I had stiff swaybars but I hated how they act on FIA curbing so I did stiff springs instead, the end result it he same it controls the body roll to the same degree

sounds like our cars are setup about the same different way to get there but same result

 

And I want to keep the car streetable, so I stayed with the softer springs. Overall, I would guess that these two cars would be an interesting match out on the track.

Just an observation: I believe you still get some side to side weight transfer which gives you more ability to throttle steer. And because of my softer springs, I get some fore and aft weight transfer with the throttle (and brake) which gets me a bit more front camber under braking, which is good, but it also causes some understeer during acceleration, not so good.

 

I have much less body roll on the car with springs than I do on the car with jcw red & koni & rsb

 

But what about in comparison to my 27mm solid front sway bar and the rsb? I would guess the two cars are similar in static roll stiffness, but because each wheel is independently sprung in your case, there is still that opportunity for more weight transfer (in the dynamic situation of lifting off the throttle in a turn) than in my case where the wheels are tied together. I will admit to guessing a bit here, but I don't know any other explanation for why you have the throttle steering and I don't.

 

I never tried a stiffer front, with FWD I was told it hurts traction. The swaybar transfers torque to the inside spring, I have 8kg/mm front and 9kg/mm rear so it probably ends up similar

 

A stiffer front sway bar can help keep the camber of the front wheels from going positive when cornering.

 

stiffer springs does the same thing, along with more caster.

I prometer at the track, no camber issues up front anymore

 

Everything has its trade offs and pluses and minuses. Yes stiff front springs can mimic a stiff front sway bar, but they can hurt by making the car act like it has more unsprung weight than it really has. A really stiff sway bar works well at controlling body roll and camber changes but it also takes away the independence of the 2 wheels that it is connected to. Changing a front or rear sway bar without changing the other can have unwanted consequences in the balance of the car.

The ideal is to achieve a balance between the left and right sides of the car, the front and rear of the car and diagonally across the car. This is done with a balance between the shocks, springs and sway bars. And that balance is going to be dictated by driving style, speeds, track transitions, etc. And this doesn’t even get into caster, camber and toe-in.

I am by no means knowledgeable in this. But I have learned that there is no one sentence fix for handling issues (eg: Put in a big RSB, that will fix everything). That cost me a car. I have patterned my suspension mods after what MINI developed for the car, figuring they have suspension designers and probably spent millions that I don’t have putting together the options for the car. My objection was to develop a stiffer version of the balance they created for the JCW. One of the things they did was to match a larger RSB with a larger FSB, so, following their lead, that is what I did. Not very scientific but it worked for me. I have also added camber up front, but I balanced that with added camber in the rear. And I changed the shocks for ones with better valving (better control) and slightly stiffer.

One surprise out this setup was the almost total lack of throttle stressing. I didn’t expect that. It may be that my sway bars are too stiff and my springs could be stiffer to move the balance to be a little more like mega72 has.

One thing that I have noticed since I created this setup is the need for adjustable shocks. For a long track, like WGI, the B8s I have are about perfect. For a short, tight track like Lime Rock, they could be a bit stiffer. But I’ll live with it the way it is.

I like reading about the setups other people have and their reasons for going the direction they went. I am curious about how the OP makes out with the roll center adjustment.

 

have you looked at how the UK r53 race cars were setup? They do a LOT more racing over there, I found some setup docs and started with that.

Some of those guys run softer r50 swaybars up front

 

I have heard that (put in the smallest FSB you can find) from local FWD racers around here, too.

Are they also using high front spring rates, like yours?

I can understand this for racing, where being able to induce a bit of oversteer can be helpful. It is also really good for autocross.

 

I think it's to help the front hook up after apex where wheelspin is the worst, I can almost get inside wheel lift with the stock swaybar

 

LAP motors uses the Wave Trac LSD for that.

 

I think they all use LSD's too the spec cars had sequential gearboxes with lsd