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Compression reading in respect altitude.


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Hey guys i have been doing a lot of reading and problem solving since i received my cylmer and for the most part im feeling pretty good about what ive learned.

i do have a question that i cant seem to make sense out of reading endless threads looking for a specific answer, or even ballpark answer.
i know no one can tell me with 100% positivity what i need to run, but some shedded knowledge would be nice.

i went out and bought an actron compression test gauge, got the tank off. much to my surprise both cylinders were 165 psi -/+ it was hard to tell exactly with bench marks between 150 and 180lbs. slightly under the half way mark (165) 
that determains the head was milled. Im also now under the impression there is no port work done. (previous owner flat out told me it was all bolt ons, even stock head he swapped out for his friends milled head.) 

 

From my reading i understand that you need more shaved off the higher up you go to achieve the same compression reading. and you need to adjust your squish in respect to how much you shaved off.
My concern is does squish need to be adjusted in relation to evalation? Ex. if he was running lets say 150psi ??, at 3000 ft/asl, and now im at 165psi at 1000 ft/asl, does mean i need to run higher than 93 oct? do i need to worry about the squish not having enough tolerance? Im looking for the safest, cheapest way to have a reliable machine. Hell, even if i need to just get a new unmodded head i would rather do that then not having some peace of mind. 

On my first thread, loco recomended 270-290 mains and 27.5 pilot. i went off that and ended up going 300 mains and 27.5. it is running rich, but from what ive found in other threads its not a bad idea to run rich with higher compression on pump fuel. 

Yesteday when i ordered toomey spark arrestors i ended up asking stuart toomey for the hell of it some advice on jetting. i told him my Compression, mods, evlivation change, what prevoius owner had (270 and 25 jets) he told me i am running way too rich...he said 280 and 25 pilots. 

other info: jetted for 65-90F, 45-65% humidity (very humid summers here in wisconsin) 1000ft /asl. Running 93 oct 32;1 castrol 927. stock timing. crank is stock, (cant remember if he said it was trued and welded, hoping so.)

 

So thats where im at. 

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