LTFA182

I'm sure most of us have seen the progress sway bars and eibach anti-roll kit. Now progress sways are 22mm both front and rear. The eibach are 32mm in the front 19 in the back. My 07 SI stock bars are 17mm. My question is which one do I go for? Will the eibachs feel more balanced because of the weight difference in the front and back? Or is it better just to get equal size bars? Why would they sell the kit if it didn't work right?

robbclark1

iTrader: (8)

What is the intended purpose of your vehicle?

The FAQ has info on what sway bars do.
Larger front = more understeer
Larger rear = more oversteer
(and any combo above).

Each car is different, but I would shy away from the Eibach because of very large 32mm bar. I would leave your stock front bar at 17mm and get a larger rear, which should make the car feel more neutral. But you have to read what others have done with the car, especially the autoxers.

gearbox

iTrader: (95)

for daily driving, rsx 19mm sway bar does just fine. throw in some ES bushings for it and better endlinks and call it a day. leave the front alone.

sdaidoji

iTrader: (1)

Got the eibachs 3 years ago. felt good in streets, but when i started autoXiing, the understeer was really bad. left foot braking, slowing down, etc nothing did seeem to cure the problem. one day, simply softened front shocks all the way (KYB AGX), got a second in a 65 course... Since then, front stock sways are back, front shocks at 3 (max 4). Rear sways still eibach, hard setting and shocks at 4 (edit - was confusing...), front to rear tire pressures are at 6PSI higher in the rears. Car have the eibach lowering springs, though. might behave better if stock springs.
In other words, if you want a car with small roll, get front and rear.
If your objective is grip and fast (edit... what's fat times anyway...) times, keep front stock and enjoy the grippier but higher front roll. (edit again... fingers are not as fast as the thoughts...)

robbclark1

iTrader: (8)

You are doing everything the wrong way. You want to SOFTEN the front and stiffen the rear. Front tires should be HARDER than rear tires. Front shocks should be SOFTER than rear tires.

sdaidoji

iTrader: (1)

? Yeah, that's what i did...
? Isn't it the other way?
? Shocks or tires?

robbclark1

iTrader: (8)

Sorry I meant shocks.

No, softening the front makes the turn in sloppy, but makes the turn out faster. Slow in, fast out. Anti roll bars increase the spring rate when installed, therefore, you want a SMALL front sway and a LARGE rear sway. At least enough to make the car oversteer while still being controllable.

Overinflated front tires will keep the sidewall from collapsing, while allowing the rear end to slip out.

Also, you need to get a good alignment. As much camber up front, and only .5-.75 rear.

And you did a ninja edit on your post to change some things lol.

sdaidoji

iTrader: (1)

First things first: Bwahahaha!

sdaidoji

iTrader: (1)

Agree completely, that's the reason i went back to the front stock sway
That's the part i am still confused, of course it depends on the pressure i am using - currently tires i have are the Potenza RE760, equipped only with fabric reinforce in the sidewall, previous ones were the first batch of RE01R's, with wire reinforce and way more grip than the current ones. I needed only a 3 to 4 PSI bias front/rear, higher in the rear. RE01R's required 32/36 generally to get good times, while with the RE760's i need at least 34/40 PSI without "squishing down" the sidewalls...
I will still be using the higher rears, the rear sliding feels better than the opposite with higher fronts.
That's my next project, after getting the current (frozen) bolts to come out from the suspension... I have a eibach front camber bolts waiting for a air impact wrench... D... No torch or WD40 have been able to take them out... a 350 tork electric wrench did nothing to get them either...
The lowering brought the rears up to -2 deg too... maybe sometime i will put the stock rear springs back and keep the front eibach, but it would look so much a 1/4 mile car that i guess won't be doing that...

Zzyzx

If you have to run high PSI on the front tires to keep them from rolling over (and cornering on their sidewalls) Its a sure sign that you are not running enough static negative camber.

as far as tuning balance with tire psi on the rear... it can be done, but it is a sign that you haven't found the proper balance with the rest of your setup. You see a lot more tuning this way in the stock classes, where they have little to no adjustments else where.

sdaidoji

iTrader: (1)

Yes, that's the reason i have the camber bolts waiting. I might need a rear camber soon, since it is running with 1.5 to 2 neg camber... good thing my car was already a underdog DSP when i did start autoX...