The Pontiac OHC six is a perfect example of the pitfalls of how GM was organized and run back in the day. The divisions had a fair amount of leeway in certain technical areas, such as engines, but they all had to conform to certain body sizes. That allowed John DeLorean and Pontiac to push the limits of that with two intermediate sized cars: the 1964 GTO and the 1966 OHC Sprint. The first was a runaway success; the second mostly a dud.
That’s not to say the OHC six didn’t have merit per se, or that the Sprint, which was either a Tempest or LeMans with the high-output four barrel version didn’t have positive qualities. But there just wasn’t any significant market interest in a none-too light mid-sized car with a high-output six, not when an equally powerful V8 was available for about the same or less, and it didn’t require an optional four speed manual and high revs to make it perform about the same.
The Pontiac OHC six would have needed a substantially smaller and lighter car to really shine, but in the mid-sixties, that was not about to happen.
There was a lot of hoopla at the time about the first OHC mass production passenger car engine (Jeep’s short-lived Tornado six came out in 1963). Overhead cams were seen as the essential ingredient to a truly modern engine, and in Europe they were becoming more common by the day. The high rpm environment there that the small engines had to deal with made that more expedient. In the US, not so much so. Gas was getting cheaper (in adjusted dollars) every year, and by the time the Pontiac OHC six arrived, it was all about V8s. If Pontiac had been ably to put something like this in their 1961 Tempest, instead of the rough half-a-V8 four, now that would have been something.
Pontiac should at least have had a version of the light Chevy II with the OHC six. That would have been a better pairing.
The Sprint OHC Six, despite all it stripes, was a bit short in several key metrics: handling, brakes and transmission. The suspension settings were the same as the base Tempest six, with a slightly larger front sway bar and somewhat stiffer front shocks. Combined with the numb power steering, it was classic Detroit understeer: squealing front tires were the only real feedback mechanism.
The power assisted brakes were typical of the times: grossly oversensitive to pedal pressure, but yielding scary emergency braking loss of control. And the standard three-speed manual would have been a less-than satisfying match with the six.
R&T assumed that the OHC was just the first step in applying overhead cams to their V8s. Not so. It wasn’t needed, and might have created issues fitting a wider and taller engine under the hoods. And experience would prove that overhead cams just aren’t needed, as the Big Three’s high performance pushrod V8s would prove in coming years and decades.
I had a friend in high school that had one, in a ’69 Tempest. He said “it ran best, a quart low.” To most of us, it was interesting to look at, but that was about it.
I haven’t seen one in decades. If any survived they are probably GTO clones now.
About a decade ago there was one of these in regular use in the Mechanicsburg area. It was the same year and body style as the Road & Track test car. I don’t know what ultimately happened to it, but it was in very good shape at the time.
The OHC 6 was also available in the Firebird, which I believe was Chevy II (Nova) based. It is a shame this engine did not see greater acceptance with the public. The market today does however appreciate a clean Firebird convertible with the OHC 6 judging by some of the asking prices seen in Hemming’s etc.
It was, but the Firebird, which was not based on the original Chevy II, wasn’t much lighter than the Tempest.
The Firebird was 200 lbs. lighter then the Tempest. Less weight, better performance.
No. The Firebird was CAMARO based, not Nova.
Yes the Firebird was Camaro based but, the Camaro was developed in conjunction with the Chevy II Nova that was all new in 1968. All three cars shared the front stub frame, cowl sections and rear suspension systems.
Yes, but the ’68 Chevy II was considerably heavier then the gen1 version. That’s the key element in this.
Wow, until I read this comment I never realized how much heavier the 1968 Chevy II was than the 1962 version. While an additional 310 pounds sounds like a pittance, it’s a 12.65% increase when you’re talking about a car that originally weighed 2,450 pounds.
Still, even at a weight approaching 2,800 pounds it sounds like an X-body with the OHC-6 would have been a bit of a screamer. That’s still 500 pounds less than the Firebird Sprint, not to mention the Tempest Sprint.
Too bad then they didn’t use the OHC 6 for the smaller X-body Ventura. It would have made the Ventura a bit more different from the Nova. Then Pontiac could have also gived the OHC 6 to Olds and Buick instead of having the Chevy 250 for the F-85/Cutlass/Special/Skylark/Century/Regal.
Strange they didn’t studied the possibility to sale the OHC 6 engine to another carmaker like the V6 Buick in 1966 (and GM buyed back later) and the V8 215.
One big obstacle for the Pontiac OHC 6 would have been the FWD application.
Imagine the ’73 and ’74 X-body Ventura with a GTO only Sprint 6 option – and loads of advertising promoting six cylinder economy and 4bbl HO performance just as the gas crisis of ’73 happened. That would have been so much better than the chevy 6s with 100 HP that they did sell.
In 1969, the H.O. Sprint had 230 bhp at 5400 rpm and 260 lb-ft of torque at 3600 rpm. I have no idea what that would have been in 1973.
While we’re at it, they could had offered a stroked version of the OHC six for the Grand Prix and perhaps to the Catalina/Bonneville/Grandville as well as the Canadian Laurentian/Parisienne.
I remember this engine being available in the Firebird, in 1968 (?). When I expressed interest in getting one, my Dad said, “General Motors doesn’t know anything about OHC engines.” End of discussion. I ended up with a 1967 Fairlane GT, 390/3 speed floor shift, silver over red. Sold the car when I got drafted. Missed it ever since.
“my Dad said, “General Motors doesn’t know anything about OHC engines.””
I think your Dad was right – these did not have the best reputations for durability.
No offense to Paw.
I’ve read also that another factor that didn’t help the Sprint 6 was that it was very costly to produce,
Same here. Producing a V8 of similar horsepower was much less expensive, and the buyer could be charged the same amount for the upgrade.
Not all Pontiac Tempest Sixes were the high performance, high dollar Sprint version whose main competition was Pontiac’s own V8. In his superboy crafted COAL series, RLPlaut wrote about his 1967 Pontiac Tempest with the base OHC Six. Against the staid Chevrolet Six, the Pontiac OHC engine did offer a step-up for those who wanted a little better than what the Chevelle offered. But in that market, as among car magazines, that less glamorous offering was largely ignored.
Make that, SUPERBLY crafted! Spellcheck, being syntax-challenged, did that, just as it always changes “its” to “it’s” even when incorrect and unwanted.
I assumed that’s what you meant.
Interesting that spellcheck came up with ‘superboy’ – not a word or even concept I’ve ever felt a need for.
Wasn’t this a Chevy 6 block with a different head?
Basically, but not exactly.
I was going to mention it the other day when the old topic of Different Heads, Same Block began to rekindle, but the embers didn’t catch so I didn’t bother.
Same bore spacing and similar lower-end architecture, but actually unique to the Pontiac OHC. Its camshaft was unique among OHC engines, too. Its bearings were carried not on the cylinder head, but in the valve train cover, that being made possible by utilizing hydraulic lash adjusters instead of using shims to adjust valve clearance, as was the labor-intensive norm in European OHC engines.
Very true. Acura is touting they’re the first to do this in their new twin-turbo V6 in the ’21 TLX. Perhaps they haven’t heard of this Pontiac Sprint engine doing it 55 years ago. Or, let’s be generous, and say perhaps they mean they’re first to do it with twin overhead cams.
The single cam in the Sprint engine meant that the valves were in-line from front to back of the block, meaning an unadventurous combustion chamber shape, pretty much exactly the same wedge as the then fairly new Chevrolet ohv six chamber in fact. Worse, Pontiac decided to mount the intake and exhaust manifolds on the same side of the engine, so the cylinder head wasn’t even crossflow! Or well-ported, if you want to be technical, with all those intake and exhaust cylinder head ports squashed together on one side of the head. Pretty backward for a brand new 1966 inline engine; the Ford Kent ohv engine went crossflow that year. Any V8 is naturally crossflow, and the Chrysler and foreign hemis creatively used pushrods to get that combustion chamber shape, while Chevrolet had the porcupine heads on the 396 racing derivatives using separate ball-stud rockers in a new geometric way.
So the Sprint engine in effect substituted an OHC for the OHV setup and not much else, and never really exploited the lower inertia of the valvetrain to give the engine some decent valve lift, timing, or real increase in revs. It was left to the PR people to make it a magnificent motor.
GM also saddled the slightly later Opel cam-in-head engines with a non-crossflow cylinder head, a busy mechanical thrasher if ever there was one, hydraulic lifters or not. Even Wikipedia mentions this non-crossflow oversight which lasted 30 years. GM Vauxhall in the UK, whose belt driven OHC engine of 1966 was at least crossflow, developed its engine at the exact same time as this Pontiac ohc engine — perhaps nobody at GM’s divisions talked to each other in those days. I’m sure the British would have been baffled at the overly conservative Pontiac design. However, as a counterpoint, the new Audi/VW EA827 engine of the early ’70s was a far sweeter-running engine than all of the above even if it wasn’t crossflow either, proving a decent result could be had if you tried hard enough. I spent five years in Europe in the early ’70s and met these Ford, Opel and VW engines firsthand.
Which all goes to say that the Pontiac OHC engine was an uninspiring thing, a half-hearted effort. 207 hp in a 3420 lb car should do better than 10 seconds to 60 mph. Of course it was SAE gross horsepower, so likely only 150 net, if that. Car and Driver tested a Jag E-type with a Sprint engine substituted for the DOHC six, and it wasn’t near as quick as the original engine, despite being hopped-up. Further, C/D tested a Sprint in Germany on the autobahn and quickly discovered the cooling system was totally inadequate for sustained high speed running.
Sounds like typical GM, then…sizzle with no steak, big budget for styling with no budget for actual mechanical improvement. Any new innovation is strangled in the cradle by bean counters to the point it is somewhere between no improvement and a downgrade.
Yes, they did use the Chevy 6 as the basis on the Sprint 6 engine. YOu could actually use the same distributor from a Chevy 6 on a Sprint 6. I had ordered one for the Sprint 6 which was listed Chevy 6 from Mallory in the 80’s.
A co-worker had one of these in the early 70s, his was a 2 door hardtop, red over white 67. I remember a carload of us bombing all over the streets of Jacksonville. The car seemed fast stoplight to stoplight but we never went looking for cars to challenge.
I often dream of what would have been a real Pontiac Le Mans: a 4 door hardtop with a contrasting roof (either painted or vinyl covered) with bucket front seats, a console, and 4 on the floor…none of that 3 speed manual stuff.
I guess to get a Pontiac like that you had to get a Firebird?
Back in 95 or 96 I had the chance to buy one of these, 3 speed floor shift, for $500. I passed. Kicked myself in the butt ever since.
IIRC, the Pontiac OHC six was borne from DeLorean’s desire for an ‘American Jaguar’. One well-known concept from the time was the 1964 Pontiac Banshee which had the as-yet unreleased OHC 6 under hood (necessitating a significant hood bulge).
Even with the six engine, GM nixed the idea since the Banshee would have likely cannabilized Corvette sales. As it was, the 1968 C3 Corvette looked like a production version of the Banshee.
The irony of the failure of the Pontiac OHC 6 engine is how it would mimic the demise of the Corvair’s turbocharged pancake six; there just wasn’t any room in the sixties for a performance engine other than a V8, particularly a performance six-cylinder engine that was more expensive and weighed just as much as a V8.
Yep, the XP-833. There were two of them. The Sprint 6 and a 326 roadster. If they continued production of the OHC 6, It never would have fit under the hood of the redesigned ’70 Firebird.
Oof! I’m trying to imagine a ’70 Firebird with a hood bulge for the OHC6.
I might just be thankful that never happened!
When I was selling used cars for a Olds dealer in L.A. we took a base ’67 OHC6 Tempest coupe in. I was very tempted to buy it, but even in 1969 the unique engine had developed a less than stellar reputation for reliability.
Based on that, I $old the car instead with a nice gross to a fellow, IIRC, from way down in Orange Cty. Better to make money than $pend it!! 🙂 OTOH, I considered it by far the best looking 66-67 GM A body (still do) and what more could one need than LOOKS!!!! Given that my personal car at the time was a less than visually appealing ’64 Tempest Custom 4 dr. 215 ci 6, uhhhh…..DFO
When I was a kid, our neighbors had a long-term comparison test going on between 2 A body Pontiac 2 door hardtops. The Mrs. had a 66 GTO 4 speed and the Mr. bought a 67 LeMans 4 speed with the OHC 6. When one of their cars started up, there was no doubt which was which just from the sound – I will say that I loved the sound of that OHC 6 as Mr. Bordner did his 1-2 shift in front of our house.
Looking back, there was a lot of insecurity in the U.S. auto industry of that time – guys like DeLorean wanted some of that European vibe and tried hard to get it. The trouble was that while there was much good in that European vibe, it had limited appeal here where European almost always meant “slower and more expensive”.
I love the idea of this engine, but there was just no reason for it here. It would be interesting to see an alternate universe where Chevrolet developed an OHC 6 for the Corvette, in more of a “classic sports car” concept. But with cars like the Corvette and even cars like the Sunbeam Tiger or the AC Cobra, there was simply no purpose for a snobby six cylinder sports car here. You want an OHC 6 in a package that suits it? Buy a Jaguar.
Even in standard 1bbl form, 165hp hauling 3400lbs wasn’t bad for the day @ 0.048hp/lb. The other GM car with a “weird” engine had a (standard) air cooled, 95hp engine hauling 2500lbs, or 0.038 hp/lb. Yeah, the Corvair handled better but the Tempest had more room for the family.
Does anyone know the sticker price of the Sprint option in 1966? How about the 326 2bbl V8 option? Thanks in advance.
I think that most buyers want the most performance for the dollar. Take the Mustang for example. They have always been quite popular with their base six engines. Ford never released a performance version of any of the sixes. They did increase the displacement through the ’60’s from the 170 through 250 cid variations. This was done to restore the performance that was lost through emissions de-tuning. The easiest way to get a faster Mustang was to get a V8, the small blocks could deliver more power with acceptable fuel economy. Not only that, but any hi-po equipment was easier to obtain and cheaper, as well. A.K.Miller was a huge fan of straight six engines and did a series on hopping up the Mustang six for Hot Rod magazine. A mildly modified 289 was still faster.
It wasn’t until the SN95 series that the Mustang gained a V6 that had adequate power. The sixes have just kept getting better, the 4.0 from 2005 -2011 and especially the 3.7 from 2012 to 2015, which produced 300 hp. as well as 30 mpg. And in each case the V6 versions were much cheaper than the V8 models. They are very satisfying cars and for most people paying the premium for the V8 is not necessary.
The first time Ford tried technology instead of displacement with the turbo four SVO buyers voted with their wallets and chose the GT. The current turbo four is much improved as is offered as the base motor.
I like straight sixes, I’ve had several old Datsun Zs, a ’70 Mustang, and even a Jaguar with that configuration. Except for the Mustang, these were the only engines offered at the time, and they were more advanced than the Ford six.
I think that the OHC Pontiac six would have been better accepted in a much smaller vehicle, though GM was not going to let that happen.
I really like the suggestion of the OHC 6 going into the 1961 ‘rope-drive’ Tempest instead of the half-a-389 ‘haybaler’ Trophy 4. In a previous CC, it was suggested that the first Tempest with a good weight distribution (thanks to using the Corvair’s rear-mounted transaxle) could have been a domestic BMW and an OHC 6 version would have cemented that idea. The timing would have been perfect, too, before all the GTO musclecar mania.
In fact, a OHC 6 engine swap into a ’61 Tempest would really be a terrific car-show find.
If only an in-line 6 would even fit in a ’61 Tempest’s engine compartment. Even if Olds, Pontiac and Buick had agreed to the possibility of accomodating an in-line 6 into this body, the resulting weight distribution alterations would have negatively affected handling and would have narrowed any distiction between these and the Chevy IIs
Also, the OHC six wasn’t much lighter than the cast iron Trophy 4. (The 1966–67 230 is probably a bit lighter than the initial 1961–62 version, but not by more than 20 lb, and it’s roughly the same as the 1963 four.) Smoother, yes; more powerful, yes; lighter or more compact, no.
An enthusiast magazine had a project car, a Jaguar E-type to be converted to Pontiac OHC power. Some time into the project had the garage roof fall on it. I do not recall what happened to the project after that.
Seems silly an engine this good couldnt find a home somewhere else in the conglomerate it would have fitted in a Vauxhall Victor nicely their 3,3 litre OHV version was a rocket equally GMH in Aussie could have fitted it to something their cars were performance challenged with less go than the UK Vauxhall 6s this OHC engine was an opportunity wasted.
I had a 66 with a 69 motor 250cid 4.1lit 3 speed 4 barrel. Wish I had put bual exhaust on the split headers. Loved it. Sold it with 140,000 miles, could still chirp 2nd gear. They drove it home.