Chris Edwards

I'm doing a cam swap and I wanted to install a new oil pump, even though the motor only has 67k on it... I will also be installing a large Setrab EOC with -12AN lines and I'm wondering if a ported oil pump would be a good idea? I'm thinking High Volume is not a good idea?

0Randy@DRM

You do not 100 percent need to do anything special. But adding a shim to a stock pump adds to the pressure output. Porting doesn't really make huge gains in pressure but will add to the volume a bit.

Is your current oil pressure good?

Randy

Chris Edwards

Current oil pressure is 27-29 at hot idle, 60+ at WOT. Since I have the whole motor torn down for the cam swap, I figured at the very least I should put a new (unmodified) oil pump in to replace the original. But I also was wondering, since I'm adding a few quarts to the system, if I should shim or port the new pump?

Chris Edwards

Any other input guys?

J.R.

Agree with Randy.

Unless you drill lifter trays and or use restricted pushrods you will just end up with more oil pooled in the heads with a high volume/high pressure pump.

I would use a new LS6 oil pump. Try to make sure it is appropriately centered before tightening bolts.

Supercharged111

Here's my take: if you port the pump for additional volume, and said volume isn't necessary to crack the regulator open then it won't flow more oil through the engine rather it'll just push more out the regulator. The regulator determines pressure, which is related to flow (pressure at the pump, not after the cooler). If you shim the pump, the only way for you to see that added pressure is if more oil is cramming its way through the bearings. Will it flow more as stock? Sure, but again the added flow will increase pressure but the regulator will regulate that so it may be a moot point. I have seen a chart indicating flow cavitation somewhere north of 6,000 RPM and I'd LOVE to see some empirical data that shows changes in flow/cavitation with a ported vs. non LS6 pump.

RapidC84B

I've had good experience with the LS4 high volume pump with the 42 psi relief. In my current motor I run restricted flow pushrods and drilled lifter trays but I didn't in my old motor. No isssues. Car never drops below 50 psi on track even in the summer heat. I run Amsoil 10w40 and a K&N racing filter.

Chris Edwards

What will drilling my lifter trays do?

RapidC84B

Increases oil return to the pan.

Chris Edwards

Are those just 1/4" holes? Does drilling the lifter trays affect lifter life or noise in any way? I will do that if it's a recommended modification. Let me know what other tricks you guys have that I should perform to the oiling system while I have it apart.

So far I have:
New LS7 lifters
New LS2 trays (plan to drill them)
New LS6 oil pump (unported, unshimmed)

0Randy@DRM

No known problems with drilling the buckets. There has been some reported issues with batch number 10 on the lifter buckets. To the point if you have number 10's I would replace with new ones. Rare, but why not.

Randy

Supercharged111

There are so many success stories out there about all our different setups, are there really any oil failure stories out there on an LS6 after an oil cooler install? It's almost like you can't go wrong with these no matter how much or how little money is spent on extras.

C66 Racing

Well... two of the guys racing LS6s out west have lost their engines already this year. Seems like both were seized bearings as from pictures it looks like rods came out the side of the block. So oil related failures will continue to be something I lose sleep over at the track.

redtopz

I'm one of them and mine was not an oiling issue. The other was my buddy who had 2-3 years racing on that engine with a stock oil pan. Not too bad, but I agree a good oiling system is worth it's weight in gold.

OP, your current oil pressure sounds a little on the low side. I think it's a good idea to install a new oil pump whether you port/shim it or not. I wouldn't worry about the oil cooler needing more pressure. Just make sure you get a large cooler that can handle all the oil flow (sounds like you are).

C66 Racing

It was a seized bearing, correct (rod rotated out of the engine - bottom in your case I think)? Assuming I'm correct, while I agree it really isn't directly an oiling issue (like loss of oil pressure), I would say it is oil related as oil is the film preventing metal to metal contact between your rod and the crank. Either way, seized bearings really scare me.

P.S. Really appreciate you posting all your info on your current NASA ST2 to SCCA T1 conversion. I'm going the other way (SCCA T2 to NASA ST2), but have my eye on going back someday (if the SCCA stops changing the rules every year which I can't afford to chase). My first race in NASA Apr 26-27 at Summit Point.

redtopz

No it wasn't anything internal in the engine. Read my latest post in that thread and you'll see what it was . Welcome to ST2! Most of us out here are running ST2 and T1 this year with Runoffs at Laguna. You should think about it as they are exactly the same car. I'm even running the same restrictor for T1 and ST2 this year. The only difference is I'll pull out about 100 lbs of ballast for ST2. Good luck in your first race!

Chris Edwards

Well guys, I'm still debating my oil pump decision.

I've narrowed it down to:

GM LS4 pump ("newer" 42psi relief version)
Melling 10296 (which spring to install?)
Melling xxxx ? (some other Mellings, God there are so many to choose from)
GM LS6 unshimmed
GM LS6 shimmed

Would love to have someone make a decision for me lol.

fruitsalad

You would want the Melling 10295 standard volume as opposed to the 10296 high volume.
A ported LS6 is a good choice as it likely would not need to be pulled apart before install to clean out casting flash, which is necessary with any brand new Melling.

Chris Edwards

Thanks for your post. Can you explain your thoughts on why this would be the ideal unit?

Chris Edwards

I emailed Doug at Precision Oil Pumps (www.precisionoilpumps.com) and got the following response:

Thanks for your interest in our LS Pumps. The larger volume pumps are a must for the external plumbing you have. Dont be scared it has been done more than you think. The only issue with the large volume pumps are the timing chain rubbing. It may need spaced and some grinding. Keep this extra work in mind. The 10296 is minimum choice or 10355
Thanks, Doug
Precision Oil Pumps
(559)325-3553