Help with grip setup

[spanishricer]

Well here's the deal. This is my daily driver/weekend warrior car. I take it to both the drag strip and the backroad twisties. I thought that my current setup would be adequate for both, but I'm obviously lacking in some areas. Here are my current suspension mods...

KTS coilovers
SPL front tension rods
Tein tie rods
Cusco RUCA's
SPL rear toe arms
Tanabe subframe spacers
Cusco front strut bar
S15 HLSD
245 width front tires, 275 width rears
Camber set at 2.5 front, 1.5 rear, with toe zeroed out.

There are 3 things I'm looking to eliminate.

1) Bump steer. I'm probably going to pick up a set of SPL adjustable tie rod ends to help cure some pretty wicked bump steer.

2) Understeer. Largely due to the 240's natural urge to understeer and not being helped by my tire size selection. Was thinking maybe a bigger rear sway bar?

3) Tire skipping and lift. Right now my car skips over imperfections in the road. Skips bad. I think this is due to an excess of preload on my coilovers, because I've never heard of anyone else with the KTS units, or any other 8k/6k setup, having this problem with 0 preload.

Am I on the right track? Are there any other suspension mods that will help me in my goal to have a streetable corner carver? I'm not a suspension guru and would appreciate any input you guys can share with me.

[thundering02]

275's and an LSD will help any car understeer.... Sway bar not so much with the bump steer....and how bad is the hopping? could be that your just running a little soft in the shocks.

[DJPimpFlex]

tires........done....... Seriously, I dont know why anyone stagers there set-up.

[spanishricer]

The hopping or skipping is very bad. If I hit even a little bump in the road when going around the corner, the rear end pops up and well...it's not fun. Shock settings are 7 clicks up front and 5 in the rear. I was thinking that maybe it's just too stiff?

[irax]

just slapping on the SPL tie rod ends wont help unless you get the SPL lower controll arms, you have to actualy take mesurments and make sure you setup a proper roll center, close to stock... that will help out alot with the bump steer. another thing is that tire sizes you chose inst that bad but 275 is waaay too big if your less then 350hp. you can help this if you dont want to get rid of your tires is by seting up a proper race temp pressure ballance in the front and the rear... you might want to get a bigger sway bar in the rear but you maybe able to just get a rear strut tower bar and dail in the oversteer where its alittle more controllable... you might also want to remove all the old viscous bushings in the rear and go with a solid or polyurithane bushing that will help with hopping during launch you might want to soften in rear abit too...

[spanishricer]

tires........done....... Seriously, I dont know why anyone stagers there set-up.

Yeah well, 400ft/lb of torque ownz me :doh: No choice but to play either large rubber or run drag radials daily. I drive 70 miles to work and back daily, so drag radials are out of the question. I can only try to minimize the tire size difference from front to rear. At least I'm not running 225's in the front with 275's in the rear...dear god :keke:

irax, you've given me some more options to consider, thank you. I wasn't aware that I would also need the SPL adjustable front lower control arms in conjunction with the tie rod ends to accurately eliminate bump steer. Learn something new everyday :bigok:

So you think I might be able to get by with just a rear strut tower bar instead of a bigger rear sway bar? Hmmm...more to consider.

[irax]

what kind of power you puting out?

yeah im sorry i made an ass of my self because I run 255in the rear and 245in the front with a stock ka and I have no problem loosing or maintaining grip an I assumed you were doing something close to that....

[BOROSUN]

git rid of the preload.

then git some largus sway bars, see how it feels.

[OptionZero]

Drag and track (the real kind, not just a straight) aren't really compatible.

You want a little toe in for stability in rear and a little tow out for turning in front.

You want ZERO camber for drag, but you want some for turn in.

400lbs/ft sounds great, but i'd love to see a power curve...because usually 350rwhp is pretty darn fast for most people on most tracks. Sacrificing peak power for more area under the curve would make you faster...but again, this is speculation on my part regarding your circumstances.

again, trying to mix drag and track ...seems kinda stupid because the goals in each often conflict

[ISTOTOSAO]

#1 and #3 Raise the car!