1LE suspension upgrades advise

[vhawk]

Originally Posted by JusticePete

The 285s squared are mission critical to the handling of the 1LE. If you go to 305s in the rear and stay with 285s up front you are back to the understeer found in a SS or damn close. The Z/28 runs 305s squared. My Pedders USA Camaro ran 305s squared way back in 2009. If you add 305s to the rear, finish the job with 305s up front

I have a 2012ss with 255s up front and 285s in the rears + 1LE suspension package including 27mm front and 28mm rear sway bars. Does this mean I am in the understeer zone? What can be done about this?

[jksynergy]

Originally Posted by vhawk

I have a 2012ss with 255s up front and 285s in the rears + 1LE suspension package including 27mm front and 28mm rear sway bars. Does this mean I am in the understeer zone? What can be done about this?

Yes you are in the understeer zone. The 255’s up front are the main cause. Not enough of a footprint on the ground. I’d suggest moving to a 285 square on a 20x10 wheel. Even 275 square would be better than what you have now. And you can run a 275 on a 10” wide wheel without issue. What is your our main goal?

[vhawk]

My main goal is a daily driver with good track and drag race capabilities when I take it to the track.
The problem with the fronts is that they are 9" and the rears are 10.5".

Are there any options with the current wheel setup or do I have to change the fronts to 10-10.5" anyways to move it into steer/oversteer zone?

[SSammy]

There isn’t one setup that will be best for all. There are always trade offs. Your best track tires won’t be great in the rain, best drag race setup won’t be good for street or track, etc. I went with a compromise, 275/40 all seasons on 20x10’s for all 4 corners, not the best for any one thing, but I can air down the rear for a dig but the wider fronts increase roll resistance & drag, I have less understeer than stock on the street and track, my car has good, quiet street manners, I can drive in the rain or light snow, and can rotate my tires for more tire life. It is all a decision on what you want your car to excel in.

[jksynergy]

SSammy, makes some great points. A 275/35 would work just as well with a slightly wider footprint up front. It's going to come down to how much are you willing to spend and making a really good choice. For tires, it will be what can you afford that does what you want. Wheels will be the same. Pick a wheel that saves weight and doesn't break the bank. Plenty of choices for both.

Sent from my SM-T377T using Tapatalk

[vhawk]

Does the 32mm rear sway bar require a squared setup?
What happens if you have 255s up front and 285s in the rear but set that sway bar to medium or hard setting? Won't it make the car oversteer?

[SSammy]

Originally Posted by vhawk

Does the 32mm rear sway bar require a squared setup?
What happens if you have 255s up front and 285s in the rear but set that sway bar to medium or hard setting? Won't it make the car oversteer?

I have my sways on the middle hole (BMR 32mm rear & 29mm front) and it’s balanced running square. You may be able to get enough rear bias with a sway bar to induce balance or oversteer, but I haven’t tried with a narrower front tire. I installed my sways after the wheels & tires.

[vhawk]

Btw, what about additional front weight added by the TT kit? This is likely to increase front grip and reduce understeer, isn't it?

[VR Baron]

Originally Posted by vhawk

Btw, what about additional front weight added by the TT kit? This is likely to increase front grip and reduce understeer, isn't it?

More weight up front lessens steering response and causes more understeer . And with small front tires understeer, like a stock car, is worse. Best tires for grip, handling and supporting weight has long been known to be305 wide on 19” wheels. But if you are sticking to 20” wheels do the 285 wide tires.

[mikeman]

Originally Posted by SSammy

I have my sways on the middle hole (BMR 32mm rear & 29mm front) and it’s balanced running square. You may be able to get enough rear bias with a sway bar to induce balance or oversteer, but I haven’t tried with a narrower front tire. I installed my sways after the wheels & tires.

That's only a 3mm difference though. I thought it should be more like 5 - 6 mm for best balance from what I've read on here.

[VR Baron]

Originally Posted by mikeman

That's only a 3mm difference though. I thought it should be more like 5 - 6 mm for best balance from what I've read on here.

The bmr 32 rear bar has a monster 1/4” wall. The front bar is 3/16”. I bet the difference is about 4-5 mm in actual bias. That’s all you need for a square setup. Five mm bias is fine for stock springs and staggered tire setup

[mikeman]

Originally Posted by VR Baron

The bmr 32 rear bar has a monster 1/4” wall. The front bar is 3/16”. I bet the difference is about 4-5 mm in actual bias. That’s all you need for a square setup. Five mm bias is fine for stock springs and staggered tire setup

1/4" wall tubing? Man, that's pretty thick. That's probably the closest thing you can get to the solid JPSS rear bar.

[VR Baron]

Originally Posted by mikeman

1/4" wall tubing? Man, that's pretty thick. That's probably the closest thing you can get to the solid JPSS rear bar.

On the stiff setting it’s pretty close I bet. My dse 35mm x 3/16” wall on stiff is like a 32 mm pedders (jpss) bar