Pistons: Reverse Dome vs Flattop with dish
#1
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Can anyone explain some of the finer differences?
Also, how much dish is considered a lot for a FI piston, anything over -10cc?
Also, how much dish is considered a lot for a FI piston, anything over -10cc?
#2
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I posted a question a couple of months ago on how much dish could you use to lower the compression ratio. If I remember correctly Diamond said that you can generally the dish volume has to be less than 24cc. I would think that 8-12cc(valve relief size) would be very minimal and 20-24(soup bowl size) would be excessive.
Phillip
Phillip
#3
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John,
From one standpoint I think it's just semantics. A Reverse dome is used to mirror the combustion chamber to get the best burn possible for a compression ratio. Usually a reverse dome is there for low compression race engines, like a 9:1 NASCAR engine or a blown engine.
I would rather have a large dish in the piston and a small chamber to get the compression ratio I wanted rather than a big chamber. It does add weight to the piston, and makes you run a shorter rod sometimes, but it works better for burn.
That's my thoughts.
Bret
From one standpoint I think it's just semantics. A Reverse dome is used to mirror the combustion chamber to get the best burn possible for a compression ratio. Usually a reverse dome is there for low compression race engines, like a 9:1 NASCAR engine or a blown engine.
I would rather have a large dish in the piston and a small chamber to get the compression ratio I wanted rather than a big chamber. It does add weight to the piston, and makes you run a shorter rod sometimes, but it works better for burn.
That's my thoughts.
Bret