BigJim

So i do some autocrossing during the summer. usually try to get 3 or 4 events in. The problem i typically have is that when i take a sharp turn the front tires wont hook up and ill just slide straight unless i let completely off the throttle and even then it will still slide straight. Obviously an effect of taking the corner to fast, but nothing that cant be solved by using a better tire.

I currently have Bridgestone Potenza RE750's p235/45/R17 94W on the fronts and then the same but for a 10 in wide wheel on the rear.

I dont seem to have any issues with the rear gripping so i am planning to only buy a set of tires for the front, for now, since thats where my problem area currently is. I also already have a set of wheels for the front just need the tires.

I have been looking at the BF Goodrich g-force T/A drag radials and the BF Goodrich g-force R1 tires. I am thinking of going with the T/A drag radials because they are about $80 cheaper per tire.

Do you guys think this is a good solution to my problem, if not, what would you suggest?


This is for a FD btw.

hyperlitenerd

iTrader: (1)

I would suggest checking out your tire pressure. I had to tweak mine for a while to get it gripping how I wanted. The only other thing that comes to mind is are you coming in too hot? Old saying of go slow to go fast.

BigJim

Yea i know i am coming in to fast for the corner, otherwise i wouldnt be sliding through it, but i just feel that the car should be able to stick better than it does.

If i start to turn then floor the car it will push the car straight ahead and slowly hook and turn me.

I have tried lowering the psi, and raising the psi, nothing really seems to help. The front just doesnt want to stick to the track.

jdmsuper7

iTrader: (1)

Drag radials are NOT intended to be used that way and most likely your grip will get worse.

The R1s are designed for track use and won't get nearly hot enough to be effective over the course of a few runs. Not only that, you really really don't want to run an R-comp style tire on only 1 end of the car.

I'd suggest Bridgestone RE01s or Dunlop Star Specs, they are about the stickiest street tires out there and are designed specifically for the ST classes. The Falken Azenis are also quite good for those on a budget. That said, you won't understand how much stickier these tires are until you drive on them. I switched from RE750s 2 years ago and the car felt like a whole new animal on the Falkens. The 750s, which I had thought were pretty sticky, look like snow tires by comparison (the same thing happens when you make the leap from ST tires to R comps). You may well have a serious over steer problem running them only on the front, even with the extra width on the back. I really recommend re-shodding all around if you are going to go with something in this class.

I also recommend braking harder and/or taking a more gentle arc. That may well cure your understeer.

Mahjik

iTrader: (1)

What is your wheel size up front with the 235's?

Kentetsu

Hey Jim,

I'm running an fb in autox, but I feel your pain. I spent my first two years fighting understeer. Finally got a pretty good handle on it this past year by making suspension changes and changing my driving style. Slower in, faster out makes a huge difference.

The thing is though, the car handles pretty much the same way whether I'm running the Hoosiers or the Sumitomos (I go a lot faster on the slicks, but the car handles about the same). So tires alone might not solve your problem. The suspension changes that I made were stiffer in the rear (shocks, springs, swaybar), adding a bit of toe-out before races, and lots of camber.

"How to make your car handle" is also an excellent resource for getting started in the black magic of suspension and handling tuning. Good luck...



.

BigJim

they are 7.5 inches wide on the front.

ill look into the re01's and the azeni's. i just want something thats really going to grip the track, i would rather have to much grip than not enough ya know. Note that these tires will only be used on track days, never on the street.

Mahjik

iTrader: (1)

That's your problem. Even though you are using a 235 on front and back, with a 10" wide wheel you'll still have more of a tire footprint in the rear than in the front. That's going to create understear. Do you have an adjustable suspension and/or adjustable sway bars? You'll have to use your suspension to dial it out.

BigJim

I think i saw you at one of the autox's Kentetsu. I unfortunately cant afford a set of coilovers currently so i cant really fine tune my suspension.

jdmsuper7

iTrader: (1)

How many events have you done total? Stepping out of the street tire world is probably not something you want to do right away. R comps tend to hide alot of bad habits.

Get the falkens, and mount them on equal size rims all the way around. You'll be really pleased, should get ~150 runs out of them, and they will really help you learn to drive well.

And for the record, the 205/225 stagger I started on also understeered like whoa. It doesn't seem like stock suspensions likes it at all.

BigJim

ive done 6 events. 3 in the fb 3 in the fd.

TrentO

I agree with the rim widths a bit. What do you have for camber on the front?
Even without coilovers you can adjust for a bit of negative camber.

-Trent

hyperlitenerd

iTrader: (1)

+1 on alignment, look up the pettit alignment specs for starting place. I think I am running -1.2 all around on stock suspension.