Well, I've finally got enough money to buy a set of decent tires... now it's the decision of which ones/what size..

My wheels are 17x8- (the only thing that will fit over my brakes)

I'm currently running 235/45/17 on them, and they're very close to the wheel wells with Kumho 712. they tend to run a bit wider at the tread than some of the others I've run- like my Azenis ST-115 and Sumitomo HTRZ II..

After looking at sizes on the Azenis sport, they have 225/45/17 and 245/45/17. the 245 would of course be preferred, but they MIGHT rub in the back. am I going to loose much traction between the 225 and 245?


The Kumho Ecsta MX comes in the same size (235/45/17) that I've been using, but it's a hair more $ than the Azenis and I've heard the performance just isn't there compared to the Azenis.

OR, go to victoracer V700 for another $25/tire.. They come in both the 225/45 and 245/45...

Azenis, $125/tire 225 or 245
Ecsta MX, $140/tire, 225, 235, or 245
Victo V700, $165/tire, 225 or 245

Most of the use these tires will see is AutoX duty on old gravelly asphalt, but I will also be running at Texas World Speedway (concrete??) and Motorsport Ranch (concrete) on occasion. maybe 3-4 times a year. Whichever tire I choose will have to stand up to that kind of use.

recommendations?

 

Probably exclude the Azenis. Hot climate in TX combined with concrete will easily overheat em on auto-x let alone open track. They go away above like 130-140deg.

It seems you're looking at both street and race rubber. Why? If you can run race rubber in your auto-x class then by all means go that route. That opens up even more choices than just the V700.

 

much as i hate to say it that is probly 100% correct. im still getting the 245 ones for my car when i get the money, but i drive nice in autocross.. nice to my tires anyway. if i hear a scrubbing/spinning tire it means im doing something wrong or im flooring it (me hates open diff). i have not put the dynasty on a road course yet and i may never.. and i have other cars that i may be more willing to, so i still think that azenis are the ones for me.

but im wondering too, if you're considering race rubber at ALL, WHY are you still considering street tires? if you have the option of race tires, theres no good reason not to that i can think of.

 

You gotta choose race or street tires first man. Why in the world would you settle for azenis or some other street tire when you are considering a real race tire.

 

The reasons I was hoping to stay with a street tire were more for auto X classing.. I'm already in STU, where I'm up against STi, EVO, and even a Porsche GT3... way outgunned. going to race rubber will throw me into a prepared or modified class (not sure which class yet. I'll find out next auto x!)

I was also worried about the cost.- the hoosies were running $200+ a tire, and don't last very long.

Soooo, I poked around on one of the local auto X forums and ran across a guy that has a contact on tires..

Ended up picking up those guys for a damn good price. new wheels should be here today or tomorrow.

 

Contrats on the tires. Curious what's pushing you into STU? Are you running a blower of some type? DSP would be a fit between the ST classes and Prepped.

 

With these tires, I'm actually bumped up to SM.. I'm gonna get fooked.

the big mods:
aluminum flywheel
custom coilovers (GC-type)
13" brakes
subframe connectors (bumps you to prepared.) w/ lateral bracing (prohibited in prepared class).
all rear suspension bushings replaced with heim joints

the last two mods are the worst of them, which were still allowed in STU- since it's pretty much anything goes, as long as you're on street tires....

but now that I'm running R comps, I have to go to SM.


FYI...


Yummy.
They're mounted and balanced, but I didn't have a chance to get them on the car and get a heat cycle in them yet.

 

me so jealous

 

I've always liked those rims, I want to see some pics of them on your car

great choice Matt

 

Great Choice! You will love the RA1s. I am on my 2nd set. They wear real well, hold up to heat cycles, and stick pretty damn good.

They tend to squirm at full tread, and will be greasy until after the first heat cycle. If you can give um one good solid cycle and them take them off the car for a few days, that will really help them last. They are very predictable and give fair warning before letting go.

As the heat cycles add up they loose some grip (especially when cold). I got about 15 track days, about 70 heat cycles on my first set at still had some tire left, but I was looking at two days of open lapping so I got a new set.

 

Here's a few shots of them on the car...



More pics here:
http://www.mattblehm.com/pics/car/wheels/track_wheels/

I got them on the car (obviously) and ran them for about 75 miles on the street. 90% of it was just straight highway stuff, but I took a few FUN corners with them. WAY stickier than my street tires! on my old tires, I can usually take a certain corner behind the house at 45 using both lanes on both ends of the corner (don't worry, I can see the far end of the oncoming road before I even have to brake to turn in)... anyway, I took it at 45 and had to coutner steer to keep from smacking the curb at the inside of the corner! I went back around and took it again at 55 and still only needed one lane of concrete coming off the corner. I can probably take that same corner at 65, compared to 45 on my street tires. WOW!

I figured after a few miles of me scrweing around on them, they'd gotten a decent heat cycle on them, so they're back off the car and hiding under plastic in the garage. when I pulled them off, they still had the paint stripes and most of the knobbies on them from the factory, so I hardly wore them at all.


so Amax935, what kind of pressures are you using on them? The place I bought them from recommended starting at 40-42 psi up front and go 2 lower in back, but that's where I autoX my street tires.. seems awfully high for tires like these.
my little test drive earlier was at 30psi on all four, and I was just barely going past the edge of where I should be rolling over on the sidewalls on the corners. I'm thinking 32-35 is a better starting point, but I'd like your input on them first.

 

the fnrc come in 17x8? i had no idea.
i'm still debating azenis vs MX... i think it'll come down to price.
Jae

 

I have been targeting 34 Front and 38 Rear (Hot). 911s are more prone to oversteer, I'm not sure about the logic of running higher psi in the back, but it is common practice. My friends with 944s run 36 Front and rear hot.

There is a pretty large toyo supplier on the east coast that claims that 38 psi is the magic number for RA1s. 40 - 42 seems a little high. These are track pressures, I don't know about autocross cause I never did it.

 

I've always heard that RA-1s are one of the less sticky R comp, but last FOREVER. They are still a huge jump up from any street tire. They are likely what I'm going to get when I have the money to get Rs after I get this turbo installed, if ever.

 

instead of making a new thread, I'll dig up this one...

Matt, so how did you end up liking the RA-1s?

I'm at the point of (in)decision between Azenis 615's and going to something more "serious". I've heard that the 615's solved the 215's problems with getting oily in the heat, but can anyone confirm that?

My only worries about R-comps are:
1. not heating up enough for the short autocrosses around here,
2. can I get a season out of them?
3. aren't r-comps fairly unpredictable, regarding breaking free at the high end of grip?

also, can someone explain the heat cycling?

I plan on mostly autocross this season, with possibly 1 or 2 road courses...

 

The new 615 Azenis still get greasy, just a bit later than the 215. Ref the Aug GRM tire test. For a auto-x with combo cold & hot season's they're perfect as you can spray em down in summer. Just be careful on road courses if it's hot and keep the temps down below 140ish if you can.

R-comps will easily last 100+ runs if taken care of meaning lots of neg camber and some sort of heat cycling before using. They will require a first run to get up to temp and in 50 or below temps they'll really be slippery.
http://www.tirerack.com/tires/tirete....jsp?techid=66

If I has 17" rims and was in your situation I'd probably get the Yoko A032R's, Kumho V700, Toyo RA1, or the Kumho MX. A set of shaved MX would be less than $600 and they'd handle track heat just fine.

 

Thanks Brian, I was hoping you'd weigh in. My focus is really autocross, as I don't have the time and money to do much road course racing (plus, the closest one is a few hours away)...I may go up for a couple track days, but only for fun and not in a competitive manner...aka I probably wouldn't push it all that much.

For autocross, I am running with a few different clubs and want to be as competitive as possible.

Would you still go with the r-comps even with autocross being the main focus? Keep in mind the CDC events are pretty short courses (30-40 secs), and the SCCA events are longer (40-60 secs)....both CDC and SCCA run pretty much all year, so they need to be good tires for 50degree days and 90 degree days. I prefer a tire focused 98% on autocross...so would the Azenis be a better choice? Also, who sells shaved Azenis? Edgeracing has great prices, but no mention of shaving .....

 

After doing some reading, those Kumho MX are looking like what I'm looking for.....I wonder if shaving them would be a good idea, and if tire rack would do it?

 

you got a nice red third gen with new tires=me no care
Just kidding great looking car matt. Those tires look nice and the rims too. bet you going to love them.

 

The MX's absolutely need shaving. Quoted from GRM "The trick with the Ecsta MX is that you've simply got to shave the tire down to 4/32 or below for maximum grip. It's performance appears to be inversely proportional to the amount of tread that remains. The lower it is, the faster the tire becomes until you're left with just the cords hanging out...the hotter the tire got, the better it performed" Yes, TR will shave for like $15-$25 additional.

 

good luck with those...let me know how they perform...i need a new set of tires for auto-x this season since i again will be bumped to SM as well....i was thinking MXs or Azenis...but i cant decide

 

RA-1's are great...everyone I talk to about them gives a big thumbs up...I know...I run them at autoX and when I road race! they do have a sweet spot in temperature where they grip the best...make sure you properly heat cycle them so they last longer and also did you get them shaved or are you just going to run them at full depth for a while b4 you hit the track...I only say this b/c when I run non-shaved Ra-1's they tend to chunk since they squirm at their full tread depth a lot...(on the plus side though, they really grip well in wet racing at full tread depth!)...but they won't compete with full race slicks such as hoosiers in my experiences, but they will end up gripping nearly as well at low tread depths (ie. 4-2/32) and they will last a whole lot longer....

I have driven some cars and ridden some cars with every r-compound imagineable...they really didn't make me wish I didn't buy the ra-1's....mine seem to have just as good break-away characteristics, feel, and much better wear than the best of them...and trade up very little grip IMO!

 

everyone here swears by the Azenis...MXs are another popular choice...but right now edgeracing.com has Azenis 615s for like 89 a piece

 

biggest problem with edgeracing (where I buy my street tires) is that they cannot shave tires (I've checked).

I got my new Hankook Z212s from frisbyrace, who can shave them and has similar prices. The Kooks are similar in performance to the 615s and MXs for even less $$....

btw, "everyone here" - everyone where?

 

I forget who but someone won the national STS class i believe in a civic, with shaved falken FK451s, look into it a cheaper option then shaved MXs.