Compilation of Road & Track's 54 years of Corvette road test data

[Mark E.]

See attached. I scanned this from the current issue of R&T.

It's an interesting summary of their Corvette road tests since day one, and shows prices, engine data, weight, acceleration, top speed, braking, and skid pad performance.

Best performance in each category is highlighted in red.

Best braking? 2017 Grand Sport
Worst 0-60? 1954
Best 0-60? C6 ZR1 and C7 Z06 (tie)
Lowest top speed for a V8? 1979 L-82 (no results posted for any L-48 or the 1980 California LG4 305)

[Michael J.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

That's really cool, thanks Mark!

[Keith B.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

That's neat but what is the Super Corvette Race Car that was tested in March of 76?

[Jim S.]

Re: Compilation of Road & Track's 54 years of Corvette road test data


This one I Think.

[Loren S.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

That 57 test vehicle must have been one of the factory's finest, 0-60 time looks out of place for the era.

[Bill M.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

That 57 test vehicle must have been one of the factory's finest, 0-60 time looks out of place for the era.

The 1/4 mile times for the '57 (14.3), '59 (14.5), and '61 (14.2) look consistent. They were all solid lifter fuelies with 4.11 gears.

They mention in the test that they ran the '57 to 60 mph in 1st gear, which was 6600 rpm.

They ran the '59 to 58 mph in 1st (6500 rpm) and mention that it was slow off the line. That 0 - 60 includes a bog and a shift to 2nd.

I don't have the test data for the '61 test and they don't mention shift point or bogging....

[Loren S.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

Good info, Bill, that makes sense to me now. These cars were smokin fast for the day.

[Duke W.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

The reason the '57 283/283 was so fast is that it was the lightest production Corvette. They list GHP at 290, but the advertised value was 283. Maybe you FI experts can tell us how they came up with 7 more HP for '58.

I found at least one error in the data. The '67 327/300 0-60 time could not be that fast. Compare it to the '69 350/300.

The increase in roadholding over the years is dramatic. Back in the early days I doubt if any Corvette could acheive 0.75g on the OE tires. Improvement in suspension design, but primarily tire grip is why modern Corvettes can generate more lateral acceleration on the OE tires than racing tire equipped Corvettes in the fifties and sixties. The big improvement in OE tires started with the C4. They were the first speed-rated tires ever installed on a production Corvette, and Goodyear engineers worked closely with Chevrolet ride and handling engineers to develop the suspension/tires as a "system", but... uh, let's forget that '84 Z51.

I recall the test of Greenwood's "batmobile". The 0-60 and quarter-mile times seem slow for such a light car with 700 HP, but it had a CR four-speed and a 2.73 axle. First gear was good for close to 100 MPH, so it was geared far from ideal for drag racing.

Duke

[Michael J.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

Duke, how would you compare the mid-'60s Goodyear Blue Streaks and Michelin racing type tires to the early C4 ones, performance wise.

[Duke W.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

Up to the early sixties, purpose-built racing tires were actually similar to truck tires, but with a lower void ratio (ratio of grooves area to total tread area), and somewhat softer compounds, but still hard enough to achieve about the same tread life in road use as typical road bias ply tires. Cord angles were about 25 degrees (the angle between the crossed plies measured from the circumferential centerline) while pass. car tires were about 35 degrees. The lower cord angle made the sidewalls (and ride) much stiffer. At best, when fresh these tires, like my 63-64 7.00-15 Bluestreaks might generate 0.9g under ideal conditions. The first C4 achieved this level, but without the high slip angles of bias ply tires.

The early Michelin tires were designed for road use, but back in the fifties before dedicated racing tires became widely available they were used by racers, especially in the wet because of their vastly superior wet adhesion compared to bias plys. The 6.70-15 Michelin X radials I installed on my SWC in '64 definitely had more dry and wet grip than the OE General Jetaires, but perhaps the biggest improvement was the vast reduction in operating slip angle, which made the steering much more precise and linear. But on the downside they had a habit of sudden breakaway in both dry and especially wet conditions, so you really had to know the limits. I spun twice on them at 17 and 19, the only two times I ever lost complete control of a car in my life. The first time the road was wet and the second time the road was dry, but I was wet. Fortunately there was no damage to the car, just my ego.

Racing tire technology really began to take off about 1965 and advanced rapidly. Racing tires got wider, with lower profiles, softer compounds, and even lower void ratios until they finally became slicks for dry conditions by about 1970. They were still low angle bias ply, and Corvettes were probably achieving 1g on tracks at that point. Nowadays I think some race cars can pull close to 1.4g on racing tires without the aid of downforce

Duke

[Michael J.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

Thanks Duke, very informative!

[Mark E.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

As an owner of a '70 454, I was embarrassed to see 7.0 sec for 0-60 mph and 15.0 @ 93 mph for the 1/4 mile.

The road test does say the test car was fully optioned (including AC) with automatic, 3.08 axle and two guys in the car with '70s technology test equipment. Maybe this explains why it has- by far- the heaviest curb weight on the list: 3740 pounds- close to Impala territory!

Soon after I purchased my stock LS5 in 1990, I took it to the local drag strip and ran mid-14s at just under 100 mph. That's with an M20, 3.36 gears, amateur me babying the clutch and synchros, and short shifting a little over 5,000 RPM. IIRC, I had to shift to fourth a second or two before the trap, so it definitely wasn't set up for drag racing.

But while my car is also fully loaded, it only carried me and about a 1/4 tank of fuel.

[Michael J.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

Also interesting they didn't have a test on my '81s L81 (190 HP), I suspect that would have made the LS5 in 1970 look like a speed demon. I also noticed the C6 ZR1 has a higher top speed (205 mph) than the C7 Z06 (186 mph). That is surprising since the C7 is supposed to have better aerodynamics, but I guess maybe they haven't been able to push it due to the overheating issues sending the car into "limp" mode. I would expect, when and if they get that fixed, it should go at least as high, but I note the C7 Z06 has also not replaced the C6 ZR1 atop the Nurburgring times yet.

[Mark E.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

Also interesting they didn't have a test on my '81s L81 (190 HP), I suspect that would have made the LS5 in 1970 look like a speed demon. I also noticed the C6 ZR1 has a higher top speed (205 mph) than the C7 Z06 (186 mph). That is surprising since the C7 is supposed to have better aerodynamics, but I guess maybe they haven't been able to push it due to the overheating issues sending the car into "limp" mode. I would expect, when and if they get that fixed, it should go at least as high, but I note the C7 Z06 has also not replaced the C6 ZR1 atop the Nurburgring times yet.

I can't comment intelligently on the ZR1/Z06 comparison, but I can imagine the patience required to drive an '81 L81 at your elevation of 7,000 feet. The consolation: That vintage Corvette is beautifully styled. And how cool to drive one in the condition of yours; they're just not seen anymore.

The current issue of C&D includes a road test of a new Miata powered by a two liter, normally aspirated four-banger: 0 - 60 mph in 6.2 seconds; 1/4 mile in 14.8 seconds @ 93 mph. I think my 454 can keep ahead of it, but barely. And I should probably fear the new turbo four-banger Mustangs and Camaros.

[Michael J.]

Re: Compilation of Road & Track's 54 years of Corvette road test data

Well, I really don't drive the '81 very much, but yes it is not the peppiest car in my garage. Maybe after Bowtie judging, I will drive it more, it is a really beautiful car (won Ladies Choice at Chapter judging recently) and reminds me of my first Corvette, which was an '81 that I had for years, drug it from Houston to Denver to Boston to California and back to Houston, and was forced to sell to buy a Suburban when we had kids, always wanted another. BTW, my son just bought a new Miata like that, he took me for a ride, and it is real fun and moves pretty good for a 4 banger.