and read what the Brits were thinking of the Split

[Rob M.]

I found this nice article today in The Motor of December 1963...




Chevrolet Corvette Sting Ray (The Motor, Dec. '63)

[Duke W.]

Re: and read what the Brits were thinking of the S

This is a better and more comprehensive review than typical American car mags of the time.

The lead photo indicates oversized rear tires and, indeed, the article states that this example was equipped with the optional nylon cord blackwall tires, but the rears were oversized, 7.10-15!!!

Most of the reported tire deficiencies would be solved by radial tires as I found when I installed a set of 6.70-15 Michelin X radials on my SWC in 1964.

I found it interesting that they described the J-65 metallic brakes as "superb", but did note a few deficiencies. Based on my experience I wholeheatedly agree as they hauled my car down from high triple digits speeds on many, many occasions, including hot laps at Kent, and based on the standards of the day, they worked quite well, the deficiencies being something that you learned to compensate for, but the bottom line is that they always WORKED when you really needed them.

Also, of note: They say the steering has a "hydraulic damper". Apparently they just read the specs and didn't look under the car, but for many years I thought that GM had forgotton to install one on my car as the specs didn't indicate that is was not included on SHP/FI engines. It wasn't until many years later that I realized it was not installed because it wouldn't fit on the engines with the big oil pan.

Duke

[Verle R.]

Re: and read what the Brits were thinking of the S

I replaced the original tires on my 65 L79 within about six months with Pirelli Centurato CN72 205HR15. They made a world of difference in driving and all facets of handling; wet and dry handling, braking and acceleration. I continued to buy the Centuratos until Pirelli quit importing them about 1970.

A set did not last many miles but they were fun miles.

Verle

[Duke W.]

Re: and read what the Brits were thinking of the S

I replaced the Michelins in 1968 with the same tires. They were not yet released in 1964, however, I did evaluate the available Pirelli Cintuato 367 at that time, but the largest size was only 185-15. The other tire I evaluated in 1964 was the Goodyear Blue Streak Sports Car Special, which was a treaded racing tire of the time.

Initially, when mounted on the OE 5.5" wheels the CN 72's performance was disappointing, so I bought a set of 68 Corvette 7" wheels, and the improvement was dramatic - more grip than the Michelins with more predicatble breakaway characteristics. The CN 72s were actually referred to by Pirelli as "low profile 70 series" even though they carried a conventional standard profile metric size designation.

You may recall that those tires (and the later CN 73s) were fabric, not steel belted. Pirelli's claim was that their breakaway characteristics were more benign than the steel belted radials of the day, and they were correct, however, the industry finally solved the sudden breakaway characteristics of early steel belted radials, and Pirelli went to steel on most models after the CN 73.

IIRC I got about 40K miles out of the CN 72s (running them virtually to the cord) and replaced them in '76 with 225/70VR-15 CN73s, which was the follow on model, and also excellent and far superior to any domestic brand radial, none of which were speed rated at that time and many were known for tread separation problems.

Duke

[Duke W.]

PS

If GM Europe had equipped their test cars with European radials, I'm sure the European press would have been much more impressed with the ride and handling, though they did realize that many of the ride/handling deficiencies were caused by the bias ply tires.

However, Duntov was dead set against the use of radial tires for reasons I've never understood. I found nothing but improvement back in 1964, and that remains the case today for anyone who switches from bias repros to even cheap low speed rated radials that mimic the look of the OE tires.

High speed rated radials offer even better performance plus the safety of a nylon cap belt that virtually eliminates the possiblity of a catastrophic tread separation.

Duke

[Verle R.]

Re: and read what the Brits were thinking of the S

When I installed the Centuratos I mounted them on 15X7 American Racing Mags with zero offset. The fit well and made the tires work well. As I remember, the Pirelli literature recommended six or seven inch wide wheels for the 205. My brother installed a set on 5 1/2" wheels and they didn't work well at all.

Verle

[Duke W.]

Re: and read what the Brits were thinking of the S

Yes, Pirelli pointed out that wheel width was as critical as tire width, and installed wheel width must be suitable to tire width, which is why I decided to replace the OE wheels with wider wheels, but wanted to run my OE wheelcovers, which attached to the Corvette 7" wheels with no problem. Pirelli's technical literature including their "Pocket Tire Guide", a couple of which I still have, was unmatched in the industry.

Back in that era there was nothing else even remotely comparable to those H and V-rated fabric belted Pirellis, and they would still be competitive with most modern high speed-rated tires of similar size suitable to Corvettes like the current V-rated 225/70R-15 police pursuit tires, and Pirelli's current 215/70ZR-15 P4000 Super Touring is the pick of the litter for C2s with OE or slightly wider wheels of proper offset that fit the fender wells without t******* the lips.

And you and I were way ahead of the pack for understanding these issues 30-40 years ago.

Too bad Duntov never got together with Pirelli back in that era, but I think corporate management would have nixed placing "foreign" tires on Corvettes back then even if Duntov would have wanted to go that way. The American manufacturers were way behind on radial tires until the eigthies when they introduced speed-rated radials, interestingly, on the 1984 Corvette.

Duke