Modular Revolution Forums

Modular Revolution Forums (http://www.modularrevolution.com/forums/forums.php)
-   Tech Articles (http://www.modularrevolution.com/forums/forumdisplay.php?f=8)
-   -   Cam degree article (http://www.modularrevolution.com/forums/showthread.php?t=17200)

nickmckinney 10-25-2009 11:09 AM

Cam degree article
 
Cam degree article, please critique.

MHS article on cam degree

Bill Putnam 10-26-2009 05:22 PM

Looks good Nick.

On step three how do you know when the adjustable lifter has been adjusted properly? In other words do you have to watch the valve spring to make sure you aren't compressing it while taking up the slack with the adjustable lifter?

Bill

nickmckinney 10-26-2009 05:38 PM

I adjust the lifter until the valve is 0.001" compressed as shown by the dial indicator. With cam degreeing only it doesn't matter to be honest. It would matter for QC of the opening and closing points of the cam is all.

nickmckinney 02-05-2010 01:45 PM

Well after really doing a bunch at one time I have learned the cams have more issues than the gears. I just did a set of cams that were supposed to be 110 and found 102 and 112. The 102 of this monster cam had the valve into the piston even with a piston notch. I am now offering degreeing of your cams in house as a result. Even the OEM cams vary a few degrees. What a biach.

frozenphil 02-05-2010 04:16 PM

How would you go about degreeing them in house?

nickmckinney 02-05-2010 06:23 PM

Quote:

Originally Posted by frozenphil (Post 45490)
How would you go about degreeing them in house?


They would get installed in this blueprinted motor:

http://www.modularheadshop.com/Artic...s/100_2303.JPG


That is its only function anymore, to install and test the install centerline of cams.

Ed Galanda 02-05-2010 06:58 PM

Quote:

Originally Posted by nickmckinney (Post 45483)
Well after really doing a bunch at one time I have learned the cams have more issues than the gears. I just did a set of cams that were supposed to be 110 and found 102 and 112. The 102 of this monster cam had the valve into the piston even with a piston notch. I am now offering degreeing of your cams in house as a result. Even the OEM cams vary a few degrees. What a biach.

Damn that was off alot.

frozenphil 02-05-2010 06:58 PM

I may have gone full retard because I'm not understanding how you're able to sell them degreed. I'm assuming that you only offer this service if someone purchases heads from you or send in their own heads to have degreed. Can you degree a cam inside the head and ship them that way, already degreed? How do they stay degreed when installed on a new engine?

nickmckinney 02-05-2010 07:12 PM

The degree fluctuation is primarily in the cam keyway location and the cam gear. We have a test motor that is blueprinted and repeatable that we can install any 2V cam on and test it to see how far off it is. You can then move it and the matching cam gear to another motor and typically be within 1 degree of this test motor. If your heads and/or block is decked its an additional -0.5 degrees for every ~0.008" that was removed.

96SOHC 04-04-2010 06:46 PM

Quote:

Originally Posted by nickmckinney (Post 45501)
The degree fluctuation is primarily in the cam keyway location and the cam gear. We have a test motor that is blueprinted and repeatable that we can install any 2V cam on and test it to see how far off it is. You can then move it and the matching cam gear to another motor and typically be within 1 degree of this test motor. If your heads and/or block is decked its an additional -0.5 degrees for every ~0.008" that was removed.

That makes sense. Just attempted degreeing the new Stage 3 cams in...my heads are shaved .050", which equates to -3.0 degrees retarded. Plus, the block was zero decked (about .015" removed from the surface), which equates to another -1.0 degree, for a grand total of -4.0 degrees retarded.

My question is if you are facing the front of the engine looking at the cam gears, do you rotate them clockwise, or counterclockwise to advance the cams?

If I use the Trick Flow adjustable crank gears, same thing...clockwise or counterclockwise to advance the cams? The crank gears are marked, but are confusing to me. For those unaware, take a look on Nicks website (cam degree article) to see all the numbers on the gears.

One other question...if I choose to move the chains one link forward or backward instead of lining up the dots, how much would that equate too?


All times are GMT -4. The time now is 11:24 AM.

Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2010, Jelsoft Enterprises Ltd.