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#1777 11/23/03 09:01 PM
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stock49 Offline OP
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Greetings . . .

I was browsing Chevs of the 40s website. They are offering a camshaft reground to '53 Corvette specifications.

Been searching the web trying to find what the factory specs were for the original Blue Flame cam.

Does anbody know these specs or where to find them?

BTW I have written Chevs of the 40s requesting the specs on their regrind. Will post when I get their reply.

Curious.

Stock49


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#1778 11/24/03 12:22 AM
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The 53 to 55 Corvette 235 cam is a very mild grind.It is the same grind used in the 261 truck engine.The 261 engine had 150 horsepower,same as the Vette six without the extra goodies.If you are looking for more performance,go to one of the BIG name cam grinders.Frank McGurk stated 40 years ago that the Corvette cam was a dud and unsuitable for regrinding to hotter specs.
EvilDr235

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Remember EvilDr235 has a cure for Your sixness.

#1779 11/27/03 09:03 AM
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Try a rumpy Howard`s cam (Patricks) or one of Tom Langdons Bulldog cams. They have different lobes on the intake and exhaust.

what you get is close to the cams Frank Mc Gurk developed and the best compromice between power and idling.

Frank

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#1780 11/27/03 11:25 AM
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Here's a link to a site with stock cam specs for Chevys, http://www.engineparts.com/Motorhead/techstuff/stockcspecs/chevrolet.html
I run a mild Howard's M4F in a 261, fairly smooth idle, makes more power than the stock 261 cam (Corvette) from idle to redline, it has 206 degrees duration at .050 lift and around .421 valve lift


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#1781 11/30/03 12:29 AM
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stock49 Offline OP
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Thanks Frank . . .

I am familiar with both the M4F and F298 grinds from Howards. Both of these are for the 235. I am building a 216, so the options are fewer.

I have been considering regrinds. The guys at ISKY said they would re-grind a 216 cam to any spec I like within the limits of what is left on the base circle.

I would really like to lay my hands on a Howard SU9A 'super' grind. But they haven't been made in years. My best bet is to find one laying around in someone's garage.

I guess I will inquire at Langdon's to see if he has a Bulldog grind for the 216.

BTW, I have seen your website before -- I particularly like the shots of the '41 taken in Germany and magically transported to Texas! Nice work.

Where are you located? I work for the American subsidiary of a German Software Company located south of Heidelberg. I travel to Germany at least once per year. Look forward to every trip.

gruess,
Keith


[This message has been edited by stock49 (edited 11-29-2003).]

[This message has been edited by stock49 (edited 11-29-2003).]

[This message has been edited by stock49 (edited 11-29-2003).]


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#1782 11/30/03 12:40 AM
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stock49 Offline OP
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Thanks Tony P . . .

I am familiar with the page referenced in link that you have provided. So the specs on the 261 are what was done for the original Blue Flame. . . interesting.

The regrind being offered by Chev's of the 40's got my attention as I am trying to assess all my options before I start to do the rebuild on my 216. I really want to do something beyond the stock cam. I already have a set of Barker Hi-Lifts -- so I really only need help in the duration department :-)

Here's some pics of what I am starting off with: http://home.mindspring.com/~vwariff/

stock49


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#1783 11/30/03 06:43 PM
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stock49 Offline OP
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Hey Tony P & EvilDr235. . .

I just had a closer look at the specs on the cam for the 261. 290 degrees of duration? Isn't that 'Stage III Tuning' according to Tom Langdon? Or is this a misprint?

I was comparing these numbers with the valve timing diagrams from California Bill's book . . . his digrams of a 'Super Grind' show a duration 288/int and 285/exh . . . back then cam discussions were valve-open to valve-closed duration (SAE) correct?

Am I perhaps mixing .050 and SAE specs when comparing these cams?

If the table is correct, the 261 cam has only 190 degrees of intake duration above .050 -- but there is an additional 100 degrees of duration that is shallower than that. This makes for shallow ramps running up to and off of the lobe center - a design that is easy on push rods and lifters correct?

As such, I thought that these .050 specs just helped one to see how steep the cam profile is.

Isn't duration duration?
The valve is open . . .


[This message has been edited by stock49 (edited 11-30-2003).]


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#1784 11/30/03 09:54 PM
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stock49,you do know the 216 has smaller bearing journals than the 54 and later 235 and 261 engines.Be sure to use a steel cam core for your regrind.The cam will last a lot longer than a cast one.
EvilDr235

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Remember EvilDr235 has a cure for Your sixness.


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