For a standard engine?
Any to avoid, or any that really stand above the rest?
No point in going overkill, but i'm looking eventually at a rebuild for peace of mind.

 

Melling M55

 

Mr Gasket #26 pressure spring added to the above. Pumped oil through my LG4 just fine.

 

you'll have a hard time finding anyone saying anything other than a m55 and the #26 spring, even if you did a search and looked for it

 

I know alot of people will disagree, but I always use the M55HV that comes from Mellings with the Pink spring already installed. It is a few bucks more, but works well in my truck engine builds. Oil pressure at idle and low spees is almost always 60 or above even when hot. Even on a 100* day here pulling a load, they still typically idle with 45 psi at 600 rpm.

The counter arguments will be that it will suck a pan dry (truck pans are 6 quarts so I don't think so in my case), they take a little more HP to drive which is true, and are probably a little overkill.

 

It is true that it can suck a pan dry, but if its a truck motor, it won't be revving near fast enough to do it. It will also use up more power, but I doubt it would be a notceable amount.

I'd still go for the M55 though.

 

I've run my 355 and 312 to 6,300 rpm for brief periods and never seen any pressure fluctuations that would result from running the pan dry. When I say brief when on the wideband under load on the mustang dyno we twisted it to 6300 at 200 rpm sec acceleration. Never had an issue with oil pressure. Now on a 7,000+ rpm race engine the situation might be different. I really don't see how you can suck a pan dry still. You have a certain amount of oil that is going to leave your bearings, lifters, etc. Its not really a function of RPM. Provided the pump will pump more at RPM, most of it ends up going out the Bypass on the side. With good oil drainback, a good scraper and windage tray, the oil will go back in the pan.

 

Thanks all, as usual for the good advice, seems Mellings the winner.

 

I agree with the M55 & Mr Gasket #26. I'd add, use the Melling IS-55E drive shaft, which has a metal collar holding it on the pump instead of plastic; and don't forget to put the shaft on the pump BEFORE installing the pump, and the oil pan, and putting the motor back in the car.

I would strongly advise against the M55HV. It is unnecessary, and is simply a good way to satisfy people who have these hallucinations about needing them. Unless you drive the world's fastest van and publish your claims about its performance in The Journal Of Irreproducible Results, you don't need one of those.

 

Smokey first started by adapting a Big Block Pump on a Small Block. Smokie Yunick used a very simlar pump in ALL his small blocks back when. He built many performance engines so he knew his stuff and had a reason for using it. No reason not to have 70 psi of oil pressure at 1,200 rpm. It takes the M55 about 2,500 rpm to reach that pressure. With the M55 in a severe duty application you can beat the bearings out at low-rpm easier(think blower or nitrous). The M55HV works well with turbos and centrifical blowers that need oil from the engine. And the rest of your post bashing me.

Other than that good advice on the steel collared pump shaft, it is required on the 55HV.

My opinon still stands, if you are going to work the engine hard in the lower rpms for very long use the HV pump. If you spin them to the moon and care about the last FRACTION of a HP use the standard. For street duty its hard to beat the HV.

 

Ya know, actually I was....

Although, the original poster didn't say Word One about nitrous. In fact, unless he's edited his post lately, he said something about "for a standard engine". Thanks for bringing that up though, it's good to know that you keep nitrous right at the top of your mind, in addition to reminding me of it.

Yes, we all know about the big block pump; those of use that have been building motors for a while that is. That's what the M77HV is, in case you don't have one of those on your van yet: it's a stock BB pump with a special screen to fit a SB pan. But those of us who aren't running nitrous , or who haven't modified our bearings from stock (like full-grooved mains and cross-drilled crank journals) don't really need any such thing.

I don't recall bashing anybody. Who me, bash? Who did I bash? How did I do this bashing? Did something I say make someone feel uncomfortable? Aww, shucks, I'm terribly sorry.

 

From everything I have seen... You cant go wrong with melling. Just make sure to get the pickup and a new screen and everything you need. Just put it all new down there and you shouldnt have to worry about it for years and years

 

Actually, most of the reason for using a big block pump in a small block, is because the big block pump is much smoother in operation, and reduces spark scatter on the old points ignitions.

 

That was one reason, and the gears are taller giving more volume.

The original poster didn't mention NITROUS but I did as an extreme case.

I don't really care about being put in TJOIR.

My stock 305 crank was cross drilled so go figure.
3941188....350(apparently some 305s).......forged..medium journal...3.48" stroke

 

i have personally pulled the pan dry in a high rpm/hard cornering situation on several occasions.this was in a '67 ss/rs that had 5 leaf rear springs and big block front springs.it had a moderate 350 that that had the oil passages and return holes cleaned up.
this was with a melling hv pump.
the best way to spot oil pressure sensitivity is on a tight freeway on ramp!gradually accelerate into the ramp as you keep an eye on the oil pressure gauge,sooner or later you'll either spin out or you'll notice a dip on the oil pressure gauge.
if your gauge dips at high rpm rolling into a corner,you need a lower volume oil pump,(as long as the pressure is ok in a straight line!).
if it dips at a lower rpm(3,000 or less),you need a new oil pump or a better oil pan.
if you spin out,,,,,,work on the suspension!
Eric B

 

I have been looking at the melling 10555 pump with the gear shafts extending into the lower housing, and a bolt on oil pump pickup to decrease the chance of loosing the pickup. Seems like a good choice to me. More money but, still a good deal.

 

Does the pickup fall off often?

[he asked worriedly]

 

It has been known to happen.

 

use a stock pump with a stiffer spring
the larger pumps will eat up an extra 10 hp
more PSI less hp loss. cheaper too!

 

If you can prime an engine with a 1/4" drill there is no way it will take 10 HP to turn the pump. My understanding is that Melling uses a 1 HP motor to turn their oil pumps up to about 125 psi. ( I read this somewher in all of my books ) I can surely locate it again if need be.

 

a larger pump= more volume which means the pump draws more oil, which then causes the engine to loss hp. The engine is going to struggle because its picking up more oil.

 

I still want to see the dyno slip showing a 10 hp loss from switching to the HV pump.

I use a HV pump. Does that mean I can gain 10 hp from switching to a normal pump with #26 pressure spring?

 

Yeah you are still talking about a fraction of a HP, not 10. The 10# You can run a log spliter which pumps about the same GPM as the HV pump at like 1,000 PSI on a 5 HP Briggs and stratton.

As soon as you hit the 70 PSI spring, the bypass lets the extra oil back to the pan but the power required to pump the oil only goes up slightly. Your talking maybe a 1/4 of a HP more. My battery powered el cheapo drill will put 70 PSI of oil pressure on the gauge while I am priming engines.

I could see severe cornering loads affecting the oil pickup, but it is mainly from poor baffeling.

 

Nothing to argue over...but definetly something to try out on a dyno sometime.

 

Anyone ever hear of high volume and or high pressure oil pumps causing lifter pump up; specifically hydraulic roller?

 

Finally something relevant in the discussion. I promised myself I would sit quietly on the sidelines about this... but, awe shoot,
About pressure:
Take apart a hydraulic lifter and read up about how it works. If you spin the smallblock up past 6200 much with hydraulic lifters you don't want 60-70 psi of oil pressure. The lifters will pump up and much heavier valve springs will be necessary to keep the valves on the seat. Heavier springs increases cam lobe wear dramatically. This is why race engines have solid lifters. More oil pressure doesn't mean an engine will take more punishment either. Race engines would run 150 psi if that were the case. They don't. The pressure of the oil is not what keeps the rotating assembly parts from touching each other. It does have everything to do with oil consumption past the rings. The cylinders are lubricated by throwoff from the crank. Increasing the oil pressure increases the throwoff and overloads the oil rings. This causes detonation, which is really bad.
About volume: If a stock pump completely supplies the block and
starts moving oil out of the relief valve at 1500 rpm, putting in a larger volume pump only increases the amount of oil that is blown past the relief valve. Do some quick math. 6000 rpm=amount of oil the block uses, and 3 times as much more blown past the relief valve, WITH JUST THE STOCK PUMP! Now change it to a high volume pump that pumps 25% more. At 6000 rpm 4 times as much oil as the block uses is going past the relief valve. This just foams the oil and sends vibrations up the distributor shaft creating spark chatter. Now add in the fact that the guy has been told that high performance engines should use 20W50 RACING OIL! Now you can see where you get broken oil pump shafts, stripped distributor gears, and blown oil filters.
In short: use a high volume oil pump if you run big clearances and must to have pressure at low speed. Use thicker oil than 10W30 if the high volume pump still isn't enough or consumption past the rings is excessive. 40 psi of pressure at 2000 rpm is plenty for earlier non-LSx engines.
<exiting soapbox and donning asbestos underware>

 

Well, the question was generic when I asked, but I'm dealing with a BBC.

As I understand it, BBC's with hydraulic roller cams have issues with valvetrain wt.

When my truck was in the shop having the exhaust installed, I thought it would be a good time to install my Moroso pan. Of course, the pan required a specific oil pickup. The shop took it upon themselves to install a high volume pump.

Just curious if the pump could cause loss of valvetrain control.

We're talking about a mild hydraulic cam that should never see the high side of 5500.

Guess a simple oil pump change would confirm or deny my suspicions.

 

If the max oil pressure before and after the change are close to the same it won't be a factor. If the new pump makes 10 psi or more than the old one it could be. If the engine runs differently it's more likely that the battery was disconnected during the exhaust work and the computer is having to "re-learn" the engine.

 

At least 10 psi more.

Good theory on the battery thing, but I run open loop; Autoprom, etc.