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Discussion Starter #1
hi guys just want to know why squish is recomended at 1.5mm minimum, would say 1.3 or 1.2mm be okay i know my compression would be higher which is what i want to achieve.cheers paul.
 

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hi guys just want to know why squish is recomended at 1.5mm minimum, would say 1.3 or 1.2mm be okay i know my compression would be higher which is what i want to achieve.cheers paul.
Honda set squish from factory at 2MM to 2.25MM, some I have seen as high as 2.75MM. Depending on your Octane level, Dome CC's, Bore Size, Stroke, Application, ect...you can set your Squish to 1.125 MM to 1.5 MM.

Reason I push UCCR as much as I do is because you can't really tell what you have & need without the UCCR data.

Carlos
 

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Discussion Starter #3
well my dome is 22cc bore 67.5mm squish 1.5mm stroke is standard my uccr worked out to be 12.71;1 and i been running av gas.my cranking psi on gauge is 150psi which i think is low due to exhaust port being large,as you know im machining head to take the start of the squish band/dome out to the 67.5mm.what im concerned about is that i will lower my gauge psi more because i will be taking a little bit more material out of the dome to achieve this,so my thinking was to keep squish abit tighter to maintain a higher gauge psi,or maybe am i placing to much importance on the gauge psi.cheers paul
 

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well my dome is 22cc bore 67.5mm squish 1.5mm stroke is standard my uccr worked out to be 12.71;1 and i been running av gas.my cranking psi on gauge is 150psi which i think is low due to exhaust port being large,as you know im machining head to take the start of the squish band/dome out to the 67.5mm.what im concerned about is that i will lower my gauge psi more because i will be taking a little bit more material out of the dome to achieve this,so my thinking was to keep squish abit tighter to maintain a higher gauge psi,or maybe am i placing to much importance on the gauge psi.cheers paul
Yes, lower the squish to 1.2MM, double check your UCCR numbers, and give it a try.

PS: from experience, and if your bore is round-good & rings are seated; even with a Drag Port Exhaust (very high), at 1.5MM/67.50MM/22CC the cranking compression should not be below 165 PSI. Your Gage may be faulty...

Carlos
 

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Discussion Starter #5
ok thankswhen i get my friend to machine it i will take my quad and ill test my squish and cranking compression in stages as he machines a little bit at a time,with the .25mm gasket which is what i want to switch to (dont trust 1.5mm gaskets i got with steel ring)my squish is .5mm and compression about 195psi but squish will get bigger when he takes dome out to the 67.5 bore.ill test squish at that stage and see what it is along with compression using another gauge,thanks for info just wanted the confidence really to go below 1.5mm clearance cheers paul.
 
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