner exit understeer. Corner exit understeer will kill your straight line speed and lap times. In your case it also kills the tires.

Cording the inside edge of your tire is an indication that your inside tire has too much negative camber when the car is fully loaded in a turn. Your static camber of -1.5 degrees is NOT causing this. You should be able to run a lot more negative camber with no problem. Something else is causing this.

Important: If your front coilovers are lowered too much you NEED to raise them up. Too low causes excessive negative camber on the inside front tire in a turn and you will cord the inside edge. The default settings of your Tein Flex coilovers lower the front too much. Raise the front coilovers from the "slammed look" setting of a 2.0 inch drop up to the performance height of 1.3 inch of drop (or a little higher). These measurement are based on stock ride height.

The ALK will not hurt and should help. But I think you need to fix the above first. Then get the ALK (it fixes a known problem). Then look at Jim's tuning tips.