Thanks for the reply. Thinking about the sumping issue last night, it doesn't make sense to me as the back pressure would rob power but would not effect the volume in the cylinder at the top of the stroke. My dyno man actually had the same reaction to using the 258 and suggesting switching out to 251s which, as I mentioned in the thread, was done when the dealership went back in to see if things the cams were aligned correctly. I think they close at 46...and I picked up a couple hp but this didn't solve the compression issue, obviously. It was the dyno man that was convinced something is wrong with the engine and did the initial leak and compression tests. Throttle was open during compression check, don't know the boxes and tops.
It seems to me that with no leakage, the key variables are shape of the piston, shape of the head and stroke length. But the engine couldn't have had the wrong pistons or flywheel installed initially could it? or the wrong heads sent?
leakdown ok, so piston size/rings = ok.
stroke length,rod length, or wristpin location would show up as wrong deck height.
wrong heads? dunno? but when builder cc'd them, he would use formula to determine correct compression for cams---------nuff said there i guess. when i ran calc, i also punched in HD head gskt thickness of .052.
sounds like you are goiiiiing to have to pull heads to get it right. check deck height, cc. if calc doesnt show min of 175 ccp, i wouldnt put it back together till it is corrected.
BTW, a 46 close still isnt a great bagger cam unless you get compression to around 10.5 and it will still come on late. for a 103, about 40 close will make good low end at 9.8 or so.
funny to think this all started because the dealer scared you with waranty. read thiis
http://en.wikipedia.org/wiki/Magnuson-Moss_Warranty_Actand remember, you dont need warranty if job is done right. if job is done at dealer-----better buy extended warranty!!!!!!!!!!!!!!!!!!!!!!