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Discussion Starter · #1 ·
Maybe not new but I see on Evom that lots of guys are starting to use 1/2 inch wider wheels up front to increase track,steering input & decrease understeer.Must work since a lot of JDM time attack cars like the Cyber Evo are doing this with great results.Comments?
 

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I for one think people are retarted for running wider wheels up front on the street. The track is another matter, if its like 315 front and 305 in the rear i can see that in racing, if its anymore than that, then i have to wonder other then front grip what the tires are actually doing.

You can make any car rotate, that you can do with neat little suspension tricks, so there is no real need to run wider tires up front.
 

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Discussion Starter · #3 ·
Wheels not tires.They are using same size tires front/rear so not to damage diffs.
 

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EricK said:
Wheels not tires.They are using same size tires front/rear so not to damage diffs.
same effect. As long as the diameter of the tire is the same front and back the diffs should not care if the front is wider or not.

A wider wheel with the same tire simply adds more contact patch on the road. Its something like .3" for every .5" wheel bigger or something like that. Either way, wider wheel, wider tire, they both add contact patch.

so are they like 9.5's up front? or how do they do it?
 

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This isn't a bad idea for the big money guys but for a budget racer who needs to get 110 runs (autox) out of his V710s this doesn't make much sense. You'd have to dismount the tire to rotate them! :eek:

the high dollar guys are running any where between 9.5-10" front and 8.5-9.5" rear in either 1" or .5" difference between the two.

The only subie i've seen (on the boards) with that is the EAuto STi with 17x9 +43mm CE28Ns in the front and 17x8.5 +50mm CE28Ns in the rear. This is a really slick setup b/c it keeps the rear under the fender and the front is wider and since you usually run -2.5 or so camber in the front for autox/track the fronts are under the fender as well.

there is a local EVO running 17x10 +35mm front and 17x9 +35mm rear with 275/40 V710s all the way around.

of course he has one set of each which he alternates between events, crazy $$.

and this is no new trend, the "grip" racers have been doing it for awhile now.

the AWD guys have just starting doing it as well.
 

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T3h_Clap said:
This isn't a bad idea for the big money guys but for a budget racer who needs to get 110 runs (autox) out of his V710s this doesn't make much sense. You'd have to dismount the tire to rotate them! :eek:

the high dollar guys are running any where between 9.5-10" front and 8.5-9.5" rear in either 1" or .5" difference between the two.

The only subie i've seen (on the boards) with that is the EAuto STi with 17x9 +43mm CE28Ns in the front and 17x8.5 +50mm CE28Ns in the rear. This is a really slick setup b/c it keeps the rear under the fender and the front is wider and since you usually run -2.5 or so camber in the front for autox/track the fronts are under the fender as well.

there is a local EVO running 17x10 +35mm front and 17x9 +35mm rear with 275/40 V710s all the way around.

of course he has one set of each which he alternates between events, crazy $$.

and this is no new trend, the "grip" racers have been doing it for awhile now.

the AWD guys have just starting doing it as well.
+9435213274

your kung fu is strong 'clap'.
 

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I've read of people buying adjustable lateral links for the rear and pushing the wheels in a bit for what would seem to have a similar effect.
 

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for increasing track?

I guess decreasing the rear is similar to widening the front.
 

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T3h_Clap said:
for increasing track?

I guess decreasing the rear is similar to widening the front.
The effect should be similar, although I'd rather widen the front as much as possible before going through the trouble to decrease the rear.
 

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spazegun2213 said:
I for one think people are retarted for running wider wheels up front on the street. The track is another matter, if its like 315 front and 305 in the rear i can see that in racing, if its anymore than that, then i have to wonder other then front grip what the tires are actually doing.

You can make any car rotate, that you can do with neat little suspension tricks, so there is no real need to run wider tires up front.
I disagree.

Suspension tricks can get you the handling bias you want, but different sized tires (and wheels) can help you get your tire temperatures balanced out. If you've ever run high-temp tires in cold weather, you know how important it is that your tires heat up evenly. Wider tires generally operate at lower slip angles, so they generate less heat.

I had a rude awakening in a FWD car when I realized I couldn't get my fat rear tires heated up while the fronts stayed plenty warm. Oversteer doesn't even really describe it, I had to keep the car at WOT mid-turn to prevent a spin. Braking had to be done perfectly straight. It felt like my rear tires were on plastic trays. I haven't yet had the opportunity to repeat this in the STI, but being a front-heavy car, I'm sure it too heats the front tires up prior to the rear, though to a lesser degree than a FWD car.

Tire temps can be manipulated a little bit with tire pressures. Running lower pressures will cause them to heat up more. However, running a lower tire pressure changes the rolling radius of your tire very slightly, so I don't see how this is any better for an AWD car than running a wider tire (so long as it's very close in diameter). I think running wider tires up front is a great idea, but only for dedicated track cars. Another solution is to run different tire compounds front and rear. Ever see an autocrosser run Azenis RT-615's front and RT-215's rear?

However, I wouldn't consider any of this on a street car, as you lose the ability to rotate your tires.
 

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i've seen someone run R-comps in the front (RA-1s) and Street tires in the rear.

it was a scion, but he still had issues very similar to what you described.
 

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stretch said:
I disagree.

Suspension tricks can get you the handling bias you want, but different sized tires (and wheels) can help you get your tire temperatures balanced out. If you've ever run high-temp tires in cold weather, you know how important it is that your tires heat up evenly. Wider tires generally operate at lower slip angles, so they generate less heat.

I had a rude awakening in a FWD car when I realized I couldn't get my fat rear tires heated up while the fronts stayed plenty warm. Oversteer doesn't even really describe it, I had to keep the car at WOT mid-turn to prevent a spin. Braking had to be done perfectly straight. It felt like my rear tires were on plastic trays. I haven't yet had the opportunity to repeat this in the STI, but being a front-heavy car, I'm sure it too heats the front tires up prior to the rear, though to a lesser degree than a FWD car.

Tire temps can be manipulated a little bit with tire pressures. Running lower pressures will cause them to heat up more. However, running a lower tire pressure changes the rolling radius of your tire very slightly, so I don't see how this is any better for an AWD car than running a wider tire (so long as it's very close in diameter). I think running wider tires up front is a great idea, but only for dedicated track cars. Another solution is to run different tire compounds front and rear. Ever see an autocrosser run Azenis RT-615's front and RT-215's rear?

However, I wouldn't consider any of this on a street car, as you lose the ability to rotate your tires.
touche, i agree with you here.

however, I'm strictly talking about AWD cars. I have NO expierence with FWD cars, but i can see your point.

the one thing i want to point out is these are high powered time attack cars, with a slim set of rules (if any) attached to what they can do. I have yet to hear of a T2 team have a [bad] problem getting their sti's or evo's to rotate. Sure they are awd and even in their confined set of rules they can make their cars top the podiums.

Again, i go back to suspension tricks and driving styles (Trail braking amoung other things) to help comensate for the understeer that our cars have.

However, i do see why they would do it on the time attack cars. But i still stand by that its useless on the street.
 

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Doesnt the Showcase BSP evo (andy leibers, spelling?) have a setup like this, as well as Mark Daddio's SM evo?

I would be interested what joel in his BSP sti has thought about a "staggered" setup.
 

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Crystalhelix is running 305s up front with 275s in the rear both on 17x10s.
 

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What if you used the same size wheel but different offsets on the front? Just like increasing front track. Has this been done?
 

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flatthump said:
What if you used the same size wheel but different offsets on the front? Just like increasing front track. Has this been done?
you might as well run wider wheels too, since due to the offset you wont be able to rotate the wheels front to back.

running a spacer up front is the only way to achive what you're saying and still be able to rotate the wheels/tires
 

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I rotate my tires a little differently. I haave them switched from rim to rim so I can use the inside rears as my outside front. That way I have a relatively 'fresh' outside tread forr the fronts. That can be done with the Advan AD07's, and my friend does it at his shop for free(orr a couple beers)

Wheel spacers scare me.
 

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flatthump said:
I rotate my tires a little differently. I haave them switched from rim to rim so I can use the inside rears as my outside front. That way I have a relatively 'fresh' outside tread forr the fronts. That can be done with the Advan AD07's, and my friend does it at his shop for free(orr a couple beers)
sure that's not a terrible Idea, but if you do that too early on a set of R-comps you'll eat right through them :(


flatthump said:
Wheel spacers scare me.


I aint scurrred! :lol:
 

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T3h_Clap said:
sure that's not a terrible Idea, but if you do that too early on a set of R-comps you'll eat right through them :(
Ill keep that in mind, I cant afford tham at the moment:p
 
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