Thinking about trying STX out next year
 

I'm thinking about giving STX a shot next year. I currently have a '93 miata that I run in STS2. I love the way the car handles but it is just too slow. I need something with more power. I have an '04 GT that is my daily driver.

I've been looking at wheels and tires trying to figure out what I want to use. There is a proposal to allow 9" wide wheels and 265 width tires. Threw the little bit of research I've done so far I've found that in the 18X9 size the wheels are either super heavy or too expensive for me. I've found some 18X8.5 that are both light and reasonably priced. And then there are 17X9 that are quite a bit lighter than the 18's and also reasonably priced. With the 18's I'd run either Yokohama's or Bridgestone's in a 265/35/18, for the 17's it'd be same tire manufacturers but in a 255/40/17 since neither make a 265 in a 17.

I'm leaning towards the 17's for both weight and price. What do you guys think?

heavy 18X9 with 265/35/18 or
Light and narrow 18X8.5 with 265/35/18 or
Light and wide 17X9 but with narrow 255/40/17?

Putting the cart just a little before the horse there.... You have a car that has not been moved to STX, and are shopping for wheels and tires that are not legal yet. :lol:

If you are going to do it, it is worth doing right, 18X9 (light ones) with 265s. The RX-8 will need all the help it can get. Assuming that both it and the wheel/tire deal even happen. :uhh:

More like thinking about it and planning incase the rule change happens and I decide to go that route.

Thanks for the input, though so far the light 18X9's I've found are out of my budget. Maybe I can find something if I keep looking though.

BBS RE 18X9 20.9lbs $449 @ Tirerack.

More here: http://www.1010tires.com/wheelsearch.asp?submit=yes

The enkei RPO3 comes in an 18X9 +40 @ 21lbs.
RPF1 18X9 +35 @ 18.5 lbs

FYI, when Vorshlag (Terry Fair) was doing their best to campaign a E36 M3 in STU they found that the 255/40/17 Neova was pretty much as wide as the 265/35/18 RE01R.

I'm with Jason, if you're going to do it right, it needs to be the 265 Yok, but the 255 would probably be fine for local competition. Look through Team's STU thread for all the good info.

If all the changes go through the RX-8 looks like it would be a fun STX car.

The Dunlops are a great tire as well, not to mention the Toyos and the soon to arrive in 2012 Kumhos.

There is a part of me that wants to try STX, but at this point the cost to run STX seems pretty darn high considering how relatively inexpensive it is to run BS.

I have seen the Kumho XS in action. Two of our locals have them, 15s and 16s, have both been run on an STS Civic with good results.

Hmmm STX. Spend more money to go slower. :icon_no2:

Way out of my budget


I didn't know that that low of an offset would work. But if it does that might open up some more options. I just did a price quote on tirerack for the RPF1's in both 18X9 and 17X9 with yokohama's. $1952.00 for the 17's, this is right at the top of what I want to spend for wheels and tires and these are what I was planning on getting if I went the 17" in route. $2584 for the 18's, more than I want to spend. But I can still look for cheaper wheels and maybe I'll adjust the wheel and tire budget after figuring out what everything else will cost. But initially I would say they are out of my budget.

I think I'm still leaning towards the 17's but I'm not dead set on it. We'll see.

The next thing I need to figure out is which coil overs I want to get and what spring rates I want to use. I've got Tein flex's on my miata and really like them, so right now I'm leaning towards the Tein mono flex's. The original spring rates on them were terrible, I tried a few different setups, currently I'm on 12k front and 9k rear, ( 672lbs/in front, 504lbs/in rear ). This gives me a bounce frequency of 2.54hz front and 2.77hz rear, this is way too stiff for daily driving. But the setup I had prior I think was a great compromise between track and daily driving, 9k front and 7k rear ( 504lbs/in front, 392lbs/in rear ). This gave me a bounce frequency of 2.20 front and 2.44 rear, I think this is were I want to start with my RX8. But I'm missing a big piece of the puzzle, I don't know what the motion ratios are. I tried searching and couldn't find them, I don't have the time to measure them myself right now. So if some one knows them and would like to share I'd really appreciate it.

Well since we're talking about stuff out of your budget, I'd just like to say that WedsSport has a 18x9 50mm offset TC105N that's 17 pounds.

I really don't think that the Yoks are worth 80 bucks more per corner than the Dunlops. That saves you about 320 bucks.

The data we have looked at in our region shows that the Star Specs pull similar g's in the corners as the r tires.

On the same car? What type of surface does your region run on? How fresh were the dot-R tires?

Agreed. The two tires are very similar and my WRX/STI/Evo buddies love the new Dunlop Star Specs.

Looking at the specs on Tirerack in a 265/35/18 size, both tires weigh 28lbs and have a 25.3" overall diamater. The Dunlops also have 0.1" wider section width than the Yoks when measured on similar 9.5" width rims.

Not the same car or same driver, STX WRX vs. BS RX8. Flame away because its deserved as I should have identified this in the previous post.

Not sure what would be expected in typical g's for a well-setup (tour winning) STX WRX versus the typical BS RX8. FWIW, we've seen similar peak and just slightly lower sustained g's on both concrete and asphalt with the Dunlop WRX versus both hoosiers/kumhos (fresh) on the RX8. In fact, my Hoosiers often look worse, but that is likely driver related. Also for full disclosure, these are MaxQ numbers not accelerometer readings.

It is not a true scientific test, but I was shocked to see how close they were. The times run by the car in question have come down a good second per 60 second course as well since going to the Dunlops from Hankook (admittedly not a great tire).

This might all be for not, because it would be best to have a test on the same day, same surface, same driver, same car....

Hopefully, grm will have a better measure of the new batch of st tires soon.

Maybe Chris at tirerack would know if this is in the works.

I did find this that essentially indicates that the Star Spec is a wash with the Yoks in the dry and better in the rain.

http://www.tirerack.com/tires/tests/...y.jsp?ttid=107

^ Gotcha. What kinda sustained lateral g's was the STX WRX seeing?

On "fresh" V710's, my co-driver and I see about 1.2g's on the smooth Fedex asphalt (MaxQ numbers). Are you approaching this number when you drive your BS RX-8 on asphalt?

When I first switched to this car from my former DS WRX, I never saw lateral g numbers above 1.05-1.1g's until I got it into my head that the RX-8 could corner much faster than my former car. :)

Is there a particular reason for 18" wheel? Why not go with a relatively cheaper (in wheel and tire prices) 17X9.5 or 17X10? I know for a fact a 17X9.5 +45 offset wheel fits with a 275/40/17 or 255/40/17.

I would guess because the wheel sizes you listed are not legal via the current proposal. Limit in the proposal is a 9" wide wheel and 265 tire. I doubt within the same brand/model tire you will see a 255-17 that is wider than a 265-18.

I currently run my RX-8 in STU. I've run cars in both stock classes on r-comps and ST classes on street tires. Even though the RX-8 is the current favorite in BS, I went with STU for a couple reasons, but mainly one big one. I can't stomach throwing away $1200 on a set of tires that will last, in the end, about an hour or two. The thousand-dollar mark put it over the edge, for me. That's just me - I totally understand that to some people that's cool and they'll pay to play. I just don't want to, and I'm not thrilled about the idea of relying on finding used tires.

I would rather spend the money on parts I can keep.

Besides that, I don't have a lot of practical experience setting a car up. I've read some books and I understand some stuff in theory, but I want to have the experience of making changes to a car and feeling the results.

In 18-inch sizes, competitive street tires, it turns out, are just as expensive as r-comps. That's the punch line. So I run 17" wheels with 275 Azenis. I will likely do the same next year, but with some lighter wheels. I'll probably have to settle for 255s instead of the possible 265 maximum width, since I can't find 265/17s. That is, of course, assuming the changes happen.

Am I paying more, in the end, to go slower? Yeah, but I'm learning new stuff, too. That's worth it to me.

it made them feel better to say it, plus it actually fit in the well where the 265 did not :mdrmed:

Very true and I've thought about that. I don't have any experience with these tires, but from what I've heard they have ton's of grip but feel like crap. Feel is very important to me. On my miata I run the Bridgestones and love how they feel. Prior to them I was on azenis's and could never feel what the car was doing.

Says the guy who's considering not keeping said parts :lol:

You going to Parkland this weekend?

gotta call BS on Dunlop SS pulling similar Gs to a Hoosier A6 :rolleyes:

I hope that the STX proposal goes through for the RX8 but I'm not sure that the 9"/265 proposal should happen at the same time. I'd like to be able to run a 9"/265 combo but I think that it may be possible for the RX8 on the 8"/245 combo to keep up with the current crop of STX cars. If we can't keep up with the E36's on 245's I don't see any advantage coming from the 265's. Although, the 265's could knock out all those STS guys on 8" wheels ;) We just have to hope no one ends up making a 265/35R15 or the '89Si will really dominate STX :eek:

My hope if for the 8"/245 setup. I've been looking at the 15.6lb 17x8 ET45 RPF1's with 245/40R17 Star Spec's for $1548 from TTR. Second on my list is the closeout 15.4lb 17x8 ET45 Kosei K1 TS wheels with the same Dunlops for $1348 (approx the same cost of my last set of 285 A6's by themselves).

Check the registration list. :p

As for the parts, Stance is treating me real well so far. :)

I just looked at the data again now that I have opened myself up to scrutiny, and it is amazingly close with peak g's being higher for the Dunlops.

Here are some of the data on concrete.

If you're talking about Terry, I explicitly said that he was comparing the 17" Yok to the 18" B-stone. And yes, the 265s didn't fit well under those skinny E36 fenders.