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1G Low compression new engine

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By chance does the motor have cams? cams with a lot of overlap and aggressive can lower cranking pressure. For instance my motor is 10:1 and with different sets of cams and overlaps I was able to swing compression anywhere from 125-190. What was ring gap and PTW?. My motor is built a lot looser then most but it is built to make a lot of power. Built loose with cams with a lot of overlap could explain it.
 
By chance does the motor have cams? cams with a lot of overlap and aggressive can lower cranking pressure. For instance my motor is 10:1 and with different sets of cams and overlaps I was able to swing compression anywhere from 125-190. What was ring gap and PTW?. My motor is built a lot looser then most but it is built to make a lot of power. Built loose with cams with a lot of overlap could explain it.
when I built my motor I noticed a variance in compression when adjust My cam gears with gsc stage 2s , what didn’t change was the variance between cylinders. When my compression lowered is was even between cylinders
 
That is true and I should have said that. My cylinders are always within a few psi of each other. Just the overall can swing a lot.
 
Not a fan of the Moto man method Matt?
I'm just not, if things aren't broke why try to re-invent the wheel? the tried and true methods for seating rings were around for many decades, rings and cylinders haven't changed, why mess with seating methods?
 
What method do you prefer? I have always broken motors in with sort of moto man method. I always check compression and leak down during break it and within very short time rings seal.
 
Sorry it took so long to reply. Head gasket multiple failures on #2. Im at fault i took the head of thinking i forgot a dowel "i didn't" i never made sure the L19 were seated all the way into the block before re-torqueing. Head was warped, i pick it up tomorrow. Cylinders look great. 8:3:1 wiseco piston eagle h beam rods. Composite hg with arp L19
 
So my head was done yesterday. Before i left to pick it up out of curiosity i asked for total height of the head. The head has been milled a total of 22 thousands. Aera service limit is 15 thou. 7 thousandths over block has also been decked unsure how much. My question is should he have measured it before milling? Im assuming the head is junk?
 
Ring gaps too large, too much PTW clearance, rings gaps not spaced 2/3rds of a turn apart are all ways to not have good compression on a new motor. A clean piston almost indicates it is getting "cleaned" by something. Was the motor decked and the head completely flat and true? Just things that could cause the problem, not sure how to cure it. Put some oil in the low cylinder and retest compression. The oil will help the rings seal if they are leaking. I would have thought it would have more pressure than 120 on a new engine, but it is within service limit.

Sorry I was referring to this post where it says 120 psi...
 
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