Cam Degree Advancement

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Jun 28, 2005 | 08:06 AM

Hvymtlc5

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Melting Slicks

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From: Lake Ozark, MO

Cam Degree Advancement

Is there anyway to tell if your cam is set "advanced" or "retarded" without pulling the engine apart?

Jun 28, 2005 | 08:29 AM

gerry72

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From: San Antonio TX

Not always. First, you have to know what cam is in the engine since you need the specs (intake opening and closing points) and you have to set up a degree wheel to measure the installed specs against the cam card. To run the degree wheel, you need a piston stop and a dial indicator. You can use a screw-in piston stop and you can measure from the lifter seat even if it's a hydraulic. Of course, the easiest way is to do this is with the engine on a stand with no heads so you can use a bore span to stop the piston, a lifter for the dial indicator, and plenty of room for the degree wheel.

So you have to ask yourself, how important is it for you to know if the cam is advance and by how much? And just FYI, most cams are ground with advance in them (the difference between the intake centerline and the lobe separation angle).

Jun 28, 2005 | 08:36 AM

Hvymtlc5

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Melting Slicks

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From: Lake Ozark, MO

Well, while the engine was apart 6 months ago I installed a gear drive. I just "mocked it up" and left it. For some reason I never checked it again before I bolted everything up...just thought about it the other night looking through a catalog......I didn't know the gear drives were degreeable....so I could have set it up 4 degrees advanced or retarded and not at "0".

Jun 28, 2005 | 09:00 AM

gerry72

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From: San Antonio TX

Other things come into consideration (like cam specs, ignition timing, carb calibration) but if it's softer than you think it should be on the bottom end and way stronger on the top end, it may be retarded. If it gives up too easily on the top end and has a robust bottom end, it may be advanced. You could really only tell these things if you altered the timing from a baseline once you tested the car.

Though in your case, you could just pull the timing cover and see where you set it up. If the car is working to your expectations, then you're probably just fretting over nothing.

Jun 28, 2005 | 03:09 PM

Hvymtlc5

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Melting Slicks

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From: Lake Ozark, MO

Quote:

then you're probably just fretting over nothing.

Most likely I set it right way back when...just something I thought about lying in bed going over the daily engine accomplishments and trials for tomorrow type stuff.......

Jun 28, 2005 | 05:11 PM

lars

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From: At my Bar drinking and wrenching in Lafayette Colorado

The engine doesn't have to be torn down to check camshaft installed centerline, but you do have to be able to get a degree wheel on the crank, get a dial indicator to read lifter movement, and be able to turn the engine in a controllable fashion while reading the degree wheel. With an engine installed in the car, this is seldom practical to do, and is difficult at best. You also need to have your cam spec card so you know what you're reading.

If it's a concern, just yank the engine out and set it up on an engine stand to do your cam degreeing - the engine comes out in about an hour and 4 beers.