29 replies to this topic

[DOUGMO]

you would be better off leaving in the castor, id say your toe setting at the time made it twitchy, as castor wont do that.

or the fact that it actually turns in better

 

do you have the bar on the firmest setting?

[LumpyVR4]

Do you think the throttle off oversteer in the wet will be ok?
It would put the spooks up me the first time it swaps ends in the wet..
Just dont back off eh?

 

Basically the more throttle I have, starting from off through trailing to on, the more I can fee the rear wanting to overtake the front.

 

Was wet this morning. The over steer was coming in at slower speed as you'd expect, but it wasn't diabolical knowing how the car reacts to steering input.

 

you would be better off leaving in the castor, id say your toe setting at the time made it twitchy, as castor wont do that.

or the fact that it actually turns in better

 

do you have the bar on the firmest setting?

 

The bar is on the end holes so, correct me if I'm wrong, the softest settings.

 

I was thinking about taking a little pre-load out of the rear springs to let the tail roll a little more than it does now.

Edited by LumpyVR4, 30 November 2014 - 07:27 PM.

[DOUGMO]

if the oversteer is happening under power and not off throttle, its not related to castor or the rear sway bar imo

[LumpyVR4]

After testing at a higher entry speed it does happen off the throttle, but throttle input accentuates it. It's also the only change I have made taking the car from under steering at its limit in a constant radius constant speed turn to easy over steer with on boost throttle or tug of the wheel mid corner.

[DOUGMO]

what tyres are you running?

[jack be nimble]

Im not having a go at you lumpy, but if its tail happy under power, then the day you are going a bit faster than tha average nobber, and something makes you get off the gas,, it will snap into oversteer.
The benefit to this is no front enders, you are going passenger door first....
There is a great julian edgar article...let me find it.

Caster will help it a bit.

[jack be nimble]

http://www.autospeed...le.html?&A=2359

Here, julian is a good writer. He is the guy behind the zoom cyborg in the mid 90s

[LumpyVR4]

Tires are Kumho ecsta le sport ku39 225/35/18. I should also mention the rear diff is a 4 bolt LSD that has just been rebuilt.

 

I feel I should note that I don't take every corner at the limit of adhesion. I've just been using some corners I know well to learn how the car now behaves when it is at the limit.

 

Lifted from the article:

Note that a front-wheel drive with an over-stiff rear sway bar (or more correctly, too high a total rear roll stiffness) will feel great up to 8/10ths – turn-in will be sharp and the car will sit flat. But go that extra step and you can be bitten.

 

This is exactly how I think the car will react when you go past the limit. It will hold on and then let go violently putting you backwards into whatever is in your path. Ideally I'd really like to get it on a skid pan to find out.

 

 

 

Got time on my hands today so have been researching and found this...

 

http://www.whiteline..._Galant_VR4.pdf

 

My plan at the moment is to get the front bar links and bushes in, drop the back spring pre-load and maybe add a little front. If It still feels like it always wants to swap ends I can get a 23mm front bar from Ultra Racing. Then I'll drop all the spring pre-loads, have a nice cooshy ride, and let the bars do the work in the corners. But then the whole car could be too stiff and compromise wet weather handling. So perhaps just getting a 23mm rear bar instead could be the go?

Edited by LumpyVR4, 02 December 2014 - 08:06 AM.

[LumpyVR4]

Update: I pulled out the rear pre-load I had added to stiffen up the back before adding the bar. The rear is still tight, but it feels like you'd have to be much more stupid for the car to kill you, which I'm sure it would still do if you were.

 

Edit: The new Nolathane bar links and bushes on the front have helped more, but in an emergency maneuver at speed the car would still swap ends on you.

 

In hind sight I got a bit carried away about getting a good deal on the rear bar and didn't think about its size compared to the stock front one, just that I was getting it cheap. So tomorrow I'm ordering a 23mm front bar. A 23mm rear bar would have been the way to go at the start. Oh well. Now I know a lot more about sway bar sizing.

Edited by LumpyVR4, 07 December 2014 - 05:24 AM.

[LumpyVR4]

Finally this bit of the car is done (well for now). I've got the 24mm bar in the front to compliment the 26mm rear. I've reset my cheater spring and caster settings to where they should be, replaced the tyres that I killed prematurely with all my suspension shenanigans, and have had a full alignment done.

 

She sits pretty damn flat and neutral in corners now, and I think I'm going to need something like late EVO seats if I ever want to find the limits of her cornering abilities.

 

The only thing I need to do at a later date to wrap us the chassis/ handling thing completely is install triangle frame bars to tie the cabin to the front suspension and get rid of the flex at the fire wall.