71 WHEELS AND TIRES

You might want to try and message wzschirnt  check out his ride on this post:

http://c3corvetteforum.abouteverythingsite.com/show-off-your-c3/having-fun-with-my-74/

thank you very much for the reply. i have not yet purchased the cragars yet. i went to a vette show sunday and my wife really liked the stock rally wheels she saw on the 71 stingrays, so it looks like i'll run the stock wheels for a while. i am still torn between the 235/70 and the 255/70/15's. the speedo is not an issue, but i'm a little concerned about clearance on the inside. i'll just have to make a trial fit. palmbeach,your 76 looks great and thanks for the input.

thank you for the link. i'll put it on my favorites.

Handling will be affected more by the sidewall height. A 50 series is lower and wider so a shorter, stiffer sidewall will flex less than the 60 series which is taller and not as wide. The tread width will give more traction which increases performance regarding reduced wheel spin, but if smokey burn outs is what your looking for than a 60 will light up faster and easier than a 50. Then you have to factor in the compound of the tire too. A harder compound less traction (bite) and a softer tire has good traction but doesn't last long.

Not stiffer, actually the opposite and just taller with more sidewall flex. The more sidewall a tire has the more energy can be absorbed and a smoother ride is obtained since alot of the imperfections in the road are not felt. Low profile tires (50's and smaller) are stiff in the sidewall to prevent flexing which makes them handle great in cornering situations but they transfer every nook and cranny in the road through the car and the steering wheel. That's why luxury cars and trucks have alot of sidewall, partially for the comfort ride but also load ratings. Sports cars have less sidewall to handle the speeds their capable of and hopefully to keep the car planted to the ground when the go fast pedal meets the floorboard 

To determine the compound you have to check with the manufacturer for specifics but a easy way is to look at the Treadwear number on the sidewall, the lower the number the softer the compound and the higher the number the harder the compound. Treadwear is generally used as a selling feature regarding the mileage longevity of a tire. 320 used to be the average for a car tire but a 220 or 180 was the sport ZR rated tires. Now some companies are increasing the tread depth which also increases the Treadwear rating though the same compound may exist but since the depth is greater the tire would last longer since you start with more material, that's where you would have to check with the company for specific compound questions.

For a daily driver the 60 series is the most popular tire on the Corvette in the original 15" wheel size (255/60r15) the factory tire on most C3's was a 225/70r15 which was around 27 1/2" tall. Using the tire calculator I posted earlier in this thread you can compare different tires sizes to your current size and also change the wheel size and tire accordingly. That's how I chose the 18" wheels for mine since a 255/45zr15 was a 1/2" shorter than the factory size on paper.

Excellent! Even before I lowered the car and put the bigger front sway bar in, she handles great and the tires balanced up nicely, even my wife commented on how smooth the car is on the interstate and then she says  "she feels like she just wants to go" then I grin  and crack open the throttle

I bought Centerline Champ 506 wheels. 18" x 8" all the way around with a 4" rear spacing. Centerline made them since they can do most any back spacing you want, so they don't keep them in stock. It took 4-6 weeks to build but I used to sell Centerlines at Super Shops and they are a great quality wheel.

Your right Cragar SS's in an 18" would be hard to find since it was only recently that they offered the larger wheel size. Many moons ago the biggest you could get was a 15", sold a bunch of those too, only draw back is the chrome after a long time can pit, surface rust and flake off.