[V-Kidd]

Since it's still off-season, I was thinking about playing with my sway bar setup some more. But first, I wanted to know what sway bar and tire pressure setups people are running and compared to stock (24mm/ 17mm), do you get a little, moderate, or an excessive amount of entry or exit oversteer?
Feel free to list any other suspension modifications that might help to explain.


My current setup:
27mm/ 17mm
35psi/ 35psi
Non-ACR wheels

• Non-Aggressive Daily Driving (street): WITHOUT any driver inputs to induce oversteer, I noticed more entry oversteer and very little exit oversteer.
  
• Aggressive Driving (street): WITHOUT any driver inputs to induce oversteer, there was a moderate amount of entry oversteer and a little exit. The back end feels like it's on the verge of breaking loose, but doesn't.
  WITH minor driving inputs to induce oversteer (throttle lifts and trail braking), there was enough oversteer to break the rear tires loose for a very brief moment on the entry. The exit remained the same.
  
• At The Limit (autox): N/A

 

[jinkly04]

well i have full bushing kit, bc coilovers, 650lb f 700lb r springs, pt turbo front, perrin rear sway, manny z rear lca's, full chassis brace similar to pwerks style, 8 pt roll cage, dc strut bars, 235/45/17 ra1 street tires :eveilgrin:eveilgrin. anyways depending on the alignment i have on the car it can become quite the oversteering little pig. i have noticed if i have a neutral toe setup it drives great and has no oversteer issues. as soon as i add any toe out to the rear it is an instant oversteer mobile. i usually run obout an 1/8 in total toe out in the rear just to induce a lil extra turn in.

 

[ibid]

I used to have BC Inverted coilovers w/hotchkis sway bars and liked that sway bar matchup much better than just going for a rear sway bar like I originally had a progress rear sway that wouldnt' work with the BCs

 

[Jonathan_]

I have the inverted with 12k/10k spring rates and the Hotchkis set.

On the street setting there's too much understeer, but I have yet to set it back to the tighter setting since installing the BCs (This is on road courses btw). I will be swapping it to the tighter setting before the next two track days.

I have 0 toe in the rear, and +0.1 in the front. It may or may not be exact anymore though.

 

[V-Kidd]

I used to have BC Inverted coilovers w/hotchkis sway bars and liked that sway bar matchup much better than just going for a rear sway bar like I originally had a progress rear sway that wouldnt' work with the BCs

I have the inverted with 12k/10k spring rates and the Hotchkis set.

Did you guys install the sway bar(s) first? The reason why I ask is because I want to know if the rear sway bar induced any understeer since the rear suspension is a strut type. Strut types lose camber due to strut compression, but with the addition of a stiffer sway bar, less camber is lost which means more grip in the rear [more understeer].

So I'm in a dilemma of whether or not to go with the ACR 19mm or stick with the 17mm. I can easily get rotation with the 17mm because the softer bar allows the rear to lose a lot of camber. But I am afraid that if I go 19mm, I won't get any rotation due to the extra grip.

If anyone out there has a stock ACR and also driven a regular SRT-4, please let me know how they drive in comparison with one another. I want to know why they increased the rear sway bar two extra milimeters.

 

[JohnyNFS]

I have K-sport GT revalved to accomodate the 850 front and 1000 rear springs. Hotchkis f/r swaybars set loose.
-3 camber front, -2.5 rear, 1/16 toe out in front, neutral toe in rear, 6point rollcage ( upgrading to 10 in a couple of weeks and going to stichweld the whole chessy )
B-woody Front H-Brace with tracktion bars (0 wheelhop)
tires: 275/40/17 at 32 front and 38 rear tire pressure

 

[Jonathan_]

Did you guys install the sway bar(s) first? The reason why I ask is because I want to know if the rear sway bar induced any understeer since the rear suspension is a strut type. Strut types lose camber due to strut compression, but with the addition of a stiffer sway bar, less camber is lost which means more grip in the rear [more understeer].

So I'm in a dilemma of whether or not to go with the ACR 19mm or stick with the 17mm. I can easily get rotation with the 17mm because the softer bar allows the rear to lose a lot of camber. But I am afraid that if I go 19mm, I won't get any rotation due to the extra grip.

If anyone out there has a stock ACR and also driven a regular SRT-4, please let me know how they drive in comparison with one another. I want to know why they increased the rear sway bar two extra milimeters.

I installed the Hotchkis set before the BCs. The "Race" setting gave way too much oversteer, but the "street" setting was pretty good. There was way too much lean with the stock springs/struts (not to mention they had 123k on them).

 

[stowaway]

I have K-sport GT revalved to accomodate the 850 front and 1000 rear springs. Hotchkis f/r swaybars set loose.
-3 camber front, -2.5 rear, 1/16 toe out in front, neutral toe in rear, 6point rollcage ( upgrading to 10 in a couple of weeks and going to stichweld the whole chessy )
B-woody Front H-Brace with tracktion bars (0 wheelhop)
tires: 275/40/17 at 32 front and 38 rear tire pressure

Have you looked into getting suspension pieces from the World Challenge teams? They did a lot of work to correct geometry problems. 3R Racing had some really nice pieces on their website. I bet they could still mill up some stuff for ya.

 

[V-Kidd]

I installed the Hotchkis set before the BCs. The "Race" setting gave way too much oversteer, but the "street" setting was pretty good.

Thanks for the input.

I've been thinking and I think I finally figured it out. The reason why the "race" setting gave you too much rotation is due to the increased tire lateral loads, lighter rear weight, in addition to the fact that the rear tires are fixed.

So that means that the ACR setup was a mistake in one way. Their decision on downsizing the front sway bar. With a smaller front sway bar, an ACR loses more camber than a regular SRT-4. But they "hide" the increased camber loss by inducing more oversteer with a stiffer rear sway bar. They made the right decision with the rear sway bar though.

 

[ibid]

I got the hotchkis AFTER the BC Coilovers..

in my case, the progress rear sway I had wouldn't work with the BCs... so I started out with the progress rear and stock front but was much happier with the hotchkis set up..

FWIW: I ran one track weekend with a mopar (I think it was ACR?) performance rear sway cause the progress wouldn't fit and I didn't want to run without a rear sway and it helped a little but the hotchkis matched setup was still much better IMHO

 

[IE Speed]

Hotchkiss, only setup I've had but WOW!!!!:wah?!::clap::clap:

 

[V-Kidd]

FWIW: I ran one track weekend with a mopar (I think it was ACR?) performance rear sway cause the progress wouldn't fit and I didn't want to run without a rear sway and it helped a little but the hotchkis matched setup was still much better IMHO

It sucks that the progress rear sway doesn't fit because it's actually stiffer than the hotchkis rear sway. Did you try using shorter end links?

And as much as I'd like to get a stiffer rear sway bar, I really want to keep my SRT-4 within D-Stock rules. So I can't go any larger than the ACR 19mm...

 

[valeriekay_2000]

I have the stage 3 coilovers, progress front/rear sway bars, mopar front/rear strut bars, full prothane suspension bushing kit, and solid motor mounts. I don't really know much about the alignment specs, but I had a good time at auto-x in Hawaii

 

[ibid]

It sucks that the progress rear sway doesn't fit because it's actually stiffer than the hotchkis rear sway. Did you try using shorter end links?

And as much as I'd like to get a stiffer rear sway bar, I really want to keep my SRT-4 within D-Stock rules. So I can't go any larger than the ACR 19mm...

shorther links would NOT have mattered.. .the way the progress bar is, it was hitting hard against the body of the BC Coilover... shorter links would have done NOTHING..

The hotchkis sway bar is positioned in the other direction (the ends) and the end links are slightly different.

If you do a search here, I believe I posted photos showing the exact problem and how there simply was no work around for it.

I found the hotchkis a vast improvment over the ACR bar I borrowed for one weekend of track use.. but you are right, the progress was thicker and allowed the rear end to be even more loose... the hotchkis made the car much more neutral... which isn't a bad thing either...

 

[McMoo]

It sucks that the progress rear sway doesn't fit because it's actually stiffer than the hotchkis rear sway. Did you try using shorter end links?

And as much as I'd like to get a stiffer rear sway bar, I really want to keep my SRT-4 within D-Stock rules. So I can't go any larger than the ACR 19mm...

Just so you know, you can't use the ACR sway bar unless you have an ACR, or convert your car to have ALL options that were on the ACR, you can't pick and choose. It's kinda stupid but that's the way the rules are. So you can't use 16x7 wheels, stuck with the 17x6's too.

Topic question.
I have the PT 26mm front and the perrin 22mm rear. The car is nuetral to a little oversteer with -3* camber up front. It's a very safe setup, but probably not the fastest. My brother's 06 civic si with just a bigger rear sway bar is way more tail happy, but my car feels planted and more controllable. This is with s3 coilovers on full stiff front and back.

 

[stowaway]

Just so you know, you can't use the ACR sway bar unless you have an ACR, or convert your car to have ALL options that were on the ACR, you can't pick and choose. It's kinda stupid but that's the way the rules are. So you can't use 16x7 wheels, stuck with the 17x6's too.

Topic question.
I have the PT 26mm front and the perrin 22mm rear. The car is nuetral to a little oversteer with -3* camber up front. It's a very safe setup, but probably not the fastest. My brother's 06 civic si with just a bigger rear sway bar is way more tail happy, but my car feels planted and more controllable. This is with s3 coilovers on full stiff front and back.

only if you want to stay in stock class. Get out of stock class and you are open to anything.

For your car, try setting the fronts at half stiff and leave the rear at full stiff. You'll get a bit more rotation and better front grip.

 

[McMoo]

only if you want to stay in stock class. Get out of stock class and you are open to anything.

For your car, try setting the fronts at half stiff and leave the rear at full stiff. You'll get a bit more rotation and better front grip.

Right, he said within d-stock rules. I'll try that in the spring, although I'll have 459/345 springs on then, so I was planning on messing around with it then.

 

[stowaway]

he can't even go to the 19mm acr bar unless he changes over EVERYTHING that differentiates an ACR from a non-ACR. That includes seats, vehicle speed sensor gear, rear swaybar, and wheels. Only the badging could be left off. He would also have to be driving an 05 car to be able to do any of this.


When I was stock, I installed the 19mm rear bar and it definitely decreased understeer. It didn't result in oversteer under anything but stupid manuevers. I later put on the 26mm front bar and understeer increased. Just like physics and vehicle dynamics say it will.

 

[ibid]

If I was stuck with an 05 ACR, I would have at the very least made sure the shift fork was changed.. lol

 

[V-Kidd]

he can't even go to the 19mm acr bar unless he changes over EVERYTHING that differentiates an ACR from a non-ACR. That includes seats, vehicle speed sensor gear, rear swaybar, and wheels. Only the badging could be left off. He would also have to be driving an 05 car to be able to do any of this.


When I was stock, I installed the 19mm rear bar and it definitely decreased understeer. It didn't result in oversteer under anything but stupid manuevers. I later put on the 26mm front bar and understeer increased. Just like physics and vehicle dynamics say it will.

I have an 05 SRT-4, so the seats should be the same weight/ specs minus the badge. What's the vehicle speed sensor gear though? If all it does is measure the speed I drive, then I shouldn't have to change it because it doesn't serve any other purpose but act as a "gauge". Also, I am investing in another set of wheels and tires (16x7) for autocross. So ultimately, I only need 16x7 wheels and the 19mm sway bar, then I'm set.

In a Macpherson strut suspension, the goal in choosing sway bar setups is to find the stiffest front sway bar as possible because it will prevent the car from losing camber. If you lose less camber, you get more grip in the front. Increasing grip in the front will give you more oversteer. See what I mean? That's the logic to the SCCA stock rules about sway bars.