Can I have compound autocross tires up front and street tires in the back

[SRiz]

I have falken ziex 512 that I just got and have great treadwear rating and are quiet on the highway. I just got back from an autox and I was understeering the whole time. I eventually got the pressures of the tires right and had the shock adjustments dialed in after 3-4 runs. I know I can get a rear sway and strut bar, but I really want a set of autocross tires.

My question is will there be any drive train stress/damage using a autocross tire up front and street tires in the rear. Im not going to be sideways spinning all four using this set up. I have two extra rims, so the tires will be the only expense. Im in college thats why im trying to go cheep.

Thanks!!!

 

[necrotopsy]

the 512's are cheap tires anyway($89 a tire last i checked). and they have horrible tread wear. the warranty on them is only 40k miles.

sorry idk about autocross tires, but now u have my $0.02 on the 512's

 

[SRiz]

yea thats why they are my dailiy tire. At autocross they suck, no grip, shitty sideway, ect. Im asking about putting road course/autocross tires in the front of the car

 

[Scott McIntyre]

If you put race tires on your car, you'll want them at all four corners otherwise the car will be virtually undrivable at the limit.

 

[ACM]

To find out whether this is a valid proposition, retain your current front tyres and add a pair 0f very narrow Blizzak WS50s to the rear wheels at about 15psi. If you can tolerate the oversteer/looseness this setup produces, you'll likely be able to tolerate the oversteer from A6s in the front and non-A6 tyres in the rear.

I greatly admire your fortitude, please post your testing dates so I can stay home

New, good competition tyres have substantially more grip than the very best street tyres available. You could probably get away with several-year-old R-comps if they're well heat cycled and you have good rear tyres. Instead, try some of the 'second-string' ST* autocross tyres instead of R-comps, they will give you better grip with tolerable balance. Something like the Dunlop Direzza (non-Star Spec), the Hankook RS-2, BFG KD/W, etc. Any tyre that was a good ST* autocross tyre several years ago - ie uncompetitive today - should give you what you're looking for. In all likelihood you'll still have balance issues, but playing with tyre pressures and particularly adapting your driving style will help.

FWIW, a great driver once said that all understeer is always driver-induced, unless mechanical failure is involved. As true as it gets.

Charles

 

[SRiz]

I heard there is a site that sells used compound/ racing tires. Im tring to get 235/45/17 which isnt hard to get for my street tires, but seems a bit harder for autocross tires. If anyone knows where I can get used tires in that size let me know. I wouldnt mind having oversteer at all. Understeer is just so shitty around cones, ill pick a great line and if i late break at alll the car will plow foward. If the only downside of having race tires up front is I will oversteer then my question is answered... I WANT!!!!!

 

[ACM]

The reason you're understeering around the cones is because you're trying too hard. Too much entry speed, too much brake, too much steering input. Back off. Slow down, feel what the car is doing. You're understeering because you are not listening to what the car is telling you.

Until you start listening to the car, adding any go-faster parts will not help you. Indeed, competition tyres are far more sensitive to driver input and overheat much, much faster, add that to the typical used race tyre has been heat-cycled to death, you may end up actually posting slower times.

Find a local guy who's at the top of the PAX numbers, look for someone you get along with and will tolerate your presence. Stick to him/her like glue, take them with you on every run they will tolerate, and ride shotgun with them as often as they can stomach. You will probably work through several people before a mutually acceptable relationship develops. This is how you will improve. Not by throwing parts - specially already-worn-out parts - at the car. The best $300 you will ever spend will be on an Evolution driving school - provided you listen to the instructors. I have watched locally mid-pack drivers argue lines with multi-time National Champions - not the most productive approach !

This is how you get fast - you learn how to drive. Lewis Hamilton, Jenson Button, Seb Vettel, Fernando Alonso even Schumacher, they all have driving coaches. They are still learning to drive faster. If you think you're better than them then fine, throw $$$ at your car.

I'll bet you that there are at least half a dozen drivers at your local autocross that can take over 5 seconds off your best time in your car whilst driving one-handed as they point and explain how to drive the best line. If this isn't the case then I expect to see you at the 2011 Nats in Lincoln

FWIW, I did the same thing when I first started autocrossing, until I got slapped upside the head and shown what my car could actually do with a competent driver behind the wheel.

Charles

 

[D_Eclipse9916]

*cough* summary...track time track time track time....and of course instruction. One thing is to get opinions from the better drivers out there, but dont always take it for the golden truth, remember some people go fast "despite" their fallacies, and there may be better ways. National type guys still argue over lines, and sometimes theres just not one "fast" way.

PS- Get some wheels thatll fit a 245/40/17 properly and harass your local STU guys. We regularly heat-cycle out our competitive tires before the tires are even remotely "finished". Plus its a tire you could drive on and is cheap. A 245/40/17 Dunlop Star Spec is a cheap tire thatll remain competitive for a good 1/2-3/4 of a season and 99% competitive for long after that.

 

[ACM]

That is very true, however given the description of the problems, no amount of unsupervised seat time is likely to work - and even if it did, supervised seat time would be vastly more productive.

Any local class champ is going to be of help, though yes, some more than others, which was my point about trying different instructors out.

Most serious autocross clubs have a group of instructors, drivers who are generally agreed upon as being the best in the club, work through them and choose the best fit.

Charles