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race cam for straight eight for sale on ebay


Guest buickkuhn

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(Wonder how long it'll take it to attain 7500 rpm?)

Of course, that was BEFORE anything about port flow was known, much less measured accurately. What does it take to make a Straight 8 head have good flow past .350" valve lift? What about the intake and exhaust manifolds to support such rpm? Oh, and carburetion?

Of course, any competent cam re-grinder could make that a pretty neat street cam. Knock some off of the tops of the lobes and shorten the duration a little. What type of pistons would be needed (piston crown design/height) to clear those "mostly open" valves?

Certainly a "relic" of the past!

Happy HO HO HO Holidays!

NTX5467

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And a recommended MINIMUM RPM of 4500 ??

Not my baby !!

Hey Marty,

I know it's not "Kosher" but have you ever given any thought to painting the 1/8" groove in your full length side trim a bright "Chinese red".

With your red wheels, it would really set your car off !

I did it to mine and I have received several nice compliments.post-70733-143142926002_thumb.jpg

Mike in Snowy Colorado

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I suspect for anything over 5000rpm, it would take 4 2bbl carbs (and related special intake manifold) and 8 individual exhaust pipes flowing into a large collector.

By earlier designations, that would be "ultra full race", I suspect. Now, IF you could come up with a viable and fast-acting oil separator, you could use the crankshaft "windage" to serve as a supercharger for the motor, that would be internal and synergistically increase horsepower TWO ways . . . using crankcase vortices being relieved to the intake manifold. With decreased crankcase windage, more power from that, too.

No doubt the "critical rpm" of the connecting rods would be exceeded, so where are the complimentary forged aluminum connecting rods? Other than the crankshaft windage issues, think of the oil flow dynamics of that engine at that rpm level!

Enjoy!

NTX5467

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  • 5 weeks later...
(Wonder how long it'll take it to attain 7500 rpm?)

Of course, that was BEFORE anything about port flow was known, much less measured accurately. What does it take to make a Straight 8 head have good flow past .350" valve lift? What about the intake and exhaust manifolds to support such rpm? Oh, and carburetion?

Of course, any competent cam re-grinder could make that a pretty neat street cam. Knock some off of the tops of the lobes and shorten the duration a little. What type of pistons would be needed (piston crown design/height) to clear those "mostly open" valves?

Certainly a "relic" of the past!

Happy HO HO HO Holidays!

NTX5467

In my teenage years, a friend of mine had a father who raced 1/4 mile dirt track for many years at things like county fairs. His favorite engine to use was the Chevrolet 283 small block, a.k.a. the "mouse motor", which he said was perfect for that application. He had numerous trophies in his basement den to show for it.

When he began to build a street rod as a gift to himself, consisting of a 1948 Ford coupe body on a 57 Chevrolet chassis, he installed a rebuilt 327 Corvette engine in it. When I asked him what custom camshaft grind he installed in it, he looked at me with a facial expression like I was both crazy and stupid. "Factory cam is best!" he exclaimed.

What I learned many years later was that factory design Engineers have to take into consideration multiple factors in designing a camshaft's specs. Most of the time, the specs are a compromise that is optimized for that engine's application, something like a "sweet spot" on the curves of the engine map. Once you go off that optimized sweet spot, you gain something at the expense of something else. Unless you also compensate by making other engine alterations, it will never be as good as what the factory Engineers, with all their sophisticated computer design tools, had in mind.

I don't know who is going to buy this specialized camshaft, but it wouldn't be good for most anyone just seeking to restore the factory performance of their straight eight.

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In many situations, it seemed that Cbevy engineers erred on the conservative side of things. Another part of "the combination" is what do you want the limiting factor to be? A smaller carburetor, restrictive exhaust manifolds, restrictive exhaust system, or internal factors of the engine itself? For a circle track racing situation, mid-range torque would be a factor in coming out of the corners and accelerating until the next corner. A lot of things can vary with circle track racing as many tracks have their own rules on various things, even regional rules, which might not exactly be the same as other regions' rules.

Many tracks have "claimer rules", where anybody can purchase a winner's engine for a set amount of money. This is supposed to orient things toward "less expensive" rather than otherwise. To keep the sport affordable for everybody in those classes. Which generally means "salvage yard parts" in the stock classes. Which could mean that the "best combination" of stock parts, well-finessed, can be a much more competitive engine than you might suspect. Chevy 283s and 327s were an already good "canvas" with which to work. A little carb tuning, a little ignition tuning, a oil pan to keep the oil pickup "in oil", and you're ready to go.

Enjoy!

NTX5467

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  • 1 month later...
Guest 39cent

Gerry Dutweiler's 38 Century straight 8 told me he was over '6k revs' at Ca. antique drags, its stock body, C4 automatic, and ahh, its blown! I tend lieve him.

Edited by 39cent
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Yes, I saw that on an identical (but restored) '37 Roadmaster 80C.

It looked very sharp, but for now I'm keeping mine "All-Original", just the way Flint sent it to NYC for Fiorello's use....

... now, what do you think of the red trim pictured here? The area below the windows is painted the same red as the pin stripes on the wheels of that Buick.

Thanks for the thought,

Marty

post-54863-143143023547_thumb.jpg

Edited by Marty Roth
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