0-60 in 6.1 seconds? That’s nothing nowadays, when dime-a-dozen electric family haulers will do it in under 4 seconds. And plenty of IC cars too. So yes, things have changed since 1969, when this 435 hp 427 Corvette was “more of a race car than a road car”. But in its day, this was a veritable rocket.
R&T points out that the second year of the C3 got some badly needed improvements, after a rather shaky start, literally. A stiffer frame, for starters, improved ventilation, a larger (350 CID) standard engine, and a few other minor details. The 435 hp version of the 427 CID V8 was the highest rated of the three, above the 390 and 400 hp ones, which had a milder hydraulic cam, among other things. The 400 and 435 hp engines both shared the same triple two-barrel induction system, a format that I was surprised to show up on the 427 as it seemed to have had its day in the sun back in the late 50s and early-mid 60s, before the really big Holley four barrel made it redundant. But here it was again.
The one in R&T’s tester also had the optional aluminum heads, which meant that the big 427 weighed only 60 lbs more than the small block, a meaningful reduction over the front wheels.
The aggressive mechanical lifter cam did not appreciably reduce the flexibility of the 427, pulling strongly from 1000 rpm to its bellowing 6500 rpm redline. According to R&T,”there’s simply no production car available today that can top its acceleration”. Hmm. Well, I seem to remember Hemi B-Bodies doing the quarter in about 13.8 or so, about half a second quicker than the ‘Vette’s 14.3 seconds. But the R&T’s acceleration times almost invariably were slower than some of the other mags, so maybe. Or maybe not. And its trap speed of 98 mph does not sound like peak 1969 muscle car era either.
FWIW, average fuel mileage was…10 mpg. Which means the 20 gallon tank afforded less than 200 miles of range. Range anxiety?
The clutch wasn’t too heavy, and the four speed’s shift linkage was “delightfully light and positive”. The power steering was the best yet from Detroit, but “not up to the standard of a certain imported make” (that would be Mercedes).
The Corvette’s handling was top notch for a front engine car, as long as the road surface was relatively smooth. This was exacerbated by the stiff bias-ply belted wide tires, which provided lots of grip (and very short life), but made for an unpleasant experience when the road became rough or uneven. Radial tires back then had much softer sidewalls, and would not have worked well with the way the Corvette’s suspension was set up. It would take some years and significant suspension re-tuning to make that work, and the radials it eventually came with most likely had stiffer sidewalls.
The four wheel disc brakes in principle were top notch, but due to a less-than ideal rear bias, the tested results weren’t all that great, in terms of maximum deceleration. But the proportioning valve could be adjusted.
The interior was a mixed bag. The huge speedometer and tach directly in front of the driver relegated the other instruments to the periphery. The “improved” ventilation was still quite inadequate. Assembly was actually worse than the ’68 that had been tested. What else is new?
The bottom line was pretty much the same as for all Corvettes: a lot of bang for the buck; and plenty of bangs and creaks and groans when going over bumps. In this case, the bang was even more than usual.
The acceleration times suggest that the big limiting factor in acceleration was traction. Note the 0-100 foot time: Fifty-seven percent of the none-too-startling 0-60 time is spent on moving the first hundred feet!
There’s an interesting contrast here with the July 1969 issue of Car Life, which tested nearly every Corvette powertrain. Their four-speed L71 (also with 4.11 axle and the close-ratio four-speed) returned the following times:
0-30: 3.3 sec
0-40: 4.3 sec
0-50: 5.4 sec
0-60: 7.0 sec
0-70: 8.4 sec
Quarter mile: 13.94 sec @ 105.63 mph
Those times suggest every bit the same difficulties with traction, but the quarter mile trap speed shows that the power was there once you got moving.
They also tested an L89 with Turbo Hydra-Matic and a 3.36 axle. Its acceleration times were:
0-30: 2.9 sec
0-40: 3.9 sec
0-50: 5.1 sec
0-60: 6.6 sec
0-70: 8.4 sec
Quarter mile: 14.58 sec @ 98.57 mph
So, despite the taller axle, the THM car was quicker off the line, and the four-speed didn’t catch up until almost 80 mph. When it did, it left the automatic car like it was standing still. The 7.06 mph difference in trap speed is a lot; not all of that can be attributed to the power consumption of the TH400, so it looks like the wider-spaced gears were just not keeping the 435 hp engine in the meatiest part of its power band at higher speeds.
They ALSO tested an L88, again with THM and a 3.36 axle:
0-30: 3.5 sec
0-40: 4.5 sec
0-50: 5.6 sec
0-60: 6.8 sec
0-70: 8.2 sec
Quarter mile: 14.1 sec @ 106.89 mph
The trap speed makes clear that the L88 (which claimed 430 hp) was more powerful than the 3×2 L71/L89, but all the extra power was on top. (It hit 100 mph in 13.0 seconds, 0.9 seconds quicker than the four-speed L71 car and 2.5 seconds quicker than the L89 automatic.)
For street use, the 350 hp L46 small block matched any of the big block combinations up to 70 mph, and even that was in danger of being clipped by a 340 Mopar at anything short of “spend the night in jail” speeds.
(Car Life‘s 1970 Duster 340 with TorqueFlite did 0-60 in 6.2 seconds, 0-70 in 7.9 seconds, and the quarter in 14.72 sec @ 94.24 mph.)
Thanks for the additional info and context.
I recently found out that originally drag racers only focused on trap speeds, not ETs. In old Hot Rod magazines from the early-mid 50s, they only ever mention ET results. It makes a certain amount of sense, as that is the best indication of hp.
It’s what makes horse races, I guess. A car with less power but better launch characteristics, greater flexibility, and optimal gearing can get ahead of a car with more raw horsepower, and the more powerful car may or may not be able to make up the time within the space of the quarter mile, even if it’s going faster when it gets there.
As for the Hemi, Car Life tested a 1970 Hemi Charger with four-speed and 3.55 axle, which returned 0-60 in 5.7 seconds and the quarter in 13.68 seconds at 104.8 mph — and the Charger weighed over 4,000 lb!
Was the coupe lighter? I hope it would have had fewer squeaks and rattles.
The seats may not have been supportive, but they were more comfortable for chunky mid-life-crisis dudes than most current car seats.
Not really. The AMA specs show only a 5-pound difference between the coupe and convertible.
At that, I am very suspicious of the listed curb weight. The AMA specs show a curb weight of 3,250 lb for a base convertible with the 350. Those specs suggest the minimum curb weight for an L71/L89 with power steering, power brakes, alarm system, and the close-ratio four-speed would be 3,397 lb, which doesn’t include a radio or miscellaneous accessories. The above-mentioned Car Life road test listed the L71 coupe at 3,560 lb and the L71/L89 coupe with THM at 3,505 lb, which seems more like it.
The mentioned poor build quality was a problem with not only the first year C3 Corvette, but the C4, as well, to the extent that those two, specific year Corvettes are the least desirable and, hence, of the lowest value.
IOW, if someone wants to get into the Corvette life for the lowest possible (initial) amount, a base 1968 or 1984 car would be the way to go. Of course, that low price of admission is going to be offset with the myriad issues that will have to be constantly addressed. Old Corvettes, in general, are exactly known as well-built cars, anyway.
I find it pretty hard to believe that a 68 C3 (even a base) is one of the cheaper ways to get into a Corvette. The 75-82s are far less desireable, they never really were.
FWIW, the AMA specs (via https://www.gm.com/heritage/archive/vehicle-information-kits) make me question the text’s assertion that the L89 engine added only 60 lb. Maybe 60 lb over the nose? The specs say:
– L36 427: Add 157 lb
– L71 427: Add 177 lb (meaning the 3×2 engine is 20 lb heavier)
– L89 aluminum heads: Subtract 73 lb
That looks like the L71/L89 is still 104 lb heavier than the 350.
(Admittedly, that’s total weight, not, strictly speaking, the difference in engine dry weight alone, but you see my point.)
The engine sat pretty far back in the Corvette, so maybe that 60 lbs was on the front wheels, but that still seems a bit of a stretch.
As far as I’ve ever read, most iron small blocks are in the realm of 535 lb dry, and the usual figure I hear for an iron 396/427 is about 690 lb, so if the L89 heads saved 73 lb, that would still put the engine in the realm of 610–620 lb (which in this case doesn’t include the additional weight of the triple carburetors and their manifold).
The weight distribution of the Corvette, from the spec sheet, is 50/50. From your calculations, Ate, half of the excess engine weight would be about 60 lbs. In response to Paul’s opening description of the acceleration of this Corvette vs the modern era, with modern tires and a suspension tuned to it, faster speeds are certain. It was an amazingly fast and ridiculous automobile, like a Cobra replica…
In my humble opinion, big blocks belong in big cars and big trucks.
Every big block car I have driven in a smaller car (like a Camaro or Chevelle) was felt overweight and not worth the extra power over a small block.
Many years ago I built an aluminum head .030 over 396 for a guy I knew to install in his Nova. We weighed the engine by putting in his pickup and weighing the whole issue on the scale at the paving plant he worked at. Then we removed the engine, weighed empty and subtracted. I still remember it was 643 lbs fully dressed. Kinda bush league but it worked well enough. I also remember that the heads bought over the counter cost as much as the rest of the engine which was built with premium parts, with the machine work done at the best (most expensive) shop in the valley. Once he figured out how to get the car to hook up and launch it turned low 12s at Spokane. I’m not sure the aluminum heads really gained him much except the “Oh wow” factor when he lifted the hood for someone.
The tri power system used on these 427s, and on the Mopar six pack setup, used a vacuum system on the 2 end carbs and was notoriously tricky to get working properly. It could be done, but a nice big Holley 4 barrel was a lot easier to manage.
From the performance shown here, I suspect this one wasn’t opening enough even at full throttle. Easily remedied, but that kind of thing was not really Road and Track’s focus.
The L89 heads listed for $395 on top of the $437 price of the L71, and the L88 (which Chevrolet really did not want non-racers to buy) was an extra $200 on top of that.
Maybe in 1969 in the US, but by the early ’80s here in the great white north a set of complete heads was about $1500.00 if I recall. I’m not sure if these were still a current item at the time or NOS though. They took awhile to get.
He ran an Edelbrock Torker manifold with a 780 vacuum secondary Holley on the street and a jetted up 800 double pumper on the strip. It was a strong runner!
Oh, I don’t doubt it — I was just saying, even when new, the heads were expensive!
You may already know this, but the entire archive of Hot Rod magazine is now on line at Motortrend on demand. Every issue back to the late ’40s!
The advertising is a hoot, especially the pricing. It’s all relative though, 100 bucks was a lot of money in those days.
The classified ads in the back for the mid ’70s when no one wanted old muscle cars except us gearheads is enough to make me want a time machine!
It should be a little faster than that. I remember seeing an old Plymouth Hemi Road Runner ad in a car magazine saying it ran 13.5 in the quarter mile. A 1970 Buick Stage 1 ran a 13.3. I’m curious about why they left out the top speed.
There are so many variables involved that test results should be taken with a grain of salt. This was discussed once in a Car and Driver article and one of the main things was driver skill, specifically how C&D usually got the best results because of the way they drove the cars, i.e., the old “drive it like you’re mad at it” technique.
C&D would really beat the hell out of the test cars on the dragstrip, routinely using procedures like riding the clutch and power-shifting. The other magazines weren’t quite as rough and their slower results reflected this.
Many of the road tests of this period did not actually measure top speed, usually because they didn’t have access to a track long enough to reach actual top speed and then slow down again (which of course was a project with cars of this vintage). There are some exceptions, but often, there would be no actual top speed (Motor Trend generally went this route) or a calculated or estimated top speed based on gearing.
The editors were not always good about stating this clearly. In this test, for instance, it implies that the 122 mph figure was an observed top speed, which is plausible, but not certain.
Generally, the different magazines had a different enough approach to testing that comparing results between magazines is more or less pointless (even to the extent that the individual tests are valid, which is another matter). Comparing a Car and Driver test to another C/D test might be revealing, but comparing, say, C/D and Road & Track probably isn’t.
Growing up in the ’60’s, Corvettes were one of the Holy Grails of American cars. As a car guy I’ve got a lot of respect for this era Corvette, though I never wanted one enough to buy one, when they were still affordable. When my cousins came back from the Vietnam war, and serving in Korea, they both bought late 60’s Corvettes. One had a big block, the other the 350. Unfortunately they never offered me a ride. Before the Vettes, they both built Harley Choppers. After serving in a war, I feel that they were entitled to enjoy life as much as possible.
The new ones may be faster…
but they don’t have the muscle car era sound.
“Larry Tate” drove one of these on some “Bewitched” episodes.
A ’69 427 Corvette is one of my “If only I had some money” losses in my life. I worked as a emissions inspector in Las Vegas in 1978, and a doctor had a yellow with black interior 427(I’m assuming it was the 390 HP engine) and he was a regular customer. One day he brought it in and had us do a test on it, as he didn’t want any surprises when he sold it. For how much? $3600. The only, and I mean only thing wrong with it was it needed a new top, the sun had pretty much rotted the original. It only had 16K miles on it, and I wanted it badly. I had just bought my totally rotten ’77 Power Wagon 9 months previously, and had little spare cash. I tried mom, a couple of friends, no go. Went to the bank, and they laughed. Bastards. So I didn’t get it. The worst part was the next day it came in, driven by a 17 year old kid, who got it as an early graduation present. As it did the first time, it passed the emission tests with flying colors. A few days later, he got gas and it had a new top. He still had it in 1982, and I wondered where it is today. Did it survive being owned by a young guy? A friend of mine has seen a yellow convertible once or twice and wondered if that was it. Had it survived like my ’74 Roadunner and was now seriously upgraded, or just stock, if at all.