Sitting down? Maybe you should.

Steamer said:
Thanks Bob. I would have thought that the tri power setup would be more powerful. Guess it must be the 12 to 1 comp, bigger cam, headers and side pipes that make the real difference!
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The differences are "Can-Am spec" aluminum heads with much larger valves (2.19-inch intake and 1.84-inch exhaust), strengthened crankshaft, 12.5:1 compression forged pistons with special full-floating pink rods, a .540"/.560" solid-lifter camshaft, an open-plenum dual-plane aluminum intake, an 850 Holley dual-feed carb, and cold air induction via a different (and extremely rare) big-block hood. Required a minimum of 103 octane fuel. No fan shroud. No heater/defroster. No choke. No radio. No A/C (of course LOL). No automatic (in '67). Difficult to start when cold, but then....oh baby!

There were plenty of mandatory options as well. Special heavy duty brakes. Special suspension. Special M-22 4-speed. Special K-66 ignition. Special cooling....yada, yada, yada.

Under-rated at 430 hp. Easily produced 560 through headers, and a little tweaking pushed it well over 600. Why under-rated? That's easy. It was for people like me who wanted the biggest horsepower numbers on the order sheet. Why settle for 430 when you can have 435? Truth is, unless you somehow knew about this late-in-the-year option, you wouldn't be able to order it anyway. Chevrolet engineers did NOT want this car on the streets. It was intended for a specific use, and cruising the A&W wasn't it. LOL

After all was said and done the L-88 pretty much doubled the price of a standard Corvette.

Oh, and just to add some confusion to the mix, the L-88 wasn't the only '67 Corvette to get aluminum heads. The other one is even rarer....but that's another story.

:D
 
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Bob, Thanks for filling in the blanks about these motors. Unless your in the know, there is lots to learn about them. I can still remember my first ride in a corvette and it was an L88 owned by my friends brother Terry from Guelph. He had already installed a five point harness and I remember being buckled in and told to keep quiet and hold on. That great experience stuck with me to this day and I still get the same feel riding in my own Vette.
Can't wait to here about the other one.
Thanks Rob
 
Bob, thanks for posting this ... Please keep 'em coming , I find this stuff very interesting ! :)
 
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As you can see, the L-88 engine and the M-22 transmission weren't listed in the Fall '66 printing of 1967 Corvette options...
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You're looking at the business end of one of the rarest Corvette pieces in existence.

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A real 1967 L-88 hood, from the driver's perspective. Those slots are how cowl induction happened on the big block stinger hood.

The suction was sufficient to pull in any stray Mustangs that happened by.
 
I read an article many years ago about the L88. It was my understanding that the long duration cams don't like back pressure and really suffered. In the article, the guy said that the car gained so much power that he wouldn't even give the number because no one would believe him. The 430 hp might just have been not that far off as delivered from the factory. Like our old 427, these engines had to meet emissions standards and that really killed them too. Extremely lean primary jetting and a retarded, slow advance curve killed off a lot of power. The good news is that with some patience, jetting and timing could be figured out bringing a lot of the lost power back without spending a boat load of money. Headers and good exhaust did the rest. I know it made a big difference on our old Chevelle. A mechanic couldn't figure why mine ran so much better than a friend's identical car. Today, you can just put the car on a chassis dyno and get it dialed in pretty quickly. Not the case back then where I come from. For the guy who knows his way around engines, there is nothing like the L88 or ZL1. If you didn't know your way around, they wouldn't be much fun at all. They were basically race cars. I remember a guy I worked going down to Ontario Motor Sales to buy a ZL1 Camaro to blow all of our doors off. He came back with his tail between his legs. The engine option cost more than the car putting it right out of his budget.
 
Keith Tedford said:
I read an article many years ago about the L88. It was my understanding that the long duration cams don't like back pressure and really suffered.
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Yes, Keith. It's generally accepted that adding a well-designed set of open headers to any special-high-performance or heavy-duty big block generates an instant 75 additional horsepower.

Another problem with the long duration cams on these engines is the alarming absence of vacuum for the power brake booster at low street speeds. Most power brake systems prefer at least 15 inches of manifold vacuum, easily supplied by most stock cams at idle. Engines with long-duration cams keep the valves open a lot longer, resulting in idle-vacuum readings way under 15 inches of mercury. It almost feels like the brake booster isn't working.

Another reality is the stumble off-the-line at stop signs/stop lights when trying to pull away at normal (reasonable) rpm levels. The big guns just hate that low rpm stuff. :rofl:

The lesson here is to launch big or stay home. LOL

:seeya:
 
was that engine offered in limited production to meet nascar requirements ? sort of a hemi fighter like ford did with the boss 429. i believe somewhere around 500 of the boss motors were produced most going to race teams, a few made their way into funny cars. apparently it's unknown if any went into a production car, nascar ended up disqualifying the boss engine. anything like this happen to the chevy ? back in those days when the factories were throwing support behind teams things got a little nuts, pontiac was even working on a hemi motor.
 
buckhorn76 said:
ouch ! careful bob, the ghost of smokey yunnick might come to haunt y'all !! :eek: :rofl:
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Rather than a few hours of roundy-round, turning left, the L-88 was developed to run the 24 Hours of Lemans and the 12 Hours of Sebring where cars also turned right, braked, hard-cornered and generally demonstrated their overall worth as a fully-functioning vehicle in all kinds of weather.

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1963 Corvette Grand Sport

THIS is racing. ;)
 
Then there was the big bore CanAm blocks in '69-'70. The bigger bore let the engine breathe a little better by unshrouding the valves a little more. Guys like Jenkins latched onto these for Pro Stock racing. They could be made into some big cubic inch engines. 494 CID comes to mind. A couple of friends have built 496 stroker motors from their 427s and 454s. I haven't ridden in either but will this summer. This winter the local guy is adding a Keisler SS700 to his for some shifting fun and decent cruising rpm. http://www.keislerauto.com/Keisler_Auto/Keisler_Engineering.html
 
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some of the displacements have become gigantic, over 800 ci. with aftermarket blocks. what is truly mind boggling is the top fuellers and funny cars have a 500 c.i. limit and produce 8000 or more horsepower.
 
Well, this has been a good day. Lots of interesting feedback and old memories to help forget February outside the window. Mind you, I did play too much today, and didn't get nearly the work done that I had intended. Oh well, there's always tomorrow.

Speaking of tomorrow, I wonder what this belongs to?
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Maybe we'll find out tomorrow.

Meanwhile, rather than counting sheep - Lullaby and goodnight.

:seeya:
 

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