Comptech front bar provides a range of adjustment that is between 62% and 178% stiffer than stock, with five total adjustment points.

Mugen front bar how many % stiffer than stock?

I have F225/45R17, R255/40R17 tires, my stock car have too much oversteer. Wich is the best answer for my problem?

 

According to this thread the 31.8mm Mugen bar would seem to be somewhere around 70% stiffer than stock (I'm using numbers from other bars to get the 70%). It's also important to note that the various numbers generally relate to an early AP1 so you have to factor that in. You seem to have an AP2 which has different bars and stiffnesses. Since the AP2 has a smaller rear bar with thinner walls, that increases the effect that the front bar would have. However, this may well be not enough stiffness for R compound tires with a good driver.

You seem to be indication that you're on street tires and that you're not that experienced in autocrossing. If this is the case, oversteer is very likely to be a driver problem. You can get the car to oversteer even with a tree trunk up front. Also, the alignment has a profound effect on handling.

So, answer these questions so better answers can flow:

1) What form of racing are you doing?

2) How experienced are you in the above?

3) How experienced are you in a RWD car?

4) What year car?

5) What tires?

6) What alignment?

7) What, if any, other suspension mods have been done?

 

Mugen Front Stabilizer - 25.4mm [51300-XGS-S0N0-B2]
www.kingmotorsports.com


I have sufficient experience, MY03, Yokohama Advan A048 tires. The car is 100% stock, and i go with stock alignment. I have no suspension mods!

If i go out of corner i can`t step on gas, because my car have too much oversteer. My plan is a stiffer front sway bar, but the 25.4mm Mugen bar is OK?

The stock front sway bar cca. 30mm... Mugen 25.4, but stronger, stiffer?

 

According to the thread mentioned above, the stock '03 front bar is 26.5mm, not 30. So, the Mugen bar is smaller but you'd need to know if it was solid or hollow. If hollow, what's the wall thickness? I'd wager it's stiffer but not by much.

Most folks seem to be running wider rears - that may help. Also, more rear camber would help control oversteer and maybe a bit more toe-in.

Since you're tracking the car and not autocrossing, I'm not the best person to be responding. (Well, for that matter, maybe not for autocross, either. ) Maybe someone else can kick in with suggestions?

 

Stock alignment is a problem. Dial in some negative camber and call me in the morning.

 

I can`t call you, because i live in europe.

The maximum front negative camber is -1.00 degrees (stock -0.30)
rear camber: -2.00 (stock -1.30) degrees.

What is faster: maximum negative camber at all wheels or -0.7 degrees at front and -2.00 at rear for compensate the oversteer?

I can`t use wider rear tires because my wheel is 8.5" wide, and i already used 255/40R17 tires on it.

 

Well, it depends on whether you're after controlling oversteer or inducing understeer. You *can* use wider tires as long as they don't rub - I use 265/45-16 on the rear AP1 7.5" wheels for autocrossing. I think AP2 cars can easily use 275/something on the rears with no/little rubbing.

Personally, I'd try more rear camber before less front camber...

 

 

What?

First, stock is 0.5*, 1.5*. You have confused minutes (sixtieths of a degree) for points to the right of the decimal place.

Second, why do you say max front neg camber is -1.00 degrees. I'm maxed out at -1.4*, with 6* caster, and I'm getting less negative camber than most.

Just FYI:
I'm running:
-1.4* front camber,
-2.3* rear camber,
0 front toe,
3/16" rear toe IN, (edited)
Comptech Adj FSB on medium stiff (3rd of 5), and
225f / 265r Kumho V710.

I'd say the car is understeering, but if I set the FSB any less stiff, I get inside rear wheel lift in tight corners.

 

Check this!

Front camber -1.00" , rear -2.00".