This morning I noticed my new wheel/tire combo on my 1969 is rubbing on the front. I need some help figuring out where to go from here.

The new whees are 17x11 with a 4" offset. Tires are Kumho Ecsta XS in 315/35/R17, the specs list them as being 25.7in in diameter, tread width is 11.5". I am rubbing on the edge of the tire on the inside of the fender. My track tires are Hoosier Street TD's in 275/45/16. They don't make the Street TD's in this size anymore so based on a same size R6 they tread width is 10.6". I think the tread with is where I am getting in trouble. They make a 295/35/17 size in the Kumho that should still fit the 11" rims, they do not list a tread width (going to call for that tomorrow) for that size but for general comparison a Hoosier R6 in that size is 10.8", so assuming the Ecstas in that size are withing +/- .1" I should be close as that would be a gain of almost 1", or 1/2" to one side.

I am trying to avoid getting new wheels are tires, but at the same time I am not going to let the extra $500 the whees are going to cost above getting new tires stand in the way of driving the car. Just looking for some ideas. I have a pair of race wheels that are 10" for another car with R6's on them that I am going to give a try as well, just to give an idea if 1" off the wheel/tire would solve the issue.

 

Holy cow, an 11 inch wide wheel on the front without flares? And you want it to fit?

First thing you need to remember, the width of the wheel will change the width of the tire. Four inch offset (what, 1.5 inch backspacing and 9.5 inch deep dish?) Or do you mean 4 inch backspacing?

With a 4 inch backspace, you have 7 inches sticking outside toward the fender. This will add extra load to the bearings and shove everything outside to rub outer fender and the inner fender with turned lock to lock. You need more like 5 inch or 5.5 inch backspacing to make it work, but then you run into clearance issues on the tie rod ends and A-arms. But on 17 inch diameter, you may clear them. You need to trial fit the wheel and see what is close and what isn't and go from there.

Or if you know someone with the right wheels and tires, try them on to see what you can do and can't do.


Also, every one of these cars are different. What fits some might be a bit too tight on others.

Good luck.

 

I have flares all the way around.



Sorry I meant 4" back spacing. When I bought the car it at 17x11 Real Racing wheels with 4" back spacing. Right or wrong the past 2 owners have been running the car like that for 15+ years and while close the clear fine. I could not find street tires for the racing wheels so I bought TT II's in the same size, in hind sight I should have went to 10's in the front. I don't think I could run much more back spacing, maybe an inch tops if that. I checked that before ordering the TTII's as I had a concern this would happen.

I put on a set of 15x10's with 275/50/15's from our 72 to see how they fit/clear and there worked well. So now I am probably going to bite the bullet and just order another set of 17" TTII's in 9 to 10" wide. I would try a 295/35/17 tire first on the current 17x11 but no one has them and I don't want to waste $200. I will just be a head a set of rears for auto-x.

Yeah I am quickly coming to terms with the fact that C3's body's are not perfectly symmetrical, especially one that has had a new front end and fender flares attached to it.

 

Your flares are too low. They look better but they don't give the room to put on a lot of rubber under them.

I ran 16x12 on the front but with only 4 inch backspace. I wanted 4.75 to 5 but due to extra cost and me having a tight budget at the time, I stayed with 4.00 inch. 15 inch is too tight to the tie rod ends to go much past the 3.50 on the stock 15x8 Rally wheels. The 16 was enough to get some of the tie rod inside.

I imagine, but don't know, that 17 inch would let all of the tie rod inside. The only issue would be in a turn that the tie rod itself could rub on the rim. The same on the front of the A-arm in that the rim could hit brackets up there. You need to turn to lock front and rear and check on each side. You'll have to look for what the rim would hit if it were about an inch or 1-1/2 deeper (further inside).

Believe it or not, a 1/2 inch is a lot and an inch is a whole lot of change. So if you can squeeze another inch, it is a bunch.

There is a rather complicated set of calculations to tell you what you want, but the simple means of the ideal placement is that the center of the tire patch should be the point where a line through the ball joints hits the pavement. This could mean your wheel needs more or less backspacing and more or less rim width.

The 17s on your car look good, so I wouldn't go back to 15s, especially since it is hard to get decent tires in 15 inch.

 

Thanks for the help. I will get the car up and see how doable more back spacing would be. I am hitting the front the fender about 40-50% way to full lock, so any amount of reduction to the outside be it more back space or a smaller wheel would solve the issue.