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Old 04-15-2013, 06:59 PM   #1
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NT-01 Front Fitment

I just bougt some NT-01's to try for track days and maybe a few auto-x events.

The rear 275's fit fine, but I am having a problem with the front 245's scrubbing hard on the inside wheel well liner when the steering is turned more than 1/2 turn. This is maybe marginally OK for most race tracks, but I I would like to get 1 full turn of the steering wheel.

These 245 / 40-18 NT-01's are specified at 25.55" OD, which seems to be the limiting factor. They are mounted on 18" x 8.5" wide OZ wheels with a 53mm offset. These same wheel work fine with a 255 Dunlop ZI, but the ZI has a 25" diameter.

I could drop down to a 235 / 40 NT-01, but that only gets the diameter down to 25.35". I would have to go all the way down to a 225 NT-01 before I can get the diameter down to 25.1".

Has anyone else had this problem with NT-01's?

Thanks for any info.
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Old 04-15-2013, 07:21 PM   #2
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The liner has tabs that will allow you to adjust it inward for more clearance.
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Old 04-15-2013, 07:22 PM   #3
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I run the 235 with no issues at all
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Old 04-15-2013, 08:35 PM   #4
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When I run square with 255/40/17s up front, the tire will just rub at full lock. Lots of guys run 247/275 with no issues. See if you can adjust your liners.
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Old 04-16-2013, 02:44 AM   #5
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Thanks for the info. guys. I had my wheel liners off a few months ago to see how difficult it would be to move he radiators forward, but I do not recall any significant adjustment possible, and my liner was right up against the radiator mount.

I have GT-3 lower control arms set near maximum with about -3 degrees camber, so that may be giving me a different result.
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Old 04-16-2013, 03:35 AM   #6
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doug -

are you sure this is the right tire for you? i am of the opinion that you do not need to be any faster......
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Old 04-16-2013, 06:27 AM   #7
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Quote:
Originally Posted by LAP1DOUG View Post
Thanks for the info. guys. I had my wheel liners off a few months ago to see how difficult it would be to move he radiators forward, but I do not recall any significant adjustment possible, and my liner was right up against the radiator mount.

I have GT-3 lower control arms set near maximum with about -3 degrees camber, so that may be giving me a different result.
You may want to re-align a bit to use NT-01s. I run about -2 degrees for very even wear. Nittos don't need as much camber as RA-1s or other Rcomps. A small wheel spacer may also be in order.
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Old 04-16-2013, 12:48 PM   #8
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doug -

are you sure this is the right tire for you? i am of the opinion that you do not need to be any faster......
Thanks, but I can't match your Hp, so I need all the help I can get...
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Old 04-16-2013, 12:58 PM   #9
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Quote:
Originally Posted by Topless View Post
You may want to re-align a bit to use NT-01s. I run about -2 degrees for very even wear. Nittos don't need as much camber as RA-1s or other Rcomps. A small wheel spacer may also be in order.
Thanks for the suggestion. I tried some 7 mm spacers already but that was no help.

Everyone's comments started me thinking on what could be different, and it finally hit me - I have adjustable caster with the lower control arms that I'm using, so I should be able to back off the huge amount of caster I'm running and directly improve the tire scrub.

Thanks all
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Old 04-16-2013, 05:45 PM   #10
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Just a follow-up for future reference - I dialed out a bit of caster, and now the 245 NT-01 fits fine, and I can do over one full turn of the steering wheel without scrubbing (much), so should be good for both track day and auto-x use.
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Old 04-16-2013, 08:11 PM   #11
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Quote:
Originally Posted by Johnny Danger View Post
The liner has tabs that will allow you to adjust it inward for more clearance.
That post should earn +rep ... if we had that.
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