another oil presure question

[screamin86]

alright i know they say you only need 10lb of oil presure per 1000rpm but im just curious about the presure my 350 holds. here are the specs. gm mexico block bored 040 speed pro H580 pistons (26cc dish) stock deck height 416 heads milled 025 basic rebuild with 550 lift springs. i asume stock rods and asume crank has been turned but unsure how much 442/465 214/224 112lsa cam double roller chain summit hv pump with welded pickup for the kicked out 7qt pan. rpm intake and headers. ok I DID NOT build the bottom end i got it as a shortblock on trade from a forum member on thirdgen.org. he built it to put in a swb truck and boost it that explains the pistons and i just had a set of 305 heads done to get the cr in a useable range for a 4x4. ok at cold startup about 1000rpm ive got about 65-70lbs of oil psi which is normal and 60 or so at 700-750idle cold and if i drive at all within the first idk 3mins or so it will go as high as 90-95  . anyway once warm at cruse its at 50 and goes to about 60ish when under load. hot idle in gear is 13-15lbs and out of gear 15-20. i know everyone says thats fine and i believe it i just dont understand why its so low. it did the same when i ran a stock size pan and hv pump with stock screen. the only reason i changed the pan/pump setup was because the factory one fell off and i didnt wanna fool with it anymore and i already had the 7qt pan and pump new that was for a motor i was gona build and never finished. anyway i run valvoline 10w-30 and right now i think it actualy has a fram filter on it....i know i know bad i usualy run acdelcos or k&n filters though. as soon as i give it gas the psi will jump from idle the only time it doesnt move much is like from cruise to wot only 5-10lb diff. but to go from 13lbs to 50lbs within 1000rpm!? so again is this ok im asuming maybe its wide tollerances since it was built for boost but will it be ok in the truck? sorry fr the long post.

[screamin86]

Anyone?

[VileZambonie]

It's fine. The oil pressure is not linear with rpm. Be careful welding on the pickup tube that you don't overheat the spring.

[screamin86]

The pump that's on there now is a summit racing pump with welded/bolted pickup tube. Its actualy a melling pump I believe.

[Dr_Snooz]

Sorry, I don't have the shop manual with me to check, but isn't there a section on testing oil pressure? As long as it's within spec, I wouldn't worry about it. Ninety-95 psi sounds way too high to me, but I don't know enough about these trucks yet to say for sure. I wonder if your relief valve is working properly.

How are your startup pressures? Does it take a half hour to get up to pressure? If you are getting low idle pressures and long pressures up at startup, then I would suspect less than optimal bearing clearances in your bottom end. 

Your idle figures don't sound too low, but I would defer to the manual on that point. The engine really isn't under any kind of load at idle, so it doesn't require a whole lot of pressure. When I was having trouble with oil pressure on my Honda, I found that cheap oil filters GREATLY exacerbated the problem. I would get rid of the Fram filter ASAP myself. I usually run Wix filters. I can't speak for the K&N filters, but I won't touch their air filters. They let way too much particulate past for me to be comfortable.

[screamin86]

The 80+ presure is only if I start driving within the first 3-4mins of startup. Honestly idk why I have a fram filter on it I stapoed using them a few years ago before I even got this truck.