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  • Teqnyck

    Nov. 3, 2010 7:46 p.m. Teqnyck New Reader

    So the situation is this. I have a little project that I'm working on, and the goal is to be more than the sum of all the parts. I run with a group of people who are very fast, I'm talking a race prepped SRT-4, Lan Evo MR, a widened S2000, all of them with big rubber. The S2000 is of particular interest to me, partially because it is the same weight as my car, and partially because I'm very competitive And as a bonus in this scheme, the S2k is on 275/35-18 Direzza Star Specs.

    My plan was to run a Ventus RS3 tire on some of these http://949racing.com/15x86ulblack.aspx 225/50-15 sized. I'm concerned that a car that handles as well as the Honda roadster which has as much rubber under it as this one does would be a very hard target to shoot for when I have 2in skinnier tires than it does. Do you guys that should be a concern of mine? It's not much, but it's still something.

    If I were to do anything bigger, I'd probably go with a set of these: http://www.xxrwheels.com/sportmax_962.shtml# with some 255 or 275 series tires. Going bigger also means that I'd have to do some body mod. Basically I'd have to cut the E36 M3 out of my fenders and find a flare that is, I'm guessing about 4in wide. Who knows how else tires that big would interfere with my body panels, I don't really know.

    It's now up to you, fellow GRMers, to talk me out of doing something stupid. By the way, all of this is going on my '90 Mazda Protege AWD, 2600lbs and 350whp. Come on fellas, lay some knowledge on me!

  • Appleseed

    Nov. 3, 2010 8:23 p.m. Appleseed SuperDork

    Doesn't bad scrub radii mess with AWD cars? Too much offset might lead to torque steer. Be careful.

  • snipes

    Nov. 3, 2010 9:27 p.m. snipes Reader

    I know that there are smarter people here than me, but I am thinking; with 350hp it seems a lot harder to over tire the car. If we are talking autoX and 350hp then it will be darn hard to over tire the car (so no Texas Mile). In autoX it will come down to keeping the tire flat on the ground. I see lots of Porsche 911 at the shop that look cool, but there is 2" of tire that looks almost new when the other side of the tire is on its belts. I guess it is a geometric question like shoot a rifle long range. A little off at 100yards is fine but that same amount at 300 yards is way off. How even is your tire ware now?

  • patgizz

    Nov. 3, 2010 10:00 p.m. patgizz SuperDork

    coming from a guy with a car that has 275/40/17 up front and 315/35/17 rears, you can never have enough tire.

  • doc_speeder

    Nov. 3, 2010 11:22 p.m. doc_speeder Reader

    What kind of racing are we talking about anyway?

  • Teqnyck

    Nov. 3, 2010 11:54 p.m. Teqnyck Reader

    some autox, but track days mostly.

  • DILYSI Dave

    Nov. 4, 2010 6:21 a.m. DILYSI Dave SuperDork

    No such thing as too much tire.

  • Dwayne Elizondo Mountain Dew Herbert Camacho

    Nov. 4, 2010 7:43 a.m. Dwayne Elizondo Mountain Dew Herbert Camacho SuperDork

    I have a set of 275/40r17s for the Beetle. Its a 2.0L car.

  • Nov. 4, 2010 8:40 a.m. mndsm Dork

    Teqnyck wrote:

    So the situation is this. I have a little project that I'm working on, and the goal is to be more than the sum of all the parts. I run with a group of people who are very fast, I'm talking a race prepped SRT-4, Lan Evo MR, a widened S2000, all of them with big rubber. The S2000 is of particular interest to me, partially because it is the same weight as my car, and partially because I'm very competitive And as a bonus in this scheme, the S2k is on 275/40-17 BFG g-force T/As.

    My plan was to run a Ventus RS3 tire on some of these http://949racing.com/15x86ulblack.aspx 225/50-15 sized. I'm concerned that a car that handles as well as the Honda roadster which has as much rubber under it as this one does would be a very hard target to shoot for when I have 2in skinnier tires than it does. Do you guys that should be a concern of mine? It's not much, but it's still something.

    If I were to do anything bigger, I'd probably go with a set of these: http://www.xxrwheels.com/sportmax_962.shtml# with some 255 or 275 series tires. Going bigger also means that I'd have to do some body mod. Basically I'd have to cut the E36 M3 out of my fenders and find a flare that is, I'm guessing about 4in wide. Who knows how else tires that big would interfere with my body panels, I don't really know.

    It's now up to you, fellow GRMers, to talk me out of doing something stupid. By the way, all of this is going on my '90 Mazda Protege AWD, 2600lbs and 350whp. Come on fellas, lay some knowledge on me!

    I can't help you. I have 245/17 Z1 Star Specs under my DD ms3, and I'm trying to figure out how to go wider. I may take a sawzall to the fenders one of these days.

  • rl48mini

    Nov. 4, 2010 8:55 a.m. rl48mini New Reader

    and those 6UL's are available in a 9" width...

  • 93celicaGT2

    Nov. 4, 2010 8:58 a.m. 93celicaGT2 SuperDork

    I'm with Dave. No such thing as too much tire.

    I used to think that my Celica is over-tired. Now i'm trying to figure out how to cram more under it. I know i can fit 285s up front.

  • Gimp

    Nov. 4, 2010 9:01 a.m. Gimp Dork

    Teqnyck wrote:

    And as a bonus in this scheme, the S2k is on 275/40-17 BFG g-force T/As.

    Seriously? Some 175 V710s would probably have more grip than those rocks.

  • 2002maniac

    Nov. 4, 2010 9:25 a.m. 2002maniac HalfDork

    Yea, wider street tires are not the answer. Get some 225 R-comps and smoke them all.

  • Tom Heath

    Nov. 4, 2010 10:09 a.m. Tom Heath Webmaster

    R-Comps versus street tires? Sounds like a good idea for an article.

    I'm glad we've got one available on the subject.

  • Jay_W

    Nov. 4, 2010 11:00 a.m. Jay_W HalfDork

    I should prolly go check on clubprotege.com, but what are you doing to the rest of the drivetrain? Cuz several of mine have told me that ~2-350 whp does not a happy awd mazda box make.

  • Nov. 4, 2010 11:08 a.m. triumph5 HalfDork

    Shortened wheel bearing life with really wider than stock OE tires? Or is this only a problem if the wheel offset is changed by a large factor?

  • 93celicaGT2

    Nov. 4, 2010 11:37 a.m. 93celicaGT2 SuperDork

    There's a purple BG Protege that placed at Nationals in FSP and he was running some VERY wide rubber for that chassis. He's on ClubProtege, might want to track him down and see what he says.

  • Teqnyck

    Nov. 4, 2010 12:13 p.m. Teqnyck Reader

    I'm on clubprotege some, but I get a lot of negativity from that site so I'm not on it much.

    Jay, I've heard all the horror stories, even yours, but I've got a spare GTX tranny in the garage and I just have to see for myself how far I can push the stock trans. I've got a plan for that too should I be so unfortunate as to break a box. Part of me has thought that maybe I should go with smaller rubber to add less stress to the already stressed trans, but in my hunt for speed, I just don't quite know which way to go.

    Thanks for the info guys. I'm leaning towards bigger is better. Who's got that link for universal box flares??

  • Nov. 4, 2010 12:16 p.m. mndsm Dork

    triumph5 wrote:

    Shortened wheel bearing life with really wider than stock OE tires? Or is this only a problem if the wheel offset is changed by a large factor?

    More of a problem if the wheel is all offset goofy. My wheels are actually closer to centered on the wheel bearings, and they're two inches wider than stock.

  • evildky

    Nov. 4, 2010 2:55 p.m. evildky Dork

    DILYSI Dave wrote:

    No such thing as too much tire.

    ...just too little power

  • Matt B

    Nov. 4, 2010 3:14 p.m. Matt B HalfDork

    Have you measured your clearance yet? Advice from those who have gone before you is great, but knowing the limitations based on your car's ride height would be helpful. From there you could calculate your own widths and offset/backspacing based on what body mods you were willing (or not) to do.

    More than a couple of (big) stock spring perches have gotten in the way of wider tires. Switching to a 2.5"OD spring with weld on perches (like Ground Control) can free up some room in there. Not sure what the older proteges are equipped with, but I thought it was worth a mention.

  • kevlarcorolla

    Nov. 4, 2010 6:23 p.m. kevlarcorolla New Reader

    If you can't get a wide tire up to temp than I would say thats too much tire,from my experince I'll take a narrower tire at proper temp than a cold wide tire any day.

  • amg_rx7

    Nov. 4, 2010 6:44 p.m. amg_rx7 HalfDork

    kevlarcorolla wrote:

    If you can't get a wide tire up to temp than I would say thats too much tire,from my experince I'll take a narrower tire at proper temp than a cold wide tire any day.

    I agree. There is such a thing as too much tire.

    350 isn't all that much. My RX7 is at that level at 2800lbs wet and my 255s are more than enough to keep up on track. Bigger wheels and tires = more unsprung weight, slower transitions and more drivetrain weight for the engine to power. You need to be able to make use of all that rubber.

  • Teqnyck

    Nov. 7, 2010 12:10 p.m. Teqnyck Reader

    I'll have to put more thought into this next year. For the time being, I'm probably just gonna get some 205/15s and enjoy the powerslides.

 
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