96lt4c4

iTrader: (5)

Do I need one? I am building a new stroker, rod and main bearing clearance is .0025. I bought a new standard volume high pressure Melling Select pump but now I am wondering if I need the high volume, high pressure.

If I run the High Volume do I need to change pans to run more oil?

pauls99z28

iTrader: (32)

here is info from moroso's description
This should explain what your asking.
I personally have a Melling high volume but moroso explains it better...lol.

"Moroso has now released its own version of a high volume LS1 Oil Pump. Research has proven that a smooth, adequate flow of oil contributes more to engine life than erratic flow, regardless of total pressure. Pump housings feature special feeder grooves that fill cavitation areas, and enlarged pressure relief ports for smooth flow, improved performance and more oil where you need it."

96lt4c4

iTrader: (5)

Sort of helps, but still does not answer the question to how much oil I need in the pan. I know on the SBC you did not run a high volume pump unless you had a higher capacity pan or you could suck it dry.

JakeFusion

iTrader: (7)

That's what is said for LS1s as well, but some builders will tell you only to run HV pumps. I think I've maybe only seen a couple suck a pan dry and that was during road racing. Which can happen without the proper pan anyway.

I run HV - just run 6qts and the truck filter for extra capacity and you should be fine. I'd definitely do it with looser bearing clearances. The two truck filters I use are the Wix 51522 or K&N 2006.

Gray86hatch

iTrader: (83)

If that is a alum block the mains are a little big. I like to keep them at .002 with 200 degrees in the engine they will grow almost .001

Tim

96lt4c4

iTrader: (5)

Yes its an LS2

That's kind of what I thought. Funny thing is my machine shop told me that the mains may be too tight. Almost all came out to .0025. I checked by micing the crank then zeroing my dial bore gauge inside the mic. Then sticking the dial bore gauge in each cap with the bearing in it torqued down.

I do like to do a little Autocross, you think I can suck the pan dry? Should I get a better pan just to be safe?

Gray86hatch

iTrader: (83)

I had mine at. 0027 and had issues. .002 to .0022 is the max I would go for.

Alot of shops don't understand what happens with heat to the mains on these engines

Your rods are fine

96lt4c4

iTrader: (5)

What kind of problems did you have? I have king main bearings, If I wanted to tighten the mains up some what should I buy?

JakeFusion

iTrader: (7)

Don't worry with a new pan - the pan that GM provides is part of the structural rigidity of the block. Most aftermarket pans don't provide that.

Just get a new baffle from Improved Racing. It's cheaper too.

http://www.improvedracing.com/oil-pa...ffle-p-30.html

Gray86hatch

iTrader: (83)

Those baffles don't fix the pan or the lack of capacity

Oil pressure at hot idle was almost not there. Re-hone the mains to tighten them up and use the same bearings. I like to keep the main bore dia small to keep the crush on the bearing.

Tim

96lt4c4

iTrader: (5)

Talked to Melling tech support today, George the guy that makes the Melling youtube videos, he said with the extra clearance I have that I need to run the HV pump, 10296, so I have to send mine back to Summit, I have the 10295.

He also said the old SBC HV pumps had 25% extra volume which could cause problems with the stock 5 quart oil capacity. The LS HV pump only has 18% extra volume which will be fine. I may go ahead and run the bigger filter as stated above. The extra oil cant hurt anything.

Gray86hatch

iTrader: (83)

I would still fix the mains. Even with the bigger pump the idle pressure will be below 20 with 200the degree oil temp

MillsMotorvation

Well I suck my pan dry coming from the track one night running a import on top end, my car would get a 100 oil psi hot on a pass thats to much. Got the standard one in my neww engine 408. Has 28-30 psi hot, and 40-60 psi WOT. Oh my car has a turbo, and oil cooler. Good luck.

96lt4c4

iTrader: (5)

The 10296 comes with a lower pressure spring. The high pressure is installed. I read a very informative post from Jason at lingenfelter that said too high a pressure is what sucks the pan dry. So if I put it in and worse case my pressure is through the roof I can change the spring. May change it before I install it anyway.

96lt4c4

iTrader: (5)

Are you sure you didn't have something else going on? Not doubting what your saying but I have talked to guys that have ran the same main clearance I am with the ported LS6 pump and they were running 35 psi at hot idle. The main guy I am talking about has built several LS engines. The current engine he is working on is a twin turbo LS2 and he is not thinking twice about running the mains at .003.

96lt4c4

iTrader: (5)

What pump you running? Main and rod bearing clearance?

TexasGMC08

18% is not much for a hv oil pump...run a oil pump that was used on a dod engine...

96lt4c4

iTrader: (5)

LOL...You must not have watched the video, George says, " That is not Recommended"....

TexasGMC08

ha i just watched it!!! Did he give a reason???? No he did not but how much did the dod put out??? 35%!!! And it's not a hv!!!! Nice sell's pitch george!!!! Go with the dod pump!!!

awd-rwd racer

iTrader: (16)

b/c the DOD engines use 8+ quarts of oil and use the oil pressure to turn the lifters on and off. so do not use a DOD oil pump unless your car has DOD