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Old Jul 19, 2002 | 01:34 PM
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rabidranger's Avatar
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Cam Degreeing

What exactly do you do when you degree a cam? I know it has nothing to do with the ignition timing, but something to do with valve train timing. I thought you could only put the gear on one way for both the cam and the crankshaft and then lined up the 2 marks and called it good. Am I missing something?
 
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Old Jul 19, 2002 | 06:18 PM
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Cam Degreeing

1. check actual duration, lobe separation and lift (important for aftermarket cams as manufacturers and grinders do make mistakes).

2. Check actual cam timing. Most aftermarket cams have 4 degrees of advance built-in to enhance low end torque and many builders like straight-up timing, which will move the power band up in the rpm range.

3. you never know what cam timing you actually have with the combo of chain, sprockets and cam until you degree it. That's why aftermarket performance timing gear sets offer multiple indexes or off-set keys to correct advance/retardation.

As an example, Ford 429/460s from '72 on (don't know when it stopped or if it did) are automatically retarded 8 degrees even when you have the crank/cam timing gear marks lined straight up. This is an emmissions issue. Many rebuilds of these engines don't perform like the owner expected and that's normally the reason.

If you're building any engine, for stock or performance usage, taking the time to degree the cam is important if you want the most bang for your buck.

Hope this helps.


 
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Old Jul 19, 2002 | 11:20 PM
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Cam Degreeing

Also when you get the balancer marks to read zero (TDC for #1), go ahead and look to veryify as a feasibility check that the #1 piston is actually at the top of its stroke. If your balancer isn't marked, it's very helpful to doso, it'll make finding the ignition timing (reasonably) possible in case you get lost. Don't get a timing set that is OEM specs, rather get one that you can verify isn't 8 degrees retarded, it'll pick up your torque and your fuel milage. Cloyes makes OEM spec units as well as strait up timing sets for the same price. Good luck! -TK
 
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Old Sep 3, 2002 | 03:20 PM
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Cam Degreeing

When changing my timing gears on my 86 460, I compared old vs the new Edelbrock set, and my original set was retarded only 4 degrees, not 8. When were they retarded 8 degrees?
 
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Old Sep 3, 2002 | 04:50 PM
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Cam Degreeing

302's were 8 degrees retarded in the late 70's.

'77 F100, 302 (the aftermarket Prodigy), C4
Cadet Second Lieutenant John F. Daly III
South Carolina Corps of Cadets, The Citadel
The TorqueKing
 
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Old Sep 4, 2002 | 12:04 PM
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Cam Degreeing

 
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