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I'm considering getting larger tires for my Rs.

Right now I'm on 215 45 17's. I think the subie would really like to have larger tires.

I know the Jun GC8 has somethink like 235 or 245 tires.

However I'm trying to stick with just rolling or modding the rear fenders and possible removing the plastic trim under the front fenders.

So what i'm asking is who has 225+ tires, their Profile, and what kind of suspention are they rolling on?

thanks in advance
larry
 

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overdeveloped beater
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We run 225-50-16 Hoosiers on stock 98RS wheels and the car is lowered quite a bit. We had to roll the fenders, add longer studs to the rear hubs and add a 1/4" spacer to get the tire to clear the strutbody. Fronts went on with no rubbing except at full lock and full compression (which is minor at worst).

The Hoosiers are substantially wider than a comparable street tire of the same size. 225-40(or 45)-16 would be better. The 50 series gives a diameter taller than our 215-40-17's for street/rain duty.

Your on 17's so 225-40-17 would be most comparable and should work okay.
 

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At stock height you can run 225 width tires fairly easily in front. If the car has been lowered any you will need to roll the front fenders. The rear is another matter. You will probably need to get some spacers, though perhaps not as extreme as the 1/4 inch spacers that Storm and I are running on our respective cars. There is just not enough clearance between the strut body and the tire.

If you want to go wider you are going to have to do some pretty extreme stuff. Probably buy some 45 or lower offset rims, roll front and rear, get spacers for the rear, and almost definately not be able to run anywhere near stock diameter. You would probably have to run something at least 3 or 4 percent smaller overall diameter than stock if you want 235 or wider.

By the way, if it is the same Jun GC8 that I have seen some write ups on, it has a 22b body kit, so the fenders are WAY wider.
 

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Hmmm...

As the '03 Autox season approaches, I am leaning more and more toward DSP (I'm in STS and have considered STX, but R-compounds and a flywheel seem to be calling my name...LOL). If I run in DSP, I was planning to run 205/45-16 Kumho Ecsta V700s.

However, I know Templar has run 225/50-16 Hoosiers on his car with fender lip rolling, inner fender removal and rear spacers and all but the inner fender removal is SP-legal. So I got to checking and the 245/45-16 Kumho Victoracer is just barely wider (and a bit shorter) than the 225/50-16 Hoosier (0.4" wider section width, 0.3" wider tread width, 0.3" smaller diameter). Plus the 245 measurement was on 8" rims (and I'll be running 7" rims), so the width difference should be even less. It does worry me that the minimum wheel width for the 245 is listed as 7.5", though.

So, any ideas whether this tire (245/45-16 Victoracer) would fit on a 99 2.5RS with fender rolling and spacers? (I would run a 225/45-16 if any R-compound maker had one, but they don't so that's why I had planned to go with the 205/45-16 Ecsta. (Of course, Hoosier makes a 215/40-16, but they are MUCH more expensive.))

Then again, in theory a 245/45-16 street tire would be even narrower making STX a possibility...hmmm...
 

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I would run a 225/45-16 if any R-compound maker had one
Kumho makes the Ecsta in 225/50 16. pretty close. that's what i'm going to run next year (with AGX shocks). according to the NW guys, this will fit. i still have my reservations. perhaps those guys have been sniffing too many pine trees but i'll give it a shot. i test fitted the old 225/50 16 victoracers on WRX wheels just to see, and they fit...as long as the car didn't move. it was pretty clear that if you loaded the suspension, it was going to be rub city, especially in the rear. the Ecsta is supposed to be a bit narrower and the extra stiffness from the KYB's should help, but we shall see.
 

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Pine sniffing

http://www.subrew.com/library/kumho_comparo/

As one of those "pine sniffing NW folks" I point you to the above page. It details Chris' experimentation with 245/45-16s and 225/50-16s as well as the differences in shape between the Ecsta and Victoracers.

Since that page was created, I've run the same combination of tires (245s front, 225s rear) on my DSP subie, which is lowered quite a bit. I don't think the fronts would work as well without the camber plates I've got -- they'd hit the fenders pretty badly. I didn't have any issue at all with strut clearance, but they did rub the inner fender liner a bit under full lock.

All that said, I don't think I'll end up using 245s on the front -- I'm running them on 7" wide rims (yes, they fit, but barely), and I think the narrow wheel is providing a less-than-optimum sidewall, because turn-in is for crap. For me, I'm sure running 225/50s all around will be fine. If I were running stock class, like Chris is, I'd go for the 245s, since you can't tweak the rest of the suspension.

Hope that helps, I'm off to sniff some pine trees ;)

Sean
www.subrew.com
 

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overdeveloped beater
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I agree with Sean above. And concur that the fronts of our RS took the 225-50 16 Hoosiers without any complaint or modification (besides camber plates up top). Rears have about 8mm clearance between the strut and tire after the spacer is in. We have skidmarks showing where the whiskers hit it and maybe even sidewall deflection too.

It's too bad that a 16x8 wheel isn't available reasonably. I thought about getting some circle jerk IMCA wheels and redrilling them with our bolt pattern, but decided against it.
 

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Well, I would go to 225/50-16s but, this last season I was running 195/50-15s and 205/50-15s and the difference in acceleration (due to both gearing and weight differences) was very noticeable compared to stock size tires (especially since almost all the local autocross courses are very tight and don't require 3rd gear even with the tiny 195/50-15s!!!).

The 205/45-16 is only barely larger in diameter than the 205/50-15 which is why I'm considering it so much, but I'm wondering whether the extra width of the 225/50-16 would be worth the loss in acceleration of going back to a near-stock diameter. (The 245/45-16 is shorter than the 225/50-16 which I why I even brought that size up at all. Like I posted previously, I'd love a 225 with a 40 or 45 series sidewall, but that simply doesn't exist with 16" R-compounds (quite a few street tire choices in those sizes, though).)
 

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As one of those "pine sniffing NW folks" I point you to the above page.
hehe, yeah, that's the page i was refering too :)

personally, i wouldn't want to go to a shorter rolling diameter. our courses tend to be fairly fast (and on higher levels they're all pretty fast). sometimes i'm already doing 5 shifts on a course! that's more then through a 1/4 mile :lol: there was a guy locally who was running 205/45 kumhos and he had to shift even more than I!
 

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Well, I've picked my setup for next season. I'm going to DSP and I'm most likely going to start the year on a set of used 225/50-16 Victoracers, then when they wear out, I'll know whether that size/tire was a good choice or not...hehe. :)

Shane -- http://www.warpthree.com
DSP 729 -- CCar Region
 

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overdeveloped beater
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www.sourcemotorsports.com
It needs to be updated (severely) but we run 225-45-15 ECSTA V700s for all local events and shorter divisionals. We ran the taller Hoosiers primarily at Topeka and then for long, fast courses. The differences in accelleration and braking between the 45-15's & 50-16's are huge. When we hit the limiter in 2nd running the Hoosiers...I know we're fucking flying! Topeka's courses this year made good use of all that diameter. Sticking with the 225 section gives us enough grip for most any course and no real problems with the car handling the slaloms or quick transitions.

We were still spinning all 4 off the line with the Hoosiers so accelleration isn't hurt that much!
 
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