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Is my cam really this retarded???
https://slantsix.org/forum/viewtopic.php?t=45429		 Page 1 of 1
Author:  Griznant [ Sun Jun 26, 2011 12:42 pm ]
Post subject:  Is my cam really this retarded???
I sure would appreciate some help on this. I am putting together a '78 225 with a host of various upgrades. On the cam side, I had the stock mechanical lifter stick reground at Oregon Cam. I'm in the process of degreeing it and can't help but question what I'm seeing.

In a nutshell, I've checked the intake centerline about twenty times and keep coming up with the same number 114.5. Wow, that seems REALLY retarded. From what I've seen around here I want to hit somewhere in the 102 range, and the cam card says that I should have that centerline on the intakes. Since I know their number is relative to the crank in a perfect world, I can only assume that the change is coming via my timing set.

I jumped the cam gear a tooth one way and got 133 degrees, and back the other and got 90.5, so I'm fairly certain this is where it is supposed to be even though the timing marks don't exactly line up dead-nuts.

If it's agreed the number seems correct, and isn't completely unheard of, what's the best method of attack? Drill an offset dowel pin hole on the gear? To advance the cam by nearly 12 degrees relative to the crank, does that correspond to a 6 degree cam dowel change?

Thank you!

Grant
Author:  WagonsRcool [ Sun Jun 26, 2011 1:11 pm ]
Post subject: 
I believe you can drill the pin hole in the cam sprocket oversize. Then use offset bushings for a big block chrysler (summit probably has a bushing kit cheap). 6 degrees should do it.
Author:  stealth swinger [ Sun Jun 26, 2011 1:48 pm ]
Post subject: 
Mine was at 112, i used a drimmel tool to advance it and made a shim
Author:  Dart270 [ Sun Jun 26, 2011 7:36 pm ]
Post subject: 
I thought that one tooth off was 14 deg, but I'd have to count teeth again. Yes, 6 deg on cam gear would be 12 on crank gear.

I would suggest not going higher than 104 centerline, and 101-103 is probably best.

Lou
Author:  Griznant [ Mon Jun 27, 2011 8:22 am ]
Post subject: 
Well, the numbers I got for being one tooth off one way or the other may not have been the best. I checked each one once, realized that wasn't what I wanted to do and really didn't give it a second thought. I was more concerned about the 114.5 and the fact that I rechecked that over and over again, consulted the almighty tome of the internet, and still came up with the same number.

So, I'm going to modify the cam gear. I ran it out in CAD, figured out exactly what 6 degrees would look like, and laid it out so I'm going to mill it today and then fill in the old dowel hole section with either weld or some type of arc-shim.

Thanks for the help! I figured this is what I needed, but wanted to make sure before I did it. :D

Grant
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