Dr Wankel

I'm trying to figure out if these are the correct offsets for these wheels for my FD. The wheels are Blitz Type 03's sized. 18x9 in front and 18x10 out back. Fronts would have a +41H offset and the rears would have a +45H offset. Do these numbers sound good to you guys? I dont think i would have rub problems the car is not lowered and the tires are going to be Nitto NT555 Extreme Perf. sized 245/40/18 and 285/35/18.

Lunar7

Rear numbers look fine.

I personally am not sure about the front. I have 8.5" with +42 offset in the front. If I was going to a 9" in front I would probably be looking at the +45 offset and measuring my car for inside clerance. Coilovers would help in this case but I'm not sure if they are needed.

Hopefully some one with 9's in front will post what offsets they are running.

I would also be thinking about the 255-35-18 tire size in front since it will save you .59" in diameter and might have less chance of rubbing.

Dr Wankel

I will have to do some measuring for the fronts.

I was originally going to go with 255/35/18 for the front but they will end up with a taller sidewall than the rears. My friend has these same wheel sizes on his Supra but he has 255 on the front and i want the sidewalls to be the same. Here are what the numbers will be.

Total sidewall height for the:

285/35/18 = 285 X .35 = 99.75mm

245/40/18 = 245 X .40 = 98mm

or

255/35/18 = 255 X .35 = 89.25mm

So by going with the 245 my sidewalls will be very close in height.

dclin

iTrader: (4)

Don't worry about the difference in sidewall height, front to rear. You honestly should be more worried about fit - specifically the overall diameter of the wheel/tire combo.

245/40/18 is larger in dia then stock, and I guarantee you will have lip contact (even stock spring height) in certain conditions - specifically during full compression of the suspension while turning, like entering an inclined driveway too hot. I found that this has less to do with width/offset of wheel or width of tire. It has everything to do with overall height of the combo.

245/40/18 = 25.72" dia whereas stock is 225/50/16 = 24.86"

Here is my experience: I went from a 235/40/18 (25.4" dia) on a 18X8.5 +40 to a 255/35/18 (25" dia) on a 18X9 +42 and the problem I had with the above situation went away. Not only was the wheel wider and set further out, I also had wider tires. The difference was the dia - where the 255/35/18 is shorter.

Keep in mind that with both were fine for any other situation, hard cornering, suspension compression while going straight, etc - the problem arises when you enter an driveway going to hot. The problem of ripping out my fender lip went away with the 255/35/18s.

I think it has to do with the wheel center being slightly off axis with the top-dead-center of the fender arch. My eyes may be playing tricks on me though. I do know I never had such a problem on my Civic, and I know my Civic tire/wheel combo sat much closer to the fender lip then either one of my RX7 setups. There was literally only a few mm distance from the tire edge and the fender lip. Strange.

Bottom line - from 5 feet way, you will NOT notice the slight diameter difference. Go for fit.

BTW, I have not lowered my current combo yet, so I can't say how it will work with lowering. I am sure mild lowering (say 1/2" via Konis or 3/4" via RB springs) should be OK. I would recommend a narrower width and a shorter diameter tire if you lower it signicantly.

Best of luck!