my Low dollar 318 hop-up project

318willrun said

As for the stem/guide, I will only measure the amount of "slack", or "slop" the valve has in the guide with the valve off the seat about 3/4 inch - 1 inch. No way does my budget warrant new valves and guides.... Gotta make due, gotta make due!

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All understood .... and I have done the same on budget race engine rebuilds: pull the valve out a way, wobble it, and see what I get. Do you, or anyone, have a rule of thumb on what can be 'gotten away with' on a budget build for valve-guide clearance or 'wobble', or what has worked OK? How much 'wobble' in the valve with it 3/4" out is OK? If it wobbled 1/32" (which is a LOT), is it time to toss the budget heads, or knurl the guides, or ????

I'm not trying to derail the process here, but it would be important IMO to give budget builders a limit to work to on valve-to-guide clearance, and what can you get away with on any clearance: piston-bore, rod or main bearings, etc. It is like the FSM giving new and service limits. A reasonable limit on valve-to-guide clearance has to exist in your mind and build work, or it's a wasted effort and will result in unhappy engine performance.