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SOHC compression advice please...

nsxguy7

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So I just completed a complete rebuild of my '75 SOHC. New pistons .050" over, good quality gaskets, Viton valve seals, stock cam. Head was professionally rebuilt and a reputable machine shop did the boring. Has 22psi oil pressure while cranking. I decided to compression test it just to be sure. I have 130-130-130-135 across the cylinders. Kinda disappointed when I see guys on YouTube testing junkyard motors with 175+. Anyone have any thoughts? Thanks!
 
Compression tester could be at fault giving false lower numbers. Cranking speed plays a factor. Altitude plays a factor....mile high will have lower compression then at sea level. Will probably get better once you get some break in miles but wont be a huge increase. Valve timing could be off a bit if not using adjustable cam sprocket coupled with a milled head and block. Verify valve clearances correct? Not too tight? You tube videos are just entertainment, not fact, I have never seen a sohc make 175psi...factory spec is 150 to 170, I never see them vary far from the 150 mark. If they are getting high compression then they dumped too much oil in the cylinders causing false high compression, the oil takes up the compression chamber volume causing a high compression ratio which causes false high readings. I have a perfect running 74 never had the engine apart with 9000 miles and it makes 140 to 145 psi.
 
Thanks Digger...so in your opinion, will it be ok? I should have mentioned that all I hoped to accomplish was a good running stock motor. I did some digging and found that I'm probably losing 17-18psi just from high altitude losses, which should put me around 147-148 psi at sea level. Also, I verified my readings with two different compression testers.
 
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