20mercury

Know this tire thing has been beat to death, but I really need some advice here.

So, I would really like your opinions on the best tire to buy for a 68 convertible with AG 15x7 rims as I am going around in circles as to which way to go!

BTW, Discount Tire direct is having a sale/rebate this weekend too, you might want to check out. Thus I must get off the pot and decide, ha!

For me, I am thinking 225 70 15 which would maybe be better on a 15x7 rim since the tire width is 8.86" wide and is pretty close to the original GR70 15 and a 7 inch rim is of course 7 inch and more narrow.

Or, I think the 255 60 15 might look better as a fatter tire, but may have tire rub, I could live with a slight kiss at full lock, but maybe be a stretch to put on a 15x7 rim. I am wondering if the 255 60 15 might be too fat at 10.04" wide to safely put on a 15x7 rim.

So, question: is it ok to put a 255 60 15 on a 15x7 rim? Or the 225 70 15 would be a very acceptable choice and better on a 15x7 rim??

Much thanks!

MelWff

according to ww.tirerack.com the 255 60 15 is for rim widths of 7 to 9 inches

20mercury

Thanks and this is very good to know!! At least, it is "ok" to install a 255 60 15 on a 15x7 rim. Thanks again and this eliminates one of my big concerns.

gbvette62

To start with, the GR70R15 was not the original type or size tire, that was installed on 68 Corvettes. 68 Corvettes came with bias ply F70x15 tires. GM did not put radials on the Corvette until 1973, and 73 was also the year they went up a size from the F70, to the GR70.

The modern radial equivalent to the F70x15, is a P215/70R15, not the 225. The 215 is basically the same diameter as the F70, so when installed on a 68, it will be closer to original in both height and appearance.

You can use P255/60R15's on a 7" rim, but that's at the low end of the recommended rim, for that size.

255/60's were optional on 78-82's, and will fit with almost no issues. There's no clearance issues at the rear, but some people have experienced problems with them rubbing on the from. When installed on the front, 255/60's have been known to rub on forward edge of the wheel opening lip. When 255/60's were ordered on 78 & 79's, the factory trimmed the front edge of wheel opening, to prevent them from rubbing (this wasn't an issue with 80-82's, because of the wider combination front bumper/spoiler on those years).

You may want to consider a P245/60R15. The 245/60 is the 60 series equivalent to the 215/70, and 7" is the recommended rim width for the 245/60. You should have no clearance issues with a 245/60 either. The drawback to the P245/60R15, is it's limited availability. I think BFG is the only company still making a P245/60R15 tire?

20mercury

Good info and thanks as this helpful!

PRNDL

225 70 15 work well for me. I had a wider tire before that and the change made a big difference in how the car handled. Much less "wandering" and following ruts on the highway with the narrower 225/70 tires. If your suspension is tight and perfect it might not make any difference to you, but if your 68 is just a tad loose and sloppy like 95% of them that are still drive-able, then you might notice a difference.




better side view....

loup68

I love my BFG 245 60 15's on my 68 coupe. Had them for years. Lou.

20mercury

[QUOTE=PRNDL;1588955175]225 70 15 work well for me. I had a wider tire before that and the change made a big difference in how the car handled. Much less "wandering" and following ruts on the highway with the narrower 225/70 tires. If your suspension is tight and perfect it might not make any difference to you, but if your 68 is just a tad loose and sloppy like 95% of them that are still drive-able, then you might notice a difference.




better side view....

[/QUOTE

Beautiful Corvette!!! Is that LeMans blue? Or International blue?

Mine is a LeMans blue, but a base 327, Your 427 looks great!


Thanks for all of the responses and advice!

7T1vette

235R60-15 tires are about the same diameter as the F70-15's that came from the factory. And, I think that size tire looks really good on C3's. Tires wider than that just cost more, force you to change speedo gears to get a correct speed, and lower your mileage due to more road friction.

If you wanted to road-race it, you'd go with larger rim sizes and more modern tires, anyway. Just my .02...

capevettes

I'm running 225-70-15's on my 68 with stock rims. They seem to hit the sweet spot for handling, appearance and no rubbing. I bought redlines from Diamondback Radials. Nice tires

hummiscorvettetaken

Took your advice for my 68 and went the same way, new 245 60 15's on 7" wheels being installed during the restoration - I think the size looks right!

loup68

You will REALLY like how fast you can take a corner now! Glad that I could help you out. One time I needed new tires and they only had 235 60 15 and they are way too short and do not fill up the wheel well.
Lou.

7T1vette

Sorry, 235R60-15's are the same O.D. as the stock F70-15's. But, everyone should get what they think is best for their ride.