understeer

[NotoriusCSR]

whats the best way to get rid of understeer? ive got tokico/eibachs and polybushings on right now.

 

[Mr Anonymous]

More neutral sway bar configuration.

Try looking at: http://www.panix.com/~awinbow/sho/suspension.html

 

[Xs SHO 1]

like a 24mm/26mm or 24mm/28mm combo?

<small>[ September 13, 2002, 03:22 PM: Message edited by: xssho1 ]</small>

 

[Mr Anonymous]

xssho1:
like a 24mm/26mm or 24mm/28mm combo?

I have the 24/26 setup on my '94 ATX now, and with the SFC's I'm pretty happy with it compared to stock, although I would still like a little less understeer and may try a 22mm FSB from a SLO wagon (if I can find one) and see what that does.

 

[NotoriusCSR]

im thinking 22/26, i do lots of spirited driving so should i go with 24 isntead of 22 and keep it on the understeer side? i dont pull 180s or anything, the occasional u-turn (which drive me crazy cause of the fact i use nearly 3 lanes of turning radius...) i do do a decent amount of high-speed driving on paved surfaces that arent totally straight so would slight understeer be better or is 22/26 just about perfect?

 

[mopower]

On the track I have been expiramenting with higher tire pressure in the rears. I plan to add konis so i could dial in the stiffness back there. Also make sure that you havent added a front strut tower bar.

 

[NotoriusCSR]

nope, no front STB, i think the firewall kinda acts like one doesnt it?

how much would a rear STB help?

 

[noSHO]

Here are my thoughts...

I'm running 24/28 right now. Polys and HD endlinks in the back, Intrax, Koni's, and SFCs. The car has a tendency to understeer a little when pushed ******* the street, like trying whip around a right turn to catch some ricer's attention or something (we all do it, don't deny it). If you do most of your driving on the street, or AutoXing/street situational driving is your thing, I would say either 22/28 or 21/26 would be better. HOWEVER, I have found that for long sweeping corners, like highway onramps, flowing country roads, or the like, my swaybar combo is near ideal. I still get a LITTLE understeer (but that's what the quaife is for, hehe), but I think I'm going to try different settings with the Konis, and maybe a set of wider wheels before I swap out my front swaybar. I'd rather do road racing than AutoXing, so I set my car up accordingly. I think where my car sets and plants to the pavement a car with a 22/28 or 21/26 setup would have a handful keeping the ass of the car steady. Again, the quaife helps, but I had plenty of experience beforehand anyway. IMO, STBs don't give in return what you pay for them.

 

[NotoriusCSR]

well in colorado the roads are either straight, or long and have sweeping curves in them, tight corners are usually only found in peoples driveways. so ud recommend 24/28s?

and will adding SFCs help at all?

 

[noSHO]

NotoriusCSR:
well in colorado the roads are either straight, or long and have sweeping curves in them, tight corners are usually only found in peoples driveways. so ud recommend 24/28s?

I'd recommend that combo, yes. I'm real happy with it, and it will work well for those long sweeping turns.

and will adding SFCs help at all?

Yes, definitely.

 

[ThrillSHO]

I auto-x my SHO twice a month and do about 2 track events a year and have had 4 different bars on it. The current 24/26 setup is pretty good, but still understeers some. The tighter and slower the corner the worse the understeer. On the track it is barely noticable.

I'm playing with a couple of modifications:
1. Solid rear endlinks with hemi-joints. This will have the same effect as stiffening the rear bar.
2. Adjustable front 21mm bar. I have a 21 and plan to weld onto the ends to make it longer with a choice of endlink holes. This will have the same effect as softening the front bar.

Then I should be able to tune for auto-x or track.

 

[Mike Kopstain]

I have a 24/26mm setup with Tokico's, a front strut tower brace, and wider, lower profile tires, and even though the car is a **** of a lot tighter, if I whip it around a turn it's still going to slide. I still haven't found a SHOcago member that can out handle me though.

 

[AutoXSHO]

I've been autocrossing the 21/26 combo for some time, and I think it's pretty close to ideal for a car with an open diff. Bottom line, you're going to get too much corner exit wheelspin with a bigger front bar, and autocrossing is all about corner exit speed.

I got marginally better times running no front bar and a rear 26mm bar, but the car was a handful in transient maneuvers. Man, it would really lay down the power without spinning the inside tire though.

A 23/26 combo (if it existed) would be awesome for slaloms, and the 21/26 is pretty good for overall MTX autocrossing - the car is very sensitive to tire pressure. For the nose-heavier ATX, the 24/26 combo is probably pretty damned good, too.

My $.02.

John

 

[DeaconBlue]

I agree with John V. I have driven his car and he has driven mine. The 20.6mm/26mm combo for the MTX with open differential is very responsive, with a touch of oversteer just for fun. I am going to try the 22mm/26mm combo to see if it is more balanced on the highway and for open track (not autocross) use. The ATX's are more nose heavy and really need the heavy front bar of the 24mm/26mm combo. Of course there are now even heavier aftermarket bars out there that you can try, but you can also go too heavy with sway bars combos as well and have other problems.

 

[srfdude]

Spring rates will affect the response, as well. In my racing days there weren't such a good variety of sway bars, and we had to play more with the springs. My '90, with the HD springs and 24/26 bars, handles a lot tighter than my '95 ATX, in fact its too stiff in the front, spinning the front tire at every opportunity. The ATX has SLO springs and 22/21 bars and is a pig. I guess the point of this post is to say that someone else's experience may not be what yours will be if you don't have the same spring/shock setup.
Mike

 

[SHODWN]

21/26 ? John your crazy. Understeer is caused in our cars but a thin front swaybar and a fatter back one. your front end is twisting and the back is working 4 times as hard trying to keep it flat. Thus this causes your pushing in cornners
and when it catches with a stiff back end will pick a tire off the ground (like your pic shows) im sorry but 4 tires on the ground will always be better then 3. take the 21 and use it to hang parts from when your painting stuff.

 

[noSHO]

SHODWN:
21/26 ? John your crazy. Understeer is caused in our cars but a thin front swaybar and a fatter back one. your front end is twisting and the back is working 4 times as hard trying to keep it flat. Thus this causes your pushing in cornners
and when it catches with a stiff back end will pick a tire off the ground (like your pic shows) im sorry but 4 tires on the ground will always be better then 3. take the 21 and use it to hang parts from when your painting stuff.

So then why didn't my 24/23 combo handle better than my 24/28? I lost a LOT of understeer when I put in a bigger rear bar. The understeer is caused by having a front bar that is too stiff, causing the inside wheel to spin under acceleration and the car to push. In non-acceleration situations, the tires don't have enough grip to keep the stiff front end planted in comparison to the lighter rear bar. At least that's how it was explained to me...

<small>[ September 22, 2002, 10:02 PM: Message edited by: noSHO ]</small>

 

[Mike Kopstain]

John, if one autocross event is Slalom, dodge the cone , etc, how do you choose what bar to use? Do you just go with the one that you think will be the best in all the different competitions or do you change between events? Is there possibly a way to dial in a stiffer front end via the sway bar? Maybe an adjustable mount on the endlinks?

 

[srfdude]

SHODWN:
21/26 ? John your crazy. Understeer is caused in our cars but a thin front swaybar and a fatter back one. your front end is twisting and the back is working 4 times as hard trying to keep it flat. .

Kirk, this is exactly right, the front twists enough to keep both wheels planted. The back will unload one wheel if bar/spring combo is stiff enough, leading to an oversteer condition. A FWD car, if taken to extremes will have a snap condition, very dangerous at high speed on the street.
Mike

 

[ShoGuy93]

So would the 24/26 set up be the best set up for the street and high way on/off ramps? thumbs_u