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Does raising the exhuast port effect cranking compression?


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Yes it's useless. Bench testing compression is a joke. A good builder will calculate the compression, then back up the calculations with an actual measurement. (You were told how to do it.) Liquid measurement of the compression volume is 10 times more informative than kicking compression anyway. Kicking compression is the common man's way of getting a close idea of what is going on compression wise. A liquid measurement is the only way to truly do it effectively.

On another topic - if you raised your exhaust port 2mm over that last motors porting.......you just tossed out all your bottom end power and now need a drag pipe to match your porting.

BIGGER IS NOT ALWAYS BETTER.

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I can do the liquid test. I'm not sure how to covert that into a compression ratio. I raised the exhaust port 1.6mm. I brought my cylinder down with a thinner base gasket .010. My squish is at .045 with this combination.

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. Did you try with an impact yet?

 

 

Dude seriously before you keep giving this advice you need to try it on your own quad and see what happens! Some newbie is going to try it and break the end of his crank off!!!!!

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are you sure that isn't his plan for the OP?

LOL ^^^THIS^^^

 

They start top fuel cars from the supercharger belt.

Stands to reason someone would dream up trying a drill.

Try a nice Milwaukee right angle drill. LOL

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LOL I would use a air ratchet if it were me

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^ so I joke and it's fuck me. You joke and it's cool?

 

 

You were joking when you ask him in 2 different threads if he had tried to turn it over with a air gun yet? I call bull shit dude nice try but you were not joking!

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what a joke.

 

how about just put the motor in something and see if it will start..

 

i use cranking comp to check if a motor should run if it wont run.  usually you can feel if comp is to low just through pushing it over by hand.. 

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I did the liquid test. I can get 14cc's of oil into the chamber when the piston is at TDC. I have no idea how to convert that into a compression ratio. I looked online and they want a dome cc height and I have no idea what it is. Lil help here please.

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