Balance

[d1ck]

So I've got a problem, and I'm hoping some of the guys who are experienced with setup can help me out here.

First I'll tell you my previous setup which was amazing:

225/45 BFG Rivals on RPF1
Whiteline Com-C Front Mounts
-3 Deg Front Camber
1/16" Total Toe Out Front

-2.5 Deg Rear Camber
1/8" Total Toe In Rear

KW V3 w/ swapped springs 400F / 380?R

This setup worked really well for me, it seemed to be very well balanced and I could steer with the throttle, or settle the rear end coming out of a corner with just a little throttle input. The turn in was fantastic and it always seemed like the front had limitless grip.

Then, I wore out my Rivals and things went to shit. I put on a set of 215/45 RE-11A and installed the Strano Parts front sway bar. I also swapped the springs back to the intended setup (380?F / 400R). As such I had to reset the ride height and have the car aligned again. The ride height is a little higher now because I wanted to take out some rear camber due to the inside of the rear tires wearing more quickly. I had the car aligned with the following settings:

-3 Deg Front Camber
0 Toe

-1.5 Deg Rear Camber
3/32" Total Toe In (It's actually .2 Degrees but 3/32 is very close)

I race autocross on a runway normally. The runway is about 90' wide x 2,300' long so you can imagine our course designs are a little limited. We mainly have gates which are offset to opposite sides of the runway with a few slaloms and lane changes in there. There's also normally a pin to turn around at the end.

With the setup as it is now I'm fighting the car to make it turn, and the only way I can make it oversteer at all is by really upsetting the car. I generally try to drive smooth with no trail braking so I like to keep it tidy but this is too much. I was beaten this week by a another driver in a stock FRS on Rivals who has never beat me before this event. I've got another event this upcoming weekend so I want to do everything I can to get this sorted ASAP.

Thanks for reading.

[kiichiro]

Go back to stock

[7thgear]

i think you're in the same boat as me now


too much front stiffness gets your front loaded quicker and hence understeer and difficulty to oversteer

[d1ck]

I should add I've tried playing with tire pressures and damper settings at two events now with no noticeable improvement.

[Racecomp Engineering]

Stiffer front rates with a big front bar can do that. Is it adjustable? Putting that back to stock or increasing your rear rates (if you must have that extra roll stiffness). I'd probably lean towards just putting the stock front bar back on, at least to start.

- Andy

[d1ck]

Originally Posted by Racecomp Engineering

Stiffer front rates with a big front bar can do that. Is it adjustable? Putting that back to stock or increasing your rear rates (if you must have that extra roll stiffness). I'd probably lean towards just putting the stock front bar back on, at least to start.

- Andy

Thank you for the input. I actually made a mistake in my post and right now I have the stiffer springs in the rear, and softer in the front. However, I'm going to try removing the Strano bar and putting the stock on back on.

[wparsons]

Why so much rear toe in? Before swapping out parts I'd zero the rear toe and see if that helps enough. If not, you'll either need more rear spring rate or a softer front bar (stock?).

[DarkSunrise]

Originally Posted by Racecomp Engineering

I'd probably lean towards just putting the stock front bar back on, at least to start.

Originally Posted by wparsons

Why so much rear toe in? Before swapping out parts I'd zero the rear toe and see if that helps enough. If not, you'll either need more rear spring rate or a softer front bar (stock?).

As these guys have said, stock front bar and/or zero rear toe would be the easiest places to start.

[SubiePig]

That is a 75% increase in front roll stiffness and none in the rear so the car will be a bit pushy. I ran the same setup, on RS3's, for a while this season and it was not fun to drive. I run an 18mm rear whiteline bar now and its much better. either go back to the 400F/380R spring setup or get a bigger rear bar and get rid of some of that toe-in on the rear.

[d1ck]

Thanks for all the input guys.

The reason I've got some rear toe in is that I have found that with some toe in the rear will come back in line much easier when I get some over steer. It makes the car easier to drive, but I guess there is obviously a fine line there between too much and too little.

Can anyone comment on the tires? From what I've read they're not quite equal to the Rivals but shouldn't be that much slower either.

Also, which would ultimately prove to be faster between putting stock front bar back on, or upgrading rear?

[Racecomp Engineering]

Also, the standard spring should be 336 lbs/in rear IIRC for KW V3, not 380.

We generally run even rates front and rear (400/400).


- Andy

[wparsons]

Depends on how close you are to lifting the inside rear right now. Too much bar in the rear will make it hard to put power down on turn exits since it'll unload the inside tire.

Another option is to put the higher rate springs in the rear and the softer ones up front, with your current sway bar but that's a lot more work than less toe or less front bar.

[SubiePig]

Originally Posted by d1ck

Thanks for all the input guys.

The reason I've got some rear toe in is that I have found that with some toe in the rear will come back in line much easier when I get some over steer. It makes the car easier to drive, but I guess there is obviously a fine line there between too much and too little.

Can anyone comment on the tires? From what I've read they're not quite equal to the Rivals but shouldn't be that much slower either.

Also, which would ultimately prove to be faster between putting stock front bar back on, or upgrading rear?

It will make the rear more stable but it doesn't need much, you are going to have a lot of tire wear with that much.

I have never run the RE-11A so I don't really have a good opinion of them. On a general perspective they were at one point one of the go to tires in street classes from what I remember but not for a few years. Everyone is on ZII's or RS-3's. RS-3's being my preference.

Increasing roll stiffness helps with transition speed and weight transfer but a stiffer car is overall harder to drive consistently as the grip limit falls off faster. Competitively the car needs a stiffer bar setup and I like the way mine is now with the equal stiffness increase.

[blackhawkdown]

Why upgrade the suspensions when stock suspension is kicking your ass? You could put the money to something else?