How do Cam bushings work?
How do Cam bushings work? I was advised to use "cam bushings" to compensate for my cam being 6* advanced.
I know what they look like from the summitracing pics, but I don't understand
how they work. I don't see 3 boltholes, it looks like a single funky off-center
hole. And it needs a drillbit?
I'm lost.
I know what they look like from the summitracing pics, but I don't understand
how they work. I don't see 3 boltholes, it looks like a single funky off-center
hole. And it needs a drillbit?
I'm lost.
TECH Fanatic
Joined: Jun 2002
Posts: 1,979
Likes: 3
From: Upstate NY
Originally Posted by James Montigny
I was advised to use "cam bushings" to compensate for my cam being 6* advanced.
I know what they look like from the summitracing pics, but I don't understand
how they work. I don't see 3 boltholes, it looks like a single funky off-center
hole. And it needs a drillbit?
I'm lost.
I know what they look like from the summitracing pics, but I don't understand
how they work. I don't see 3 boltholes, it looks like a single funky off-center
hole. And it needs a drillbit?
I'm lost.
If the cam dowel pin is .250 diameter, so is the "funky" or offset hole in the bushing. If you drill out the the dowel pin hole in the cam sprocket to the outside diameter of the bushing, you can then advance or retard the cam by locating the offset hole in the bushings one way or the other.
If the dowel pin is on a .580 radius, each degree is just about .010, so a 4 degree offset bushing would have the .250 hole offset about .040. A bushing kit might have a 6 degree offset bushing, a 4 degree, a 2 degree and a zero degree (concentric) bushing so you could install the cam 6 deg. advanced, 4 deg advanced, 2 deg. advanced, straight up, 2 deg. retarded and 4 deg. and 6 deg retarded depending on which bushing you used and what direction you put it in.
If this is an LT1 with Opti you might want to check what happens to the ignition timing with offsetting the cam.
Clear as mud?
Originally Posted by ToxicTA
Are you getting the 6* advance from a degree wheel or is the cam being advertised to have the 6* advance designed into it.
Launching!
Joined: Apr 2006
Posts: 218
Likes: 0
From: Central Wisconsin
This is just off the top of my head and anybody feel free to correct me but in my case I have a Lingenfelter Spec'd Mechanical Roller cam and the cam is ground I believe 4* advanced just to keep you from having to use any type of after market button.
I saw a note in Comp's install manual that said everything is ground 4* advance
to make it more usable in street applications. *shrug*
I was told to degree it to 0*, so I did
Runs great
to make it more usable in street applications. *shrug*
I was told to degree it to 0*, so I did
Runs great
