C3 - 1971 Will This Size Tire Fit My Vette????

[Peter B.]

Looking to get BFGoodrich TA Radials. I was looking at 255/60/15 but was told that on a '71, it will rub on the outer front well.

I was then recommended by someone in NCRS to go with 245/60/15. Those will not rub.

Any other input you can help me with? I plan to go with the 245/60/15.

[Joe L.]

Re: C3 - 1971 Will This Size Tire Fit My Vette????

Peter-----

I always recommend the 245-60-15. I have used this size for years with no interference problems, whatsoever. I've heard conflicting reports on the 255-60-15. Some folks seem to use them without modification to the fenders and others have had problems without, at least, slight fender modification. I think that the problem is that they are very close to fitting, so slight differences from car-to-car is waht makes the difference. For me, this indicates a fitment that is way too close, even if the tire appears to fit ok upon installation. So, personally, I would never use a 255-60-15, even if I were using the tires on a 1970+ with fenders which are somewhat different than my 69.

[Peter B.]

Re: C3 - 1971 Will This Size Tire Fit My Vette????

Do you recommend 245 in the front and 255 in the rear or go 245 all around?

[Joe L.]

Re: C3 - 1971 Will This Size Tire Fit My Vette????

Peter------

I recommend 245-60-15 at all four corners. I wouldn't even consider using 255-60-15 on the rear only, even if they would fit without problems.

[Peter B.]

Re: C3 - 1971 Will This Size Tire Fit My Vette????

I will be replacing 225 70 15 Firestones. On Tirerack, their overall Diameter is 27.3inches. The overall diameter of 245 60 15 BFG's is 26.6 inches. that is a .7 inch difference in Diameter.

Do you feel it will look good with less wheel well filled in?

[Warren F.]

Re: C3 - 1971 Will This Size Tire Fit My Vette????

For your information, Goodrich Euro T/A 265x50x15 size tires will also fit. I have had four sets of tires on 3 '70's & 1 '71 Corvette, all fit with no modification to wheel wells.

[Joe L.]

Re: C3 - 1971 Will This Size Tire Fit My Vette????

Peter-----

I think that it will look fine. In my opinion, the 225-70-15 look to be too big in the wheel well. I realize that the 225 is close in diameter to the original F-70-15 size. However, the tread width and general configuration of those tires were different. To me, the 225-70-15 look "oversize" in the wheel well regardless of the fact that their diameter is close to the original.

[Joe L.]

Addendum

Peter-----

One other thing. The OD of the original F-70-15 was 26.95". So, the 225-70-15 is actually 0.35" LARGER in OD than the original tire. The 245-60-15 is 0.35" SMALLER in OD than the original tire. The smaller OD helps "compensate" for the extra tread and section widths of the 245-60-15 tire and prevents fender/tire interference.

The 255-60-15 is 27.05" OD. However, it has a section width of 10.24" compared to the 9.76" section width of the 245-60-15, 8.98" section width of the 225-70-15 and 8.95" section width of the original F-70-15.

The 255-60-15 has a tread width (depending on tire make/model) of 7.7" compared to the tread width of 7.4" for the 245-60-15 (depending on tire make/model), 6.7" for the 225-70-15 (depending on tire make/model), and 6.5" for the original F-70-15.

When you combine all of the larger dimensions of the 255-60-15 over the original tire size, you end up with a tire that, overall, is considerably larger than original. Therein the fitment problems are created.

When the 255-60-15 tire size was added as an option beginning in the 1978 model year, there were TWO changes that were made to accomodate these tires. One change involved a St. Louis modification to the 78+ style fender lips.

Corvette trivia question: can anyone tell me what the OTHER change was?

[Patrick H.]

Re: Addendum

Joe,

Didn't they also change the front lower control arm bump stop (I think that's the name of it) to prevent interference?

Patrick

[Joe L.]

Re: Addendum

Patrick-----

You got it!

[Patrick H.]

Re: Addendum

So is my reward a visit to your parts place heaven when I come out to Monterey in March? How about meeting me for dinner - and YOU pick the restaurant!

Patrick

[Joe L.]

Re: Addendum

Patrick-----

Sounds good to me. We couldn't do much better than the place we were at the last time, but for the sake of "variety" I think I could come up with something "new and different". Let me know ahead of time when you'll be in Monterey.

[Dan Tewell]

Re: Addendum

Joe, there must have been more than 2 changes then. The cars with 255-60-15 had the rear inner edge (where the rocker molding atatches) cut back at an angle so the tire wouldn't rub. This change also required a shorter rocker molding. There were actually two different part numbers for 78 fenders and rocker moldings.
What do I win?