WW7

I have read on many forums about the use of a high volume oil pump causing problems with premature wear on both distributor gears and cam gears. It seems the added pressure from the HV oil pump pushing oil through the motor and building back pressure causes the pump to put more stress on the gears..This is why I fully expected my distributor gear to be well worn when checking it today since I now have 25,000 miles on my motor built by Pete Kane a few years ago..To my surprise the distributor gear looks brand new with no wear at all, just a few bright spots where the 2 gears engauge...After talking to a local engine builder I found out why Im not having the problems that many experience using a high volume pump...When Pete Kane built my motor he went out of his way to make sure the oil flow in my block was sufficient so as not to cause back pressure from the HV oil pump..He opened up areas where the oil would flow, and where it would return..By doing this he eliminated the back pressure most experience with a high volume pump, and also increased the amount of oil flowing through the block for a more efficent oiling system...Most that have the problem with cam and distributor gears wearing prematurly with a HV pump, use the method of putting a .030 X.030 inch slit in the bottom lobe on the distributor housing, allowing oil to drip or spray on the 2 gears, instead of relying on the splash method of gear oiling SB chevy engines use.. If your having an engine built, it would be in your best interest to have the mods below performed by the machinest in order for you to run a HV oil pump, the HV pump will get more oil flowing through the motor doing a better job of lubricating the entire engine..With the mods below and a HV oil pump, my cold start oil pressure is 62 psi, and my hot running oil pressure is around 50 psi on the highway. These are pretty normal pressures for a newer engine, but the difference is , I have much more oil going through my engine, being delivered where needed with the high volume pump , and that's a good thing...

Here are the pictures Pete shot of the areas he modified for better oil flow...

This is stock depth


This is after enlarging the oil channel allowing for much better flow to the bearings..


Hole enlarged for better flow from oil pump


Enlarged for better return flow..


He then further inlarged and smoothed the area for better return flow


Enlarging and deburring with dremel tool.

C409

..... High volume oil pumps work well with low viscosity motor oils and oil coolers ... other than that they are generally not needed in small block Chevy engines ......

DGXR

Yup, an engine's internal parts only need enough oil flow to be lubricated and cooled. More oil flow does not mean better lubrication or less wear, it means slightly better oil cooling of the internal parts and slightly better flow through an oil cooler. And more flow through a cooler is not necessarily good since the oil needs to spend some time in there to be effectively cooled.

But I like the extra attention to detail paid by your builder. Looks nice, great stuff

WW7

When Pete built my engine he did a photo documention of the entire build and posted it on the forum.. The extra machine work he did to my engine was to show what they do to race engines to get better oil flow, it's my understanding that race engines use higher viscosity oil to start with....He did specifiy that it's not really neccessary for a street engine, but If your going to run a high volume oil pump on a race engine it makes a difference.. I was just glad to be getting the machine work done for free, and having more oil running through your engine can't hurt...WW

mcm95403

HV pumps also can do a great job of sucking all of the oil out of the stock pan at high RPM, which makes for all sorts of interesting lumps of metal for your desk.

cv67

I used one in mine only because it can turn some rpm and helps cool the springs a touch or id like to think anyway

Have gotten a little wear probably due to the billet cam gear that found its way on there that wasnt supposed to be

I dont run more than 10/30 syn and wait til the oil (not just coolant) is good and hotbefore I stand on it.

x2 on a stock pump doing the job 90% of the time

Change to a Z/28 spring if higher pressure makes you feel better

SBC have a very good oiling system

383vett

Hard to see here, but my motor has the lifter valley ground smooth to help oil return.

mcm95403

C'mon Willie - you just wanted to show off the solid roller cam

gerardvg

I have a high volume oil pump in my 383, have never seen a drop in oil pressure at high rpm or acceleration. I guess the oil must be finding its way back to the sump then.

My previous car had a high volume oil pump,the 351 ford cleveland engine i had that loved spinning to 8,500 rpm but that did have a larger sump.

PcolaPaul

A small block has a good oiling system stock. Unless you are running a loose engine, with big bearing and rod side clearances a stock pump is fine.
Small blocks do like to oil heavy on the top end, adding oil restictors in the galley plugs will keep the oil in the pan, where it belongs at the oil pump pickup.
Adding a windage tray for high RPM engines is a good idea. It offers a small HP improvement, but keeps the oil from being "Foamed" from the crank throws causing turbulence in the oil pan.
10 psi for every 1000 rpms is good. You don't need 60 or 80 psi hot oil pressure unless you are turning major rpms. Oil starvation usually causes engine failures, not lack of pressure.

81c3

Any small block Ive ever built, I always chamfered the oil drain back holes in the top end of the block. Also, on the heads (iron old skool) I cleaned the edges of all the drain back bores. Its a good practice for any engine IMHO.

383vett

Hydraulic

Tommycourt

Sounds like you had one heck of a good mechanic to do all of that on his own instead of letting you learn the hard way. He should be commended and you should feel lucky to have that kind of machinist!!
Tommy

jake corvette

http://speedtalk.com/forum/viewtopic.php?f=1&t=6176

Here is an interesting thread on another site that talks about the effects of high volume pumps. Some pretty good information - - both pro and con.

Like any group of scientists, there is not a universal consensus

Enjoy -

Jake -

barrypaul2005

I was searching past info on oil pressure and noted back in May 2008, WW stated:

and was curious to see that WW did a ZZ4 short block replacement a couple years back, what prompted the replacement engine and do you (WW) still stand by your original statement about oil pressure above, or do you consider it too low now?

I have about 18 psi hot idle and 35 cruising with a max of 39 after a ZZ4 short block swap ('89 coup auto ) using standard oil pump.

WW7

I did replace my stock L98 about 4 years ago, but not with a ZZ4 engine.. I had Pete Kane build me a 383 stroker motor that puts out around 400 hp , I replaced the motor to get "More Power"",no other reason. ...The lower oil pressure I had was with the stock L98 with 132,000 miles on it and I never had any oil pressure related problems with that engine..As a matter of fact a friend of mine is now running that engine in his pickup truck with no problems, and it still has the same oil pressure....I would expect a new ZZ4 engine to be running more pressure then I had since tolerences would be much tighter..With my newer 383 motor I have 62 pounds at startup and about 50-52 pounds at running temperture at 45 mph and (55 pounds pressure at 55-60 mph)...For a new motor your pressures are a little low but shouldn't cause any problems.. Your motor may have been built a little on the loose side which would give lower pressures, if this is the case a HV oil pump may get your pressures up where you want them to be. Have you checked to make sure your gauge is reading properly?. You may want to use a mechanical gauge to check that your pressures are really low and not a bad oil sending unit.. ... One other thing that can cause low oil pressure on a new engine, is if the builder forgot to put in the metel plug that goes in the block under the oil pump..This metel plug is very important and if not installed can cause low oil pressures because of oil bypass...You may want to check on this plug ........WW

Below is the plug Im refering to , if it's not installed your oil pressures can be half of what they should be, and it's not unheard of for builders to forget this plug......

mtwoolford

At last, someone who gets it right

barrypaul2005

WW - thanks so much for the follow up. That is great news.

I got the ZZ4 from GM directly ($2300) and installed it myself. That's interesting that's there a plug under the oil pump. Who'd thunk to double check this before installing. Something to keep in mind though if I ever have to go under there. I'll check my old engine when for reference.

I've got a mechanical gauge and plan to test things out after break in. I did replace the oil sender a few months ago (before the engine swap) and the new sender actually read about 5 psi lower.

It's strange that my old engine had about the same oil pressure at cold start up as the new ZZ4 - 39 psi - I never remember ever seeing more than that.