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[gremlush]

How does H-D come up with a 9.3 - 1 comp. ratio ?  Myself and 2 other head porters have gotten 93cc on a STOCK 110" head with stock valves. OK. Do the math {or use Bigboys calculator} and with a .040 stock hg that has a 4.020 internal dia. { I just measured my stock take offs}  and 2cc valve pockets in the pistons ,you will come up with 9.72 - 1 comp. or if the heads are 95cc like H-D says ,you will come up with 9.55 - 1 comp.   How do you get 9.3 - 1  AND one more thing ,Andrews grinds the S.E. cams ,and they are not grinding them {255} to the #s listed in the S.E. book. Ask John if you don't believe me. Dewey  ps. you can't hold ,whats not in your hand.

[HDDOCFL]

Dewey ! sounds like it is better with more compresion ?  Doc

[Jbbrown73]

Be careful here.  If HD finds out the compression ratio is actually higher than advertised they will send us a bill!!!

[gremlush]

Book says {S.E. MANUAL} you should have 200-220 cranking comp. with releases OFF. Most people are getting 'around' 216-218 lbs. at sea level.   9.3 - 1 comp ?  come on ,let me hol a 'square' blood. Dewey

[WaSEEG]

How does H-D come up with a 9.3 - 1 comp. ratio ?  Myself and 2 other head porters have gotten 93cc on a STOCK 110" head with stock valves. OK. Do the math {or use Bigboys calculator} and with a .040 stock hg that has a 4.020 internal dia. { I just measured my stock take offs}  and 2cc valve pockets in the pistons ,you will come up with 9.72 - 1 comp. or if the heads are 95cc like H-D says ,you will come up with 9.55 - 1 comp.   How do you get 9.3 - 1  AND one more thing ,Andrews grinds the S.E. cams ,and they are not grinding them {255} to the #s listed in the S.E. book. Ask John if you don't believe me. Dewey  ps. you can't hold ,whats not in your hand.

Uhh, is this good, bad or indifferent?  Assume I don't understand anything about compression ratios and cam grind.  Lay person terms please as I'm on the verge of picking up an '09 FLHTCUSE4.

[Gecko]

Lay person terms: "HD has little knowlege of what they are building."  "The dealers have little knowlege of what they are selling."  "The service technicians have little knowlege of what they are repairing."

[Hoist!]

Lay person terms: "HD has little knowlege of what they are building."  "The dealers have little knowlege of what they are selling."  "The service technicians have little knowlege of what they are repairing."

 

Or none of em could care less. Not sure which? Or both?

Hoist!

[gremlush]

This is from Andrews cams book. They know a little about performance ! { John is freind of mine}  145-165psi. OK for modified street motors  165-185 psi Marginal for large displacement street motors {possible hard starting,detonation,and overheating.} OVER 185 psi HIGH PERFORMANCE #S ,need comp. releases /octane boosters,ETC. {RACING} In my opion , the best thing to do with these motors ,is put a cam in them to 'reduce' your comp. Dewey

[seroadglide]

Whats ccp with that 32?

[seroadglide]

Ops forgot thanks by the way Dewey got it!

[gremlush]

maybe you could post it so all people can see it.  2007 CVO Springer with NO tuning,{black box} just a Zippers air cleaner and slip-on mufflers { I made the baffles ,copy cycle-shack design} have since put on a TFI and a 'little' head work. 102 - 114 now. Dewey

[gremlush]

YES , this was a 'bolt-in cam' and I even used the stock pushrods. Very quiet cam.

[seroadglide]

NOT very good with computers I will have to try and figure it out!!!!

[seroadglide]

here it is

[oldharleyguy]

was told by my local service manager upon picking up my 07se ultra from getting the head enhancement that the compression ratio was lowered from 9.3 to 9.1-2.  WTF!!!