Doc,
I got my forged pistons finally but I have a problem. The pistons are flat top. I am building a long rod engine. My compression ratio is 10 to 1. calculated. we figured 0 deck heigth with a 10 cc dish. my pistons mocked up are .075 in the hole the compression ratio comes out the same, but the flat top killed the quench! what do I do? run the piston? or hold out for a dish? I am going to run 100 shot of nitrous. is this thing going to detonate to pieces or will I be OK? how bad do I need the quench?

Unless you welded up the combustion chamber so it is a closed chamber with quench area no flat top or dished piston at zero deck will create a quench combustion chamber. Do you have a closed chamber head?

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Joshua

Unless you have done something special with the head, you will not have quench with any piston that does not stand above the block deck.

Check to see what your minimum clearances are by 'mocking-up' the engine with the head and valves, use clay to see if there is anything running close to contact.
DD

Ok so no quench how about flame travel and effiency? I guess since I am doing a spin off of a 2.2 poston I figured on a dish piston with 10 to 1. If a flat top at .075 thousands in the hole is the same as or close to a dish piston with a 10 cc dish at 0 deck on compression ratio, witch is the better piston?

1 piston in hand is worth 2 in the bush............

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

All else equal, the dished piston is better then the flat top.
DD