Is Degreeing In a Cam Necessary?
#1
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Is Degreeing In a Cam Necessary?
Is it necessary to degree in a cam, or can you just throw it in "heads up?" I always thought that you used a degree wheel if you wanted to install the cam a little bit advanced/retarded.
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Re: Is Degreeing In a Cam Necessary?
Degreeing a camshaft is double checking the manufacturers specs. It can also correct any misalignment specs in your engine such as timing chain slop.
I installed my cam straight up and the only thing I checked was to make sure the timing mark was accurate when the piston was exactly at TDC.
If you degree the cam and find out it's off a bit, you can correct it with a crank gear that has multiple keyways or with offset bushings in the cam gear. The crank gear with 3 keyways allows 4* advance or retard. If you require more or less than that, you need to use the offset bushings which allow 1* at a time. I wouldn't recommend the timing sets with more than 3 keyways on the crank gear.
For the majority of people, installing it straight up is the easiest and won't cause any problems. Advancing or retarding the cam, you need to recheck the piston to valve clearance because it changes when the valves open and close in relation to where the piston is in the cylinder.
Many cams already have advance ground into them.
Advancing a cam moves the HP curve downward slightly. Retarding a cam moves the curve upward slightly. It doesn't change the peaks. Advancing a cam increases torque and retarding a cam decreases torque.
So...
Advancing decreases peak rpm of HP but not HP itself and increases torque
Retarding increases peak rpm of HP but not HP itself and decreases torque
We're not talking about huge numbers with a typical 4* +/-
I installed my cam straight up and the only thing I checked was to make sure the timing mark was accurate when the piston was exactly at TDC.
If you degree the cam and find out it's off a bit, you can correct it with a crank gear that has multiple keyways or with offset bushings in the cam gear. The crank gear with 3 keyways allows 4* advance or retard. If you require more or less than that, you need to use the offset bushings which allow 1* at a time. I wouldn't recommend the timing sets with more than 3 keyways on the crank gear.
For the majority of people, installing it straight up is the easiest and won't cause any problems. Advancing or retarding the cam, you need to recheck the piston to valve clearance because it changes when the valves open and close in relation to where the piston is in the cylinder.
Many cams already have advance ground into them.
Advancing a cam moves the HP curve downward slightly. Retarding a cam moves the curve upward slightly. It doesn't change the peaks. Advancing a cam increases torque and retarding a cam decreases torque.
So...
Advancing decreases peak rpm of HP but not HP itself and increases torque
Retarding increases peak rpm of HP but not HP itself and decreases torque
We're not talking about huge numbers with a typical 4* +/-
#4
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Join Date: Jul 1999
Location: 51°N 114°W, 3500'
Posts: 17,166
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Received 136 Likes
on
114 Posts
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: Is Degreeing In a Cam Necessary?
Read this to see why I never bothered to degree my cam.
http://www.dragracingonline.com/tech...sion/ii_4.html
http://www.dragracingonline.com/tech...sion/ii_4.html
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