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[Daniellee]

I'm going to use the 117 kit in my 2016 CVO Pro Street Breakout. I need to reduce the combustion chamber to 90cc to get 139 :1 static compression. With the 259e cams - corrected comp is 9.26:1 with 192.2 cold crank comp. Does anyone know how much I need to mill the heads to achieve this?
What do think my numbers will be...

[grc]

I'm going to use the 117 kit in my 2016 CVO Pro Street Breakout. I need to reduce the combustion chamber to 90cc to get 139 :1 static compression. With the 259e cams - corrected comp is 9.26:1 with 192.2 cold crank comp. Does anyone know how much I need to mill the heads to achieve this?
What do think my numbers will be...

You're going to need a much bigger starter and battery.

Jerry

[HD Street Performance]

I'm going to use the 117 kit in my 2016 CVO Pro Street Breakout. I need to reduce the combustion chamber to 90cc to get 139 :1 static compression. With the 259e cams - corrected comp is 9.26:1 with 192.2 cold crank comp. Does anyone know how much I need to mill the heads to achieve this?
What do think my numbers will be...

These questions pop up a lot
No way of knowing without fluid measurement and cutting in steps.
So where are yours, to begin with, could be 96+ all the way down to 92cc is what I have observed after measuring well over 100 sets.

[grc]

Btw, I noticed you posed the same question in another thread.  If you're looking for a precise number you won't get one, since the stock combustion chambers vary in capacity and the deck heights also vary.  Since you have the air cooled heads and not the water cooled version, at least you don't have to worry about the water jacket issue.

IMHO the best approach is to first get the deck heights right, then check both heads for combustion chamber volume and have each one set to your desired volume.  In other words, blueprinting versus "close enough for government work".  We have some head experts on this site, some of whom posted in your other thread.  They didn't give you an exact number to mill the heads for a reason.

Jerry

[Daniellee]

Thanks for the info.  I appreciate it..