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[froop]

Hi,

My current set up is Forgestar F14s with Federal 595RSR's

Front: 18 x 8.5 ET48, 255/35/18
Rear: 18 x 9 ET50, 225/40/18

Once these are bald I want more rubber on the front and rear but I'm not sure what to squeeze onto the fronts. I know with a 9" 265 is the widest I would go on the rear so my choices are either R888s in 235/40 on the front with the same circumference as the rears or go 595RSRs in 245/35 with wider rubber but smaller circumference.

Is there any real issue with running different circumferences on front and rear sets?

Thanks for your help in advance.

[Nugget]

Originally Posted by froop

Hi,

My current set up is Forgestar F14s with Federal 595RSR's

Front: 18 x 8.5 ET48, 255/35/18
Rear: 18 x 9 ET50, 225/40/18

Once these are bald I want more rubber on the front and rear but I'm not sure what to squeeze onto the fronts. I know with a 9" 265 is the widest I would go on the rear so my choices are either R888s in 235/40 on the front with the same circumference as the rears or go 595RSRs in 245/35 with wider rubber but smaller circumference.

Is there any real issue with running different circumferences on front and rear sets?

Thanks for your help in advance.

Should be fine, I'd do 245/35/18. It's cicumfrence is only 1.35% less than 225/40.

[froop]

Originally Posted by Nugget

Should be fine, I'd do 245/35/18. It's cicumfrence is only 1.35% less than 225/40.

Ah great thanks! It'll be nice to have wider rubber on the front anyway to reduce understeer as much as possible.

[Nugget]

Originally Posted by froop

Ah great thanks! It'll be nice to have wider rubber on the front anyway to reduce understeer as much as possible.

I would check how much room you have with your current tyres first though.
This is a really good sight for it.
http://www.willtheyfit.com/

Even if it fits in the guards there might not be enough room between the tyre and the strut.
eg. this is mine with a 5mm spacer

[froop]

Originally Posted by Nugget

I would check how much room you have with your current tyres first though.
This is a really good sight for it.
http://www.willtheyfit.com/

Even if it fits in the guards there might not be enough room between the tyre and the strut.
eg. this is mine with a 5mm spacer

Thanks for the tip! When I had my current tyres installed I wanted to go F 235 and R 265 however the shop advised me to go with 225 due to the lack of clearance on the front and therefore I went with 255 at the rear too to maintain equal circumferences. I might have been able to squeeze 235s on but it would have had maybe 1-2mm clearance and might have rubbed at full lock.

There seems to be more than enough room at the rear to run 265s but I'd most likely need small 3mm spacers to safely run 235s and thicker ones to run 245s. I reckon I'll probably need anywhere between 5-10mm. I'm sure I'll eventually get some adjustable camber at the front and I don't mind rolling the fenders if that means I can squeeze in wider rubber but I'd prefer the minimum sized spacer that I can get by with to clear the strut.

What are your front wheel specs?

[Nugget]

Front wheels are 18x8 et45 with 225/40/18 Advan AD08s.
Was fine on BMW suspension, but the collar of my coilovers is in exactly the wrong place. I'm changing springs to try and fix it so I can put some wider rubber up front.
With the 5mm spacers it's slightly too wide without a roll. Was travelling somewhat fast through the hills and the tyres did a good job of rolling the front fenders when I hit a dip haha.

[froop]

Originally Posted by Nugget

Front wheels are 18x8 et45 with 225/40/18 Advan AD08s.
Was fine on BMW suspension, but the collar of my coilovers is in exactly the wrong place. I'm changing springs to try and fix it so I can put some wider rubber up front.
With the 5mm spacers it's slightly too wide without a roll. Was travelling somewhat fast through the hills and the tyres did a good job of rolling the front fenders when I hit a dip haha.

LOL. I read on some thread here that one guy actually rolled his front fenders with his hands by just pulling on it haha. There was also another thread where a guy put phone books between his front tyres and the fender and got all his mates to stand on the doors and jump up and down haha. Whatever works