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Discussion Starter #1
Hi friends,

I’m getting ready to install a new cylinder head and noticed all the exhaust cam lobes are a few mm out of alignment with the buckets. The intake cams are dead on centre.

I know the buckets are meant to spin to create an even wear pattern, so maybe being offset is intended.
1605963

I maybe I shouldn’t worry but it seems strange that the intake lobes are not offset.

Anybody know if this is a problem?
 

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Here is what I would do. Remove thew front upper cap. Replace it with ANY other front cap, you don't need to snug it down. If the cam must move back for that to fit, your cam has wallowed out both the front lower saddle in the head, and the cap. There IS a big issue as to how that might happen as the other cam, idler sprocket and chain tensioner ALL conspire to center the lobes on the follower, particularly running.
Compare the thickness of the Ex cam front collar to the intake cam collar. Possibly someone has "re-surfaced" it for who-knows-what reason.
The cams tend to center off the chain sprocket, because running, all the sprockets tend to run in line.
Something IS wrong here. There is axial play, but not that much axial play.
 

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Discussion Starter #4
The intake cam cap fits just fine. There doesn’t seem to be any slop in the journal.
Also, the sprockets are only about 1mm out of alignment, vs the cam lobes which are 2-3mm out.

so it seems to be all fine except for the off center lobes.
 

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Discussion Starter #5
Whelp. Had the only free day between now and Christmas, so head and cams are in the car. Will post updates if the wear pattern or play changes noticeably for the benefit of other BBers
 

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It is normal for cams with conventional flat followers to have the lobes offset on the face of the follower to rotate the follower for more even wear.
 

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With Alfa's .03mm is enough to spin the bucket. You do not need 3mm!
 

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the tappet bore looks notched for lobe clearance.

and the oil drain slot looks modified too....I have not seen that one before....any reason?
 

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Racer trick to keep from making a mess R & R cam cover with a hot engine. Running, it keeps the oil DOWN where you need it rather than pooled in the head. Not really a necessary modification, and a "V" groove serves as well if you want to do that.
 
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