(Message Deleted by Poster)

[Paul DeFrance]

Message Deleted by Poster

[Richard D.]

Re: 77 tire size recommendation

Paul:

From my understanding, 255's are the biggest that will work with C-3's, although 68's may have some problems, in which case, 245's are the way to go.

Read that in Newton's restorer's book.

Rich

[Paul DeFrance]

Re: 77 tire size recommendation

Thanks for the info Rich,

Did Newton's restorer's book mention
wether it is a 60 or 70 series tire?
There is a little over 1/2" dif in width
between the two.

Thanks again,
Paul

[Richard D.]

Re: 77 tire size recommendation

Sorry Paul, he was talking about 60 series tires.

I posted a message down below on the 8th "68 Tire Size Recommendations" that some folks posted some good info to.

One of the members said he's running 255/60 on his 68 BB with no prob.

Rich

[Craig S.]

Re: 77 tire size recommendation

Paul - make sure you really want large rubber on the front of your car. I once installed a set of Goodyear Eagy GT tires (255-60-R15) and while the only trouble I had with clearance was on hard left with a slight rub on the fender lip (I didn't want to do the factory shave of the lip like they did on the late 70's sharks to use this tire size) I really liked the nimble feeling of the smaller tires better for steering. Remember, you are adding more rotating mass out there, and you will feel it in the handling. It is a personal choice, but I would not go that large again. At the time, I was using American Racing Cyclone wheels that were 15X8.5, one half inch wider than stock, which may have affected the clearance over the 8". I don't remember the offset compared to the original rally wheels however....Craig

[Richard D.]

Re: 77 tire size recommendation

Craig's response is really good.

I think at a certain point, aside from "looks", it all becomes a moot point.

Probably, tire size beyond 235/245 exceeds capabilities of the suspension anywyay, and aside from racing your car, who will ever really need it?

And if you don't have power steering, it makes if really hard to turn the old wheel.

Same for tire speed ratings, if you're not racing, after 110 or so, what's the dif.?

Rich

[Patrick H.]

Re: 77 tire size recommendation

I run the 215/70R15's on my 71 which are as close as you'll get to a "direct replacement size" for that year. I think the capability of the tires is far better than what was used in 1971, and since I don't autocross the car nor drag race, it won't make any difference what size I use. I always think the 225/70's that are the "direct replacement size" for 73 and later look too big on pre-73 cars.

Just my thoughts.

[Duke W.]

Re: 77 tire size recommendation

I finally have to jump into this one - seems that most guys think a wider tire means better handling. Absolutely not true!!! If your primary concerns is appearance, then a 255/60 is probably your choice, but keep in mind that all tires in this size have no better than a "S" speed rating, and typically have very hard compounds with UTQG ratings or 400 of more. Such tires are not performance tires by any stretch of the imagination!

If you are looking to maximize the sports car handling characteristics of your vintage Corvette, selected seventy series tires are the way to go. For C2s the biggest you can install is a 215/70R-15. It's best to install them on six inch wide wheels and the pick of the litter in this size is the W-rated Pirelli P4000 Super Touring. This size is the same revs per mile as the OEM 7.75-15 and F70-15, so it's suitable for early Sharks, too, but I would recommend at least a 225/70R-15 for all Sharks including '68s with seven inch wheels.

Fortunately for us there are three "police pursuit tires" that were designed for the old Caprice 9C1 police car, and they are still available - Goodyear Eagle RSA, General XP2000V, and Firestone PV41. These are also available in a 235/70R-15, which I would recommend be considered for Sharks with eight inch wheels.

The performance characteristics of a tire have more to do with its internal construction features and rubber compounds than aspect ratio or tread width. It's impossible to "see" these characteristics, but the speed rating and UTQG tread wear rating are surrogates, so if you want the best performance tire, go with a suitable size that has the highest speed rating and the LOWEST tread wear rating.

Duke

[Patrick H.]

Re: 77 tire size recommendation

If a 225/70 looks tall on a 68 and later, I'd have to think a 235/70 would look even more so. Sort of like stuffing station wagon tires under a Corvette.

Then again, I usually seem to be in the minority in thinking they look too tall. Oh well.

PH

[Duke W.]

Re: 77 tire size recommendation

Yeah, they might look a little "tall", but because of their greater load capacity, they will have crisper steering response and better lateral g limits than the same model 225/70. That's why I say they should be considered by Shark owners with 8" wheels. Too many brains have been warped by these stupid low profile tires on modern cars, but they sure are profitable for the tire companies

Take a look at the tires on F1 cars, They're about 24" tall with 13" wheel diameters. CART and IRL use 15" wheels with about 25" OD. So much for low profile tires being the "ultimate" in performance!

Clem probably remembers "oversize" tires from the fifites. Back then you replaced the OEM 6.70s with 7.10 or 7.60 truck tires. Those were the "racing tires" of the era.

Duke

[Craig S.]

Re: 77 tire size recommendation

Paul - any of them will work fine is the reality of the situation. But, when I installed the 255/60/R15 Eagle GT's (Had the "wonderful"Firestone Steel Radial 500's in GR70-15 as I recall before) I immediately noted that I felt the "flywheel" effect in the steering when winging the car around, I actually liked driving it less than before, and had more of a tendency to catch road groooves than before. Of course, at that time in my life I thought it looked bitchin in appearance. I just didn't care for the less precise steering feeling it afforded the car. Again, just some thoughts and my 2 cents, what you should do is what makes you happy.