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[TrojanBMW]

I've been tracking my car for awhile, and I've decided it's time to get some track-day tires, so I can stop burning up my street-tires.

I'd like to get a square set of Nitto NT05 at 245/40/18 on 18 x 8.5 wheels. I know there's a 235 tire, but I'm afraid that will be too narrow in back.

So my question is, will they fit? I'll be running Vorshlag camber plates up front, and am willing to do some fender rolling to make it work.

I'm thinking +40 offset would work front and rear, but would be willing to run some spacers if necessary. I'm really hoping to be able to rotate the tires front to back so I can get a little extra life out of them.

[larryn]

Trojan, you did your homework pretty well. I ran a similar square setup, and your numbers (including offset) are about as close as you can get to centering the offset differences between the front and rear of the car, with that size tire.

The ET40 8.5" wide wheel should just clear the fender, and the same setup should just clear the strut up front. You'll need around -2.5 deg to clear the fender up front, if you do not intend on rolling the fenders.. and less camber if you're rolled already.

Good luck!

[Eddy@ApexRaceParts]

245/40/18 is a TALL tire. You should be either running 245/35/18 or 255/35/18 if you want to go wider. et40 in the rear is starting to push it.

[TrojanBMW]

Originally Posted by paintpro21

245/40/18 is a TALL tire. You should be either running 245/35/18 or 255/35/18 if you want to go wider. et40 in the rear is starting to push it.

I wanted a 35 profile, but it's not available in the NT-05. The other tire I was leaning towards was the RE-11, and it's the same story.

[mohammadz]

go 255 then....running a tall tire is not good. =)
255 on a 8.5 isnt all that bad.

[TrojanBMW]

Originally Posted by mohammadz

go 255 then....running a tall tire is not good. =)
255 on a 8.5 isnt all that bad.

Would the 255 fit up front?

I wanted to go square and it seems like 245 would be the widest you can go up front, and from what I've found 245/35/18 just doesn't exist in a street/track tire. Tire rack has some pure slicks at the size, but I don't have the budget or time for a tire with a 40 treadlife.

[larryn]

255 NT01s on your ET40 will not work in back without significant fender mods.

I'm running 255's in front, so they fit on a 18x8.5 ET38 with no spacer. I need -3 deg of camber tho. Dunno if NT01s in 255 would fit in front tho, seeing they are super wide.

Of your choices of NT01s, I think the 245/40/18 would be the only one you even have a chance of fitting, unless you went smaller than 245's.

Have you thought of R888's or RA1's? Both are a little narrower than the NT01s...

[TrojanBMW]

Originally Posted by larryn

255 NT01s on your ET40 will not work in back without significant fender mods.

I'm running 255's in front, so they fit on a 18x8.5 ET38 with no spacer. I need -3 deg of camber tho. Dunno if NT01s in 255 would fit in front tho, seeing they are super wide.

Of your choices of NT01s, I think the 245/40/18 would be the only one you even have a chance of fitting, unless you went smaller than 245's.

Have you thought of R888's or RA1's? Both are a little narrower than the NT01s...

To be fair I'm looking at the NT05s not the NT01s. The tires will just be for HPDE schools, and I want something that I can get more than a weekends out of.

That said, I have started looking into either Star Specs, RE-11s or maybe some R1Rs.

Camber plates will definitely be a part of the equation as well. And I'm even thinking 17" might be a better route, but that would eliminate the NT-05s.

[TQ_trackman]

Originally Posted by TrojanBMW

Camber plates will definitely be a part of the equation as well. And I'm even thinking 17" might be a better route, but that would eliminate the NT-05s.

If you go with 17" rims you will have issues with 255/40/17 NT-01's on the rear. I ran them on my car for a few events and got some rubbing, even with a serious fender roll and 2.0 camber. They do just barely fit up front, but that's with a big fender roll, 3.0 camber, and the M3 front pieces. If a square setup is a must then you are probably stuck with 245's.

You might be ok with the 18" 245's as long as your car is not dropped too much, because although they are 1/2" taller than the 255/40/17 they are also 1/2" narrower.

Lastly, the NT-05's were designed to be a drag radial so I'm not sure how good they would be for HPDE, and they are not much cheaper than a similarly-sized NT-01.

[Eddy@ApexRaceParts]

Kumho XS comes in 245/40/18. That is the tire I would recommend if you want to go that route.

There's nothing special about the NT-05.

[mohammadz]

wwops! forgot you are going square...255's up front are not impossible. im running a 245 on a ET34 rim, i dont rub at all...i have 2.5 desgrees of camber though.
what wheels are you mounting on?

listen to paintpro and either drop the idea of a square set up, or drop the nt's even though they look soooooooooooooo good.

[TrojanBMW]

Originally Posted by mohammadz

wwops! forgot you are going square...255's up front are not impossible. im running a 245 on a ET34 rim, i dont rub at all...i have 2.5 desgrees of camber though.
what wheels are you mounting on?

listen to paintpro and either drop the idea of a square set up, or drop the nt's even though they look soooooooooooooo good.

I think I've decided to go square at 245/40 on a 17x8.5 wheels. Vorshlag camber plates and the 17" size should help with the clearances, and there are number of tires at the sizes. I'm leaning towards the RE11s or Star Specs at this point.

Yeah, I've given up on the NT-05s or (NT-01s down the road for that matter). They just don't have that many sizes.