No way would I get an AO48 over the Hoosier or V710. The AO48 is a road course tire. Honestly, the best tire to use making the transition into r-comps would be the Kumho Victoracer. That was my first r-comp in autox and I loved them. They have good grip and will last a looong time. You can also get them in a 255/40/17..which is what I used on the stock rim.
Another option you could consider is running the Hoosier R6. It's the road race compound but it will be plenty sticky to be competitive at local events AND it will last alot longer. It realy depends on your budget, and what you are trying to accomplish. You can ruin a set of A6's or V710 QUICK if you overdrive them. The breakaway characteristics are also way different on something like the A6's. Not nearly the warning at their limit like the tires you are used to runnning.
BTW, my first year with the Victoracers I won both my local regions (SCCA, CSSC) in ESP (back then the Evo was in ESP not BSP)
If you are worried about rubbing the 255/40 won't rub anymore than the 245/45. My friend ran 245/45 Victo's the same year I was running 255/40's.
The 245/40 Hoosier is a good size that doesn't rub at all. I used both compounds in that size for a while also....0 rubbing.
Now I run 285/30 Hoosiers with 18x9.5 wheels.

 

You can run whatever you want, but to run that setup, you'll need to choose the right rims with the right offset, the right spacers, a proper coilover setup with around -3.0* camber up front, and some fender rolling. Oh, and the tires will be closer to $1200.

 

Don't do it! You are crazy if you jump right into a 285 setup. If you can drive you can be competitive in BSP with minimal mods and 245 or 255 r-comps. You need to progress up to the 285 imo.

 

I couldn't agree more.


The biggest factor will always be the driver. Rushing into a "more competitive setup" without addressing the driver factor is a recipe for either burning more money with no results or getting your *** handed to you and don't disasslusioning you on the sport.

Once a year, I always make it a point to run an event on Street tires. Race tires, for all their lovely stickiness, can also hide a LOT of bad driver habits. Going back to streets for an event that doesn't count towards points is a great reminder to stay solid as a driver to make the most use of the stickier tire setup.

With that being said, If you have never run R compounds before, you treat them much differently than street tires. I would recommend buying a set of V700 Victoracers, sticking them on stock sized rims, and go play in A-Stock if you can, BSP if you have other mods. It will teach you the differences between "street tires" and R compunds and be fairly cheap learning experience. Expect to get beat on and make sure you learn from it so when its time to step up to an A6 or V710, you know EXACTLY what you are doing and where you want to go.

Just IMHO.

-Sean Caron
Ex DSM SM guy.

 

Gotta hate DisASSlusioning!!!

 

That's when you bump to a new class like you are hot **** only to get rubber shoved up it.

 

Just remember, like everyone else is saying, R-comps put you in a different class. A class where they allow a LOT more mods.

If you just want to go faster and don't care about what place you finish in, then by all means, get R-comps.

If I were you, I wouldn't even think about moving to another class until you are consistently top-2. If you jump up to SM and don't seriously upgrade the car and your driving, you will get owned very very badly. It's a BIG money jump to be competitive in SM.

 

Ok, for clarification I am always first or second in my class and always top 10 overall compared to all the cars.

I don't mind moving up, but I am not ready to do major suspension work to my car.

I would like to run stickier tires to improve my lap times.

Thanks

 

how are you single driver cars keeping your tire temps up running the 285's? i can't see using such a wide tire if you can't even get it up to temp and keep it there. whereas a narrower tire that is at the proper operating temp will actually have a better Cf thus more grip...

this is even more apparent at nationals where the two driver cars were considerably faster then the single driver cars where the tires were cooled down during the long wait, while the two driver cars got twice as many runs to keep the temps up.

what other tires could you use, is there a 265x18 with the same sidewall ratio to keep the tire spring rate high?

 

Kevin, it doesn't take long to get an autocross tire up to temp. There's not much time between runs either, so you don't have to worry about keeping it up to temp. You will not be as fast with a smaller race tire than with a 285 on the Evo.

Rio, you can't fully utilize super grippy tires without a proper suspension. You will just overpower whatever suspension you have and waste the tires. I did this all of last year where I had nice V710s but only the stock suspension, and all the grip from the tires killed the suspension dynamics and made me roll all over the place. Also, there are no lap times involved in this discussion unless you're talking about road racing.

 

This is great advice.. you guys are very knowledgeable.

ok, I will buy a set of V700 Kumho Victoracers and use a set of stock BBS wheels.


Thanks

 

actually it does take a while to get a autocross tire up to temp... and the wider it is the longer it takes. thats why our UTA FSAE car ran the narrower hoosier on a 13in rim... we couldn't get the wider tires up to temp fast enough to be quick in all the runs. this is from extensive tire testing in state of the art labs, simulation data , and 20 years of autocross experience i know the situation is different... open wheel versus closed wheel, but the fact of the matter is, physics says it doesn't matter how wide the tire is, if the coefficient of friction is equal given two different width tires, your frictional force will be the same (i.e. same torque to the ground). however, common sense tells us that if you can overcome the shear force the rubber has (i.e. leave black marks everywhere), then a wider tire can benefit you by distrubuting the load, thus more grip from less spin.

so thinking logically, if you go to a skinnier tire, and get it up to operating temp quicker, your runs should be more consistent, with more grip due to having a better coefficient of friction (generally tires friction coefficient increases with temperature until it reaches to high of temps, and begins to fall off again.).

i would be interested in see tire temp comparisons of two driver and single driver cars... as well as temp comparisons of 285 tires and say a 255 or 265 tire... (maybe even a 275 if thats all hoosier makes).

additionally at smaller regional events the time between runs can be very short, whereas events like here in DFW, you have to wait a long time before runs, totally killing your tire temps. nationals is obviously that way as well... two driver cars get a huge advantage of tire temps.

warr, you very well could be right about the wider tire getting up to temp quickly on the evo. i'm just posing this logic to see if anyone has actually tried the narrower tire with success, and actually done some data logging of tire temps to go with it.

 

Take a look at ALL the National level BSP and SM Evos. Every one of them that are at the top run 285's. It is a lot more tire even if they don't get to the same temp as quick as a smaller tire would.
The 265/35/18 is a perfect match to the stock tire in sidewall ratio. The 285/30 is shorter. The problem with the 265/35 is that the only offerings are road course type tires...such as AO48's.

 

A048's are good track day tires. For solo, you need instant grip at ambient temps. You will not get that from the Yokos.

I can tell you that most of the SM cars at nationals had v710's or A6's.

 

Agreed.