Oilrag,

I cannot get that link to work. I'll try on another computer.

These letters were taken from various Chevrolet Truck Shop Manuals:

Same meanings:
TDC - Top Dead Center
UDC - Upper Dead Center

The B prefix means Before
The A prefix means After

My point is that the ball is not necessarily the same timing specification for different engines, even in the same year.

For example: in 1960 and 1961 (at least), the 235 truck engine's timing specification is 5 degrees BTDC and the 261 truck engine's specification is TDC.

If you had a 1960 261 flywheel, the ball is set at TDC. In that year, there was/is another mark at 5 degrees BTDC (used for the 235).


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edited - added later: this tune-up link works (the final "l" in html was missing):
http://chevy.oldcarmanualproject.com/engine/5560cgt/5560cgt60.html

here is the full-size image of the tune-up specs
http://chevy.oldcarmanualproject.com/engine/5560cgt/images/5560cgt61.jpg


Last edited by tclederman; 01/05/2013 4:40 PM. Reason: Edit Reason: added a correction to Oilrag's tune-up link.
Tim
1954Advance-Design.com
1954 3106 Carryall Suburban
1954 3104 5-window pickup w/Hydra-Matic
The 216 and early 235 engines are not "splash oilers" -- this is a splash oiler.