Cam degreeing, what's involved?
Thread Starter
Safety Car
Joined: Sep 2003
Posts: 3,558
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From: Cape Coral FL
Cam degreeing, what's involved?
Curious as to what this involves. I'm putting in h/c in the not too distant future and was curious as to how this is done. I'm assuming you need a timing set capable of it such as SLP or Rollmaster. Is this done at the time of cam install? I thought you needed to match the marks on the crank and cam. Can this be done after the install, say to fine tune the cam for optimum power curve? Any good info would be appreciated. :confused:
Melting Slicks
Joined: Aug 2002
Posts: 2,737
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From: California USA
Re: Cam degreeing, what's involved? (ArKay99)
Look around at this website. This is the where the best LS1/LS6 cams are made anyway. http://<a href="http://www.compcams....Camshafts/</a>
You will need a degree wheel, dial gauge (way to find top dead center as cam is actually in crank degrees), pointer reference and the engine on a stand to do this the right way. Note, I have degreed many comp cams, crane and a few other brands, and almost every one I've checked were within 1/2 to 1 degree of the lobe centers advertised keeping in mind the timing chains are sometimes slack.
Anyway, using a degree wheel/dial gauge, you can actually monitor the opening and closing events of the cam by watching the lift on the dial gauge and the degree wheel. Its also a good time to measure total lift. I always liked this process especially when comparing cams at low lift #s, like 0.2, 0.3, 0,4" etc, gives you a good idea how agressive the cam is. In the end, you can degree it by verifiying the calculated lobe center based on your degree data. A word of caution. Most aftermarket cams already have advance ground in. So make sure you don't change the cam timing without thoroughly going over the cams specs.
ANyway, too many words to describe the process. Try reading the help on comp cams website or maybe its the crane site. ONe of them has a how to degree cam pdf.
You will need a degree wheel, dial gauge (way to find top dead center as cam is actually in crank degrees), pointer reference and the engine on a stand to do this the right way. Note, I have degreed many comp cams, crane and a few other brands, and almost every one I've checked were within 1/2 to 1 degree of the lobe centers advertised keeping in mind the timing chains are sometimes slack.
Anyway, using a degree wheel/dial gauge, you can actually monitor the opening and closing events of the cam by watching the lift on the dial gauge and the degree wheel. Its also a good time to measure total lift. I always liked this process especially when comparing cams at low lift #s, like 0.2, 0.3, 0,4" etc, gives you a good idea how agressive the cam is. In the end, you can degree it by verifiying the calculated lobe center based on your degree data. A word of caution. Most aftermarket cams already have advance ground in. So make sure you don't change the cam timing without thoroughly going over the cams specs.
ANyway, too many words to describe the process. Try reading the help on comp cams website or maybe its the crane site. ONe of them has a how to degree cam pdf.
Navigator
Joined: Dec 2003
Posts: 9
Likes: 0
Re: Cam degreeing, what's involved? (ArKay99)
Ed Iskenderian wrote the definitive book on the subject nearly 50 years ago, "Valve Timing for Maximum Output". If you can't find it, most cam grinders websites have at least an introduction (Comp Cams, Crane, etc.)
However, iskycams.com has a comprehensive tutorial that should get you up to speed, (so to speak).
Advancing or retarding the camshaft in the engine, with relation to the crankshaft, helps the builder tailor power and torque for a specific rpm band, and specific circumstances, i.e. coming off corners of circle tracks, compensating for ambient conditions or altitudes, stickier dragstrips, etc.
Most enthusiasts (and shops) will install aftermarket cams "straight up", although as previously mentioned, many cams are ground with 2-4 degrees of advance, enhancing bottom end performance.
Not many, outside of serious racing endeavors, will choose to dismantle their car just to move the cam a couple of degrees, and shops installing cams won't spend half a day verifying what is already printed on the cam card.
However, iskycams.com has a comprehensive tutorial that should get you up to speed, (so to speak).
Advancing or retarding the camshaft in the engine, with relation to the crankshaft, helps the builder tailor power and torque for a specific rpm band, and specific circumstances, i.e. coming off corners of circle tracks, compensating for ambient conditions or altitudes, stickier dragstrips, etc.
Most enthusiasts (and shops) will install aftermarket cams "straight up", although as previously mentioned, many cams are ground with 2-4 degrees of advance, enhancing bottom end performance.
Not many, outside of serious racing endeavors, will choose to dismantle their car just to move the cam a couple of degrees, and shops installing cams won't spend half a day verifying what is already printed on the cam card.
Racer
Joined: Jul 2003
Posts: 270
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From: granada hills california
Re: Cam degreeing, what's involved? (ArKay99)
To truely find your top dead center and know your exact degrees of retard and advance i degree all my cams, just one of the steps in truely blueprinting a motor. I've had cams off almost 8 degrees before.
