gofasthotrods

I posted this in my build thread as well but figured I would ask here as well:

5.3L with LS1 Heads, single turbo with 4AN feed and 10AN return. Remote oil filter (due to the front sump oil pan) and oil cooler.

I need some advice on the oil system for my build. I wanted to add an oil cooler to this set up but I'm not sure the stock oil pump will keep up. I have 12AN hose for the cooler and remote filter. I think I would end up with about 15-18ft of hose and at least (4) 90 degree fittings. Anyone have any suggestions or real world experience on oil pump needs for this build (single turbo, remote oil filter and oil cooler)?

Kjduvall

high pressure std volume would most likely work just fine. im sure others will chime in with thoughts as well.

grinder11

iTrader: (1)

I'd go with a Melling hi volume-standard pressure. I've had one in my engine for over 17 years. Stock pressure is fine. I think the model# is 10295. Comes with std pressure relief spring, and hi pressure spring. Again, std spring is fine.

dixiebandit69

Or you could just shim the spring in a standard volume pump.

91 Z28

iTrader: (3)

Yep that's all I did with a stock oil pump.

grinder11

iTrader: (1)

Shimming the spring in a standard pump does nothing for volume. Sure, it'll increase volume (slightly) at rpm above the point the relief valve starts opening without the shim. But high g-forces at, say 3,000rpm in a 90° corner, the Hi volume pump holds all the cards. They're made for a reason. If simply shimming the relief spring worked as well as a hi volume pump, nobody would buy hi volume pumps......

91 Z28

iTrader: (3)

I'm running a remote filter and single turbo in my 3rd gen Camaro using 10an lines from engine to filter then from oil block to turbo is 4an using a shimmed stock oil pump with zero issues.

If you've got loose bearing clearances or doing high G 90* turns like buddy is saying then yea go high volume otherwise your standard pump will do you just fine

grinder11

iTrader: (1)

I agree with you. 10A/N is what I run, too. Most coolers I've researched with 37° (A/N) hookups are #10. Also, another thought (intended for OP) on oil pressure. There are WAY too many people running ridiculous oil pressures on many engines. Generally speaking, stock pressures are fine. The more pressure you run, the more power it takes to spin the pump. Sure, it's not 5 or 10hp, but at high rpm, I think many would be surprised how much power it takes to supply 75psi at 6,500-7,000 rpm. Every little bit helps. I'm also of the opinion that the higher the oil pressure, there will be a small amount of heat added to the oil. Again, not much. But why run 75-80psi when:
A: it's not necessary
B: it takes more power
C: it may heat the oil a couple of degrees
D: you could start oil aeration.
I offer no proof of adding heat with more pressure, so I may be wrong on that front. However, I AM correct on oil aeration of the oil at high pressures. At what pressure, I don't know. Maybe Poly will chime in. I do believe it occurs under 100psi in LS engines. I dont have the exact number. However, according to Dart engines, the stock LS engines have way too much oil circulating at redline. IIRC, they said at approx. 6,200rpm, there is approximately 18 GALLONS (!) per minute flying around inside an LS, way more than the Gen1 SBC!!! If you go to a high pressure pump, you will actually increase volume slightly. Pressure is determined by clearances in the engine. Bearings lifters, etc. A Hi volume pump which has a stock relief pressure spring will actually flow less oil (not much) than a shimmed relief spring pump. Where the Hi volume is beneficial is when, and if, the pump cavitates. It will recover pressure quicker than a stock pump, shimmed or not. IIRC, the Melling 10295 is about 3/16"-1/4" wider than the std pump. I've known guys at the strip who run 30-35psi at high rpm, and idle at 15lbs. Not saying I'd do it. But their motors never had any oil related failures. I know this is long winded, but honestly, 50-60psi at max rpm is great, with 20-25psi at idle in the same motor. My 2 cents.......

91 Z28

iTrader: (3)

Nicely said. I agree with not needing insane amounts of oil pressure I'd also have to agree with too much pressure causing a slight rise in oil temperature, how much tho is anybody's guess but I'd think a cooler would take care of that issue entirely especially if it's got an efficient fan.

I shimmed my stock pump with a little 10mm nut and I data logged about 25-30 hot idle, 40ish light throttle cruise and 60-65 WOT

grinder11

iTrader: (1)

PERFECT!! THIS is exactly what most should be targeting. Shimming doesnt do much, if anything, at idle. I have piston oil squirters in my LS7 block, the main reason for the 10296 HV pump. I am running the stock oil pressure relief spring. When my oil temps hit 200-210, I'm around 25psi@850-900rpm idle, 40-45 cruising, and 65psi@redline (7,000rpm)

SoCalDave

I understand the no shim in the oil pump thinking. However it seems to work for my LS1 as I swapped the cam and installed a new Melling M295 with a couple shims under the pressure relief spring which brought up my hot oil pressure from 20psi to 25 psi. That was without porting the internals of the new oil pump.

91 Z28

iTrader: (3)

Yea exactly my line of thinking is that if it works it isn't stupid