alpinaturbo

iTrader: (5)

My car is developed by Paul Gerrard, with his philosophy Keeping Wheels Independent, therefore still on stock sway bars.

In part this may have been motivated initially by the expense/difficulty swapping front sway bar- and of course not wanting to decrease rear grip to dial out understeer by upgrading only rear sway bar.

What about upgrading both sway bars: recommended?

OEM Evo sway bars are small, my Miata turbo uses Racing Beat 1.25" front and 11mm rear bars, to properly balance the 700/450 spring rates.
Even upgraded Evo sway bars are not outrageous by other standards: 26mm front for example.

Thanks for input.
Car is on Gerrard Ohlins 10kg front and 12kg rear spring rates, all properly dialed in.

MinusPrevious

iTrader: (3)

Ive inquired more than a few times w/2 of our EVO Guru's (Robi & Mueller) Both have noted a similar opinion
The stock FSB is not to be changed on a track day EVO. Stiffening the rate of the FSB tends to lift the inside front wheel in tight, high speed corners.

Lifting the inside wheel maybe Ok on BMW's or Porsche's, but its a power killer on our AWD's

Robi noted that the stock FSB with his adjustable endlinks (& of course, all his other bits) is the ticket

A lot of opinions on this topic & a lot of guys here run the higher rate FSB

nollij

iTrader: (21)

What tires?

KevinD

iTrader: (56)

We raced several seasons with stock fsb. It allowed to much body roll and we couldn't dial in enough camber to keep the tire wear even.

Now we have the Whiteline front bars in all our race cars.


We have also upgraded our dampers significantly as well recently so as we dial in these shocks we have been playing with different bar settings on the rear and may play around with the front again as well.

killerpenguin21

iTrader: (20)

i have gerard spec ohlins paired with whiteline F/R bars. car is very good, stays nice and flat and weight transfers very controllably. i certainly cant use all it has to offer at my driver skill level yet. i am however having inner shoulder wear issues on my front tires (-2.8 camber zero toe)...need to have my alignment checked and redo some bushings i think...

alpinaturbo

iTrader: (5)

To answer the posed question:

I run BFG R1, but have also taken it as goal to "learn" to drive well on street tires and take part in Extremespeed time trials on street tires, to really learn how to drive.
So both, R compounds up to maybe Hankook C51, and down to 140 thread wear rating street tires.

Minus Previous notion by Robi and Mueller that stock FSB is perfect because anything more and the front wheel will lift is very important and interesting fact.

As noted, my spring rates are 10/12kg, and tires from street to sticky more sticky R compounds, including Hoosier and more.

I am curious why Robi offers 26mm front bar? And Whiteline, too, if it does not really work well?

Ralliart Gr N cars run upgraded sway bars- with the 3 and 4 way adjustable rally coil overs.
I am fine with leaving well alone, but am tempted to upgrade when its easy and cheap- but concerned as ever to ruin a good thing.


I checked AMS Time Attack Evo 8 spec when it was advertised for sale back in 2007- and no mention of upgraded sways.
I checked Nils L Street Class time attack cars spec, and no front sway bar upgrade.

Mueller's recent customers Evo 9 RS that is such a nice dual purpose car ran stock FSB, when I saw it at Laguna back in 2012, and I think Mueller ran it at ExtremeSpeed event this year winning class, but no mention at least of FSB upgrade.

Robi's front sway bar is adjustable which is a little of an advantage over Whiteline perhaps- giving an option to fine tune.

KillerPenguin21's use of front and rear Whiteline confirms that they can be used successfully. And I trust I am similarly skilled- meaning novice with experience but not seasoned competitor.

I mentioned, two successful race-setup professionals highly suggested to upgrade sway bars: one is former Indy and NASCAR crew chief, now running a circle-track prep shop in SF Bay Area, the other is professional sports race car shop owner/fabricator/setup/driver in the SF Bay Area- a winning sports racer with ability to setup and to drive- resulting in track-records.

They both subscribe to use of sway bars up to a point- because in their words, at some point heavy spring rate decreases traction. And I think in their minds on a 3000-3500lb car a 1.25" bar is totally acceptable. So 26mm FSB on Evo is within reason well fitted to the application.

Stilli in dilemma.
I look forward to more thoughts and experience

killerpenguin21

iTrader: (20)

my car had both bars on them when i bought it and they were paired with bilsteins and gtworx springs, so obviously a soft spring. right now im running 8k/10k with 26mm front bar and the adjustable rear on full soft. at my current skill level neutral to understeer is where i need to be, and i think i have achieved that as even when trying pretty hard an experienced evo driver/myself cannot intentionally induce oversteer...of course i have caused in with errors lol.

the question is what will happen if i go up on the spring rates. i do still have some body roll but certainly dont think i will ever lift a wheel.

i think there are some people that may have better data/experience than me tho.

golgo13

iTrader: (134)

I asked about this as well.

https://www.evolutionm.net/forums/ev...ring-rack.html

Dallas J

iTrader: (1)

You need to control roll, you can only run so much spring before bumps start upsetting the car too much, and you cant do much about roll couple. So that leaves you with swaybars to get enough roll resistance.

alpinaturbo

iTrader: (5)

Guys,
Thanks so much

I think last two posts are tipping the stale mate to swap both sway bars.
So the tri-podding is due to stiff rear and no front- rather than both upgraded sway bars.

While I am upgrading the short block it is very easy to upgrade sway bars-and rear is at home, so all I need is front.

Although Whilteline is widely used and definitely great, have rear, I am thinking Robispec front as its adjustable- giving a little more "forgiveness" should I run into needing any softening.

Any opinions here?

The holes on the Robi bars are pretty close together but if I were to guess I would say maybe still there is 10+% stiffness change between the two.

There is a Whiteline for $100 available which is sweet deal compared to Robi $250 + Tax +shipping.
But would rather not make $200 dollar decision just for cash -value, would like to make best technical decision

Inputs?

Dallas J

iTrader: (1)

Tri-podding is more due to front dive but un-even bars do have an effect. A stock evo has 50% of its roll resistance come from the bar, both front and rear. Keeping that ratio front to rear about the same helps keep the car rolling flat. Though if you have heavier rear springs then youll need a little less rear bar or... Tri-pod.


Get the whiteline bar and the cusco FSB bracket. -14%/0%/+16% for adjustment.

alpinaturbo

iTrader: (5)

Awesome idea, Cusco Bracket

Thank you. That certainly will put concerns aside, having some adjustment to fine tune the behavior

griceiv

iTrader: (2)

the tripoding is due to the 60%+ nose weight. If it doesn't tripod with that much nose weight you've sacrificed lateral grip capability.

golgo13

iTrader: (134)

So then this image I've been championing for a few years now is actually correct:

heel2toe

iTrader: (41)

This comment really sticks with me so I'd love for you to expand on that. Below is a picture of my car from an autox over the weeekend. Car is on Ohlins DFVs 8k/10k TRE Maxxlock various bushings etc.

I current have a Perrin (Progress I believe) 25mm with matching endlinks on the softest setting. The front I still have my stock bar but I drilled it and have the endlinks currently on the stiffer setting. My tires are ZII's 255/40-17.

On corner entry I am still lifting the inside rear wheel. Now the car does handle really well however there is always room for improvement. I have a couple of thoughts but am looking for peoples feedback.

1) Leave well enough alone
2) Put back on my stock RSB
3) Purchase Cusco/ Ciro Design Racing FSB bracket
4) Purchase larger FSB
5) Get some 12k springs for the rear and put my 10k on the front
6) A combination of some of the previous ideas

I guess the question remains as to whether lifting a wheel is detrimental to my cars handling. Is it something to be concerned with? I'm guessing that the lifting of the rear wheel is helping with rotation on corner entry however I also believe that the more tires on the ground the more ultimate grip my car has which should help things like slaloms.

Please advice and thanks