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Old 10-24-2020, 01:15 AM   #12
Senior Member
Join Date: May 2010
Location: Yakima Washington
Posts: 648
Default Re: Finally some Cam Degree Numbers - Now what?

Originally Posted by Russ/40 View Post
I'm back, and have no idea what I am supposed to make out of the numbers. Here they are. If you recall I have been reluctant to pull the heads, and it was suggested I degree the exhaust valve on number one.

Reconfirmed TDC and very repeatable.
The info I found on the 77B: Int and Exh durations 260* or 220* at .050"
Lobe separation 111*, lift .325* Lash .014".

I got: .050" open at 148*
Exhaust starts to open @ 120.5*
Exhaust starts to close @ 348.5*
Exhaust is closed at 9* ATDC
Exhaust Lash is .014"

Is this enough to get a feel for the cam location? What else need I do. Exhaust centerline?
Russ, A 77B intake opens 19* btdc exhaust closes 19* atdc for a total of 38* overlap. So as Ron says if you split the overlap you're at tdc. Probably the best way to check valve opening and closing is to pull the intake manifold and put an indicator on the cam followers. Then you don't have to worry about valve lash. If when you split the overlap the piston is at tdc the cam is timed correctly.
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