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What do you know about compression readings PSI (pounds per square inch)?
What is a good PSI for a high performance 3 cylinder?
What can you do to increase or decrease the compression?
Do you think the higher the compression the better?
Do changes in exhaust port height affect compression?
Does reducing the size of the cylinder head volume automatically increase compression.
Can a 2 stroke have less than 160 PSI, have a compression ratio of 12 to 1 and require race fuel?
Can higher compression cause the motor to perform less?
Does higher compression increase torque?
Is higher compression more or less important on a high rev application?
Is high octane gas necessary on a 150 to 160 psi motor?
What fuel do you run in your motor?

This is one of many 3 cylinder 2 stroke motor topics I have had limited experience with . I started the thread hoping to learn from others who have experience and success in doing engine modifications.

In a nut shell this is what I know about this topic:
- increasing compression on a stock motor from 120 to 150-165 does improve performance.
- on a stock motor once you get 180 to 220 performance decreases.
- if you have a stock motor with 160 compression and enlarge & raise the exhaust port the compression drops.
- you need a smaller cc volume head with a modified exhaust port to regain lost mid and low range performance.
- higher compression improves the initial acceleration performance from a dead stop
- with motors turning 7700 to 8500 rpm very high compression causes the motor to fight itself . The trueness of the crankshaft and engine balance are important .
- thinking the bigger the better in port size doesn’t normally work without additional modifications to the engine.