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225/45/17 or 235/45/17 Tyres a good option?

Old 02-21-2014, 07:22 AM
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Look at the monster truck ride height. Thats how he handled the loss of bump travel. I doubt he could get near steering lock, but even with the manual rack I never put in more than 1.5 turns on course. Wait till you see the abortion JoeFis racing is running this year, 275-15s front 275-17s rear.
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Old 02-21-2014, 02:24 PM
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Originally Posted by Leafy
Look at the monster truck ride height. Thats how he handled the loss of bump travel. I doubt he could get near steering lock, but even with the manual rack I never put in more than 1.5 turns on course. Wait till you see the abortion JoeFis racing is running this year, 275-15s front 275-17s rear.
Seems like even the raising the ride height at the sill seam weld by 4" over what I run to maintain some bump travel the front tires would still crash into the sill area by the firewall with more than about 15 degrees of wheel cut. Has me wondering if A-arms to move the front wheels forward by about an inch were used. The wheel openings are completely not stock and the body work looks amazing.

Somehow they made the compromises work as I don’t think it is a slow car. Not sure it’s the best way to go however.
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Old 02-21-2014, 02:31 PM
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Oh yeah, certainly not slow, both drivers beat me, their time gap was bigger on the POWAHHHHHH course than the technical course though. And there's a ton of money in the car, there's an efr under the hood if I remember right from impound. Remember he has an inch that he can hammer out in the sill area to gain more clearance before he's illegal, I think he can get enough steering lock to be fine on most national size courses.
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Old 02-21-2014, 04:14 PM
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Anyone ever measure their lower control arm (rear) angle in addition to seam height in order to see if your suspension is at the optimum angle? Speaking of which, what's the optimum angle? 0?
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Old 02-21-2014, 04:43 PM
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Originally Posted by Leafy
Oh yeah, certainly not slow, both drivers beat me, their time gap was bigger on the POWAHHHHHH course than the technical course though. And there's a ton of money in the car, there's an efr under the hood if I remember right from impound. Remember he has an inch that he can hammer out in the sill area to gain more clearance before he's illegal, I think he can get enough steering lock to be fine on most national size courses.
An inch? I guess I need to find that in the rules didn’t realize there was any leeway inbord of the wheel mounting face.

FWIW I beat Duke Langley all three events we faced each other last year including NT right before the championship. He finished 3rd and was in second after the first day. Makes me wonder if he stepped it up a notch somehow at the finals, he was quick!
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Old 02-21-2014, 04:46 PM
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Outboard of the hubface you can do whatever you want to the fenders in order to clear tires. Because its street mod you can modify pretty much any part of the car by 1inch and 1 pound to facilitate an otherwise allowed modification.
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Old 02-21-2014, 06:13 PM
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Originally Posted by Leafy
Outboard of the hubface you can do whatever you want to the fenders in order to clear tires. Because its street mod you can modify pretty much any part of the car by 1inch and 1 pound to facilitate an otherwise allowed modification.
Um that changes the game a bit. 1" bigger intire inner fender?
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Old 02-21-2014, 06:42 PM
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Originally Posted by bbundy
Um that changes the game a bit. 1" bigger intire inner fender?
That rule does come with the caveat to not take advantage of the rule. IE, dont **** it up for the rest of us. I say hammering the living **** out of it is within the spirit of street mod. Cutting out, moving and rewelding sizable piece of the chassis is a no.

I still dont think the 315s are worth 200 pounds and 3 inches of width.
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Old 02-21-2014, 07:23 PM
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Originally Posted by Leafy
That rule does come with the caveat to not take advantage of the rule. IE, dont **** it up for the rest of us. I say hammering the living **** out of it is within the spirit of street mod. Cutting out, moving and rewelding sizable piece of the chassis is a no.

I still dont think the 315s are worth 200 pounds and 3 inches of width.
Yea I still question the tradeoff. If my car had to weigh 200 lbs more though I could run it in open track form all the time and keep the roll bar on maybe a cage. But I couldn’t imagine that size tire being faster on the track not to mention the added cost in tire budget.
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Old 02-21-2014, 09:54 PM
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Those are basically the same dimensions as the tires we have on the front. 1" is not enough clearance for an NA chassis. Can't say I know about any other chassis. I'm guessing the factory wheel well size increased over the years and models as tire and wheel sizes increased.
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Old 02-22-2014, 12:25 PM
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Originally Posted by guttedmiata
Those are basically the same dimensions as the tires we have on the front. 1" is not enough clearance for an NA chassis. Can't say I know about any other chassis. I'm guessing the factory wheel well size increased over the years and models as tire and wheel sizes increased.
I have both NA and NB chassis bare gutted sitting side by side. The only advantage the NB has is in the outer fender lip area, which doesn't matter when looking at tires this big as both would still need to be modified there. The NB is 10mm wider per side in the rear and 5mm wider per side in the front but much of the inner fender shock top area metal pieces appear to be made on the exact same tooling. This change is the same as OEM width change in suspension and wheel offset made by Mazda but there was no change made to accommodate larger diameter that I can see.
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Old 02-22-2014, 07:11 PM
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Originally Posted by bbundy
I have both NA and NB chassis bare gutted sitting side by side. The only advantage the NB has is in the outer fender lip area, which doesn't matter when looking at tires this big as both would still need to be modified there. The NB is 10mm wider per side in the rear and 5mm wider per side in the front but much of the inner fender shock top area metal pieces appear to be made on the exact same tooling. This change is the same as OEM width change in suspension and wheel offset made by Mazda but there was no change made to accommodate larger diameter that I can see.
I'd sure want to investigate the rear portion of the inner well if the car were in my class.
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