Thread: GP 1200 compression question
07-01-2009, 08:39 PM #1
GP 1200 compression question
Just bought a Cool Head by Pro design for my 99 GP1200 npv. I'm trying to achieve the 140psi to 160psi range. The head came with 30cc domes said to bring me up to 215psi. Does anyone have any input to what size domes I should get to achieve my desired compression? By the way the engine is a stock bore 1200 non pv.
07-02-2009, 07:37 AM #2
On my ada head, 42cc domes put me around 150psi range. I would guess it would be the same for the Cool Head.
07-02-2009, 01:27 PM #3
07-02-2009, 06:48 PM #4
Pro tec and Pro design domes
Pro design 150 psi 44cc
Pro tec 150 psi 42cc
Dont ask me why all I can figure is they measure them diferently.
I have Both heads and domes are interchangeable from one to another.
07-02-2009, 08:39 PM #5
07-02-2009, 08:50 PM #6
34cc215psi200psi 36cc195psi185psi 38cc185psi170psi 40cc170psi160psi 42cc160psi150psi 44cc150psi140psi
$40 a pop
07-02-2009, 09:21 PM #7
07-03-2009, 07:54 PM #8
- Join Date
- Sep 2008
- Clarksburg, WV
I thought the 99 had the powervalves
07-04-2009, 11:58 AM #9
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