According to some reading and using this utility using 40cc as the "Head Chamber Volume" and FLAT piston:
http://home.quixnet.net/~cosmic/EngineCalc.htm
I came to the following conclusions:
OEM
95mm bore x 61mm stroke = 432cc @ 11.8 compression ratio
450 Kit - "so called"
96mm bore x 61mm stroke = 442cc @ 12.05 compression ratio
450 kit, not legal
97mm bore x 61mm stroke = 451cc @ 12.28 compression ratio
460 kit monster
98mm bore x 61mm stroke = 460cc @ true 12.5 compression ratio
This makes sense to you guys?
Compression Ratios and Bore Sizes - The Truth
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Dont know the actual particulars for each of those examples but I do know a little change in any of the info punched into a comp calculator will make a noticable difference in the resulting comp ratio.
If its just a little off in the deck height, piston dome, head volume or the gaskets are a couple thou thinner when compressed it can throw things off.
One thing is that you guys should be happy since it doesnt seem wiseco screwed up with the c-dale pistons like they did on the EX cause some of the big bore 10.8:1 kits were under 9:1 actual.
If you cant or dont want to actually cc your engine to get the actua comp those calculators are great!!
If its just a little off in the deck height, piston dome, head volume or the gaskets are a couple thou thinner when compressed it can throw things off.
One thing is that you guys should be happy since it doesnt seem wiseco screwed up with the c-dale pistons like they did on the EX cause some of the big bore 10.8:1 kits were under 9:1 actual.
If you cant or dont want to actually cc your engine to get the actua comp those calculators are great!!