I know there have been a couple (very few) discussions on this subject primarily using these tires on Type-R's but my search a couple of weeks ago did not result in any definitive answers about rubbing with my particular wheels and suspension setup, so I decided to buy the Hoosier 225-45-15's and see for myself.

My GSR is only lowered 1" on GC coilover kit with 400F/450R 2.5" ERS and OTS Koni Yellows. The wheels are Kosei K1 15x7" 38mm offset. Rear fenders are rolled in.

I was suprised to see that there was no rubbing taking place anywhere when I went auto-xing last weekend. I did not hear anything unusual and there are no scuff marks on the tires upon visual inspection at the end of the event when the tires were off the car.
The ~50sec course was fast in general with some high speed sweepers (50mph+) but there were also some pretty tight sections. After seeing some pics of my car taken by a professional photographer at the site with some very expensive equipment, it was revealed that I was 3-wheeling big time (like 2"+ off the ground) and both outside tires seemed to be slightly tucked into the wheel well.

The A6 performed very well. Definitely a little stickier than the Kumho 710's I used for the last 2 seasons. I 'm sure the larger sectional width of the 225 helped too. Worth the $$ IMO.

Now I have to admit the rear tires were a little too close for comfort to the trailing arms. About 3/16", 1/4" at the most but apparently it wasn't a problem. I have a feeling if I lower the car more it may have some issues but if you have stiffer springs in the rear than my 450's, like 650+ it might be ok to drop the car say 1.5" or maybe more. Not sure though..

The key to using the Hoosier 225/45/15 seems to be the offset of the wheels, and possibly drop depending on the spring rates. Rear fenders must be rolled in and have some negative wheel camber (I have -1.3 deg. in the rear & - 2.3 front). I would suspect trailing arm bushings should be in good shape to avoid excessive latteral movement.

I would like to hear from others using the Hoosier 225-45-15 and particularly how much their car is lowered and what suspension setup they have. I would ultimately like to have a drop of 1.5-1.75" like I used to when I had Advanced Design (double-adjustable monotube) shocks with 600F/750R springs. All I have to do is ship the AD's to GC to get them rebuilt.

 

told ya they wouldn't
-spenc

 

i ran some 225 50 15 v710's on 15x8 949 (38 offset?) racing 6ul's
car is pretty low, but i run 650 fr and 600 rr spring rates. ended up rolling rear fenders quite a bit and cutting the liner out of the front and rolling it. dont forget the seam on the inside of the front fenders as it added a third grove to one of the v710's

 

I'm kind of curious how close the tires come to the (rolled) fenders, and also how close they come to the trailing arms under deflection. Maybe you can tape a piece of 1/8" thick cardboard to the trailing arm, and see if there's rubbing under load.

In any case, I don't think lowering will affect how close the tires come to the trailing arms.

 

Hey Spenc! Yes you did. while I was staging, but I was still very nervous until I got back from the 1st run, which proved you were right

Did you ever break into the 45's? The rain in the afternoon messed me up and I couldn't go any faster. Came close but no cigar. I didnt' stand a chance anyway against Sho's CSP Miata and Chris' Street Mod Civic HB w/Integra motor. Not with my current suspension anyway. Their classifications are screwed up but hey it's the M-Club.. 'nough said. I had fun though. I don't go there to win anymore. I never know what car they 'll throw in my class anymore. 4yrs as a class champion is enough. Let others enjory some of the glory

 

You 're absolutely right jeffhaut. We cannot forget that metal seam inside the front wheel well. I 've had my shares of "new tread lines" on my R tires when I had the 45mm Kosei K1 and lowered about 2" with only 475lb springs up front a few years ago. I can also still see the scuff marks on the inside and top wheel well fender from the tire rubbing. The 38mm offset wheels helped a lot in that respect I believe.

 

remember the 45s are that much shorter than the 50s that they wont rub top.
i didnt get down to where i wanted to at that event but i did stay consistant in the rain. so i guess i was slow in the dry.