Rick has one of the finest mechanical minds on this planet, i never take offense.
If the truck engine does not have the internals of a marine engine, how you going to use marine engine specs ?
MM, first.... thank you.
Secondly..... you're not a dummy for having suggested that.
All I meant by my comment was to caution anyone from setting Marine Engine ignition timing by ear. We may be only a few degrees away from causing detonation. That is the risk, IMO.
As for the truck engine internals, I don't have the same issues with the cam profile, per se', as I would with combustion chamber design.
GM loves the full dished pistons, whether Marine or Auto.
However, when I do a search re; the 4.3L, I come up with both Full Dished and F/T's. It would be helpful to know which pistons were used.
The full dished pistons offer very little in the way of preventing detonation...... in fact, this piston actually promotes detonation if we aren't conservative re; ignition advance.
So, whether Marine or Auto built, I'd use the Marine timing specs for this engine in a Marine application, and avoid the risk of detonation damage.
duckhunter185, there must be a TDC mark somewhere at the front of this engine. It may be a single pointer.... I don't know.
Can you post photos?
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