Roller LA Deck Height

Bronze Barracuda said

Hi, so getting back to the original question.
What is the deck height of a La Non Roller Bock (9.599)?
A LA Roller Block( )?
Magnum (9.585)?

My curiousity isn't about the final compression as .014 will not be relative to my build. But apparently may have some relevance in the valve train geometry.
I have 1974 LA heads on a 1990 block. I had the pushrod holes enlarged for pushrod clearance, and had the valve spring seats machined for new valve springs I am using the roller pushrods (which are shorter than pre 89 rods) I am trying to gather as much info as I can.
We are taking the block to get dynoed and my mechanic friend figures the deck height will be relevant, I might need different length pushrods.

So after all that rambling, what is the factory deck height of a 1990 360?

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Deck height variance and pushrod length have very little to do with valvetrain geometry on an LA Mopar small block using factory rocker arms. The geometry is fixed since the shaft mounting and the size of the rocker arm do not change. The only thing a longer or shorter pushrod will do is set the plunger preload in a hydraulic lifter.

If the rocker arms are changed to any roller tipped rocker arm the geometry will be off and pushrod length will not fix it.

I do not know the actual deck height and the number is considered nominal anyway since factory tolerances allowed a fair amount of variance in the advertised number. This can be measured precisely by the machinist decking the block or roughly with a larger caliper while engine is apart. No real help since yours appears to be assembled already.