low oil pressure wot
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i have a forged 347 1000 miles on engine, since day one the hot idle oil pressure has been like 26psi after the first like 300miles it went to 19-21psi @183 temp. for the past 700+ miles. cruise is like 34psi @ 1500rpm but wot will go to 28psi and build to 34psi by 6000rpm or sometimes it will stay at like 32 and never move. it has a melling pump, its a h/c/i car like 430rwhp no unushall noises. i tried different filters and oil currently running 10w40 i cut the last oil filter open and it was clean. is this maybe worn mains or cam bearing installed wrong, ireused the stock main bolts, its stock crank, lunati rods ross pistons, i cant remember i think i had .002 on the rods. i put the pick up on while on a engine stand so i dont think i messed that up. this is in a c5 so its kind of a pain to just check it out. i might try a new pump and o-ring any suggestions?
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Oil pressure dropswhen wot? That could be berings thats a sighn. Then again a tight spec motor will show higher oil psi as well as temp. A loose motor will show the oppsite and burn alittle more oil. Have you tried a different sending unit and a manual guage ? Also what type of oil? Synthetics flow better when warm and will show a lower pressuer. Dino sludge will show a higher psi hot or cold because the viscosity is different.
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I'm thinking the O-ring is prob pinched. This is the most common problem with newly built engines. People complain of really low oil pressure, and it seems 9 times out of 10 it's the o-ring. I would find the problem before doing anymore WOT pulls, bc your bearings are not liking that low of oil pressure.
Maybe it's the melling pump though, I really don't know much about them. I use the ported and shimmed LS6 pump. It works great for me, as I have around 75-80psi of oil pressure at WOT and 60 or more at idle.
When you go to install your o-ring always, ALWAYS lube it first. I used some grease on mine to make sure it would slide right into place, and no problems here. You can't just slide it in their dry and expect it to be just fine.
Anyways enough rambling on, just check the o-ring before you F' up your new engine.
Maybe it's the melling pump though, I really don't know much about them. I use the ported and shimmed LS6 pump. It works great for me, as I have around 75-80psi of oil pressure at WOT and 60 or more at idle.
When you go to install your o-ring always, ALWAYS lube it first. I used some grease on mine to make sure it would slide right into place, and no problems here. You can't just slide it in their dry and expect it to be just fine.
Anyways enough rambling on, just check the o-ring before you F' up your new engine.
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WHIPPLE Superchargers, Procharger, Magnuson, Powerbond Sale, HPTuners packages!, Trickflow, AFR, PRC, CHE Trunion upgrade, $100 7.400" pushrod set, Custom Cam of your choice