High oil pressure?
 

Found out that the oil pressure with 20/50 wt when rev engine goes to more then 90 pounds also heavy spring in oil pump?:confused: Is oil to heavy? Thanks

Re: High oil pressure?
 

Thanks James!!!

Re: High oil pressure?
 

Why are you using that heavy oil? Try 10W-30. You don't have a top fuler do you? Use synthetic racing oil.

Re: High oil pressure?
 

Way too much oil unless that's a Cleveland. Even 5W 30 synthetic is plenty.

Re: High oil pressure?
 

No Top Fuler, Would not have one of those oil down track junk!!!! Its a bracket car 400 small block 10.20 at 131.89 at wt 3160. Thanks Guys, You all are the Best!!! What wt of oil do you all like?

Re: High oil pressure?
 

I'm guessing you have HV pump with about .0015-.002 bearing clearanceGo to 10-30 or 20 may lower when warm. 90 lbs won't hurt anything besides taking a little power or worst case wear dist. gear. If oil does'nt drop psi enough to suit you change spring or pump.
I've been using 10W30 and 20wt for a long time.
Mike Taylor 3601

Re: High oil pressure?
 

I don't know why they even make high volume oil pumps for the sbc. Absolutely no need for them. But, if you make them somebody will buy them.

Re: High oil pressure?
 

Ed:
I know for a fact that Fadely & Edwards ran HV + HP Fadely had a supply of the old trans-am oil pump springs with a .125 shim = 85 to 90 hot and Pennzoil 20-50, I had the deep rotor (from 534 Ford Truck engine) covers machined at one of the Ford Machine shops. The 351-Cs need alot of pressure.

Re: High oil pressure?
 

But, those were Fords. And sbc = Small Block Chevy, which has a great oiling system, unlike the early Fords. Myself, and many others building small block Chevys use the STD volume pump, modified for LESS volume. I also limit mine to 40 psi @ 8500 RPM. Bearings always look like new. Just replace them when I start to feel guilty about running them so long. If you ever build a sbc, call Larry Stewart Sr about buying an oil pump.

Re: High oil pressure?
 

I'm going out to the shop and put in the 5/20 wt and see if that does the FIX.

Re: High oil pressure?
 

I would like to add my $.02 worth and I dont want to step on any toes. Oil pressure within a engine is determined by resistance that is "seen" within the engine,etc tight or loose clearance, small holes versus large holes, programmed bleed off built within the engine. The relief spring only sets the pressure that it opens to bypass the pump. Theoretically you would want your bypass to open ever so slightly in operation so that it is not cycling too often. Yes you are correct on oil viscosity being a determining factor also. Thicker oil will have more resistance, therefore more oil pressure. There has always been a misconception that a high volume oil pump is a no no. But that is not necessarily true as resistance to flow(clearances will determine how much oil will go thru the engine). I have heard many people say that it will empty a oil pan. The only way that can happen is you already have too much clearance and the pump is trying to meet the demand. Many smart engine builders use HV pumps so as to have enough volume later in life of the engine as clearances begin to get larger from wear. Of course race engines are normally built with a pump that just meets its demand as the engine will never "wear out". Synthetics has change many facets of oiling as we can do things now that we could not do even 10 years ago. We can now run closer to the edge than we ever could with mineral base oils.
Hope I did not step on any toes. Sorry for the long dissertation
Charlie

Re: High oil pressure?
 

I put in 5/20 wt oil and let engine warm up to 150 and pressure was 60 and over 6000 stop at 75. Thanks Guys for all the HELP!!!!:):cool:

Re: High oil pressure?
 

The high vol. pump pan dry myth,I found where that came from @ PRI show one time Melling had a bunch of bulletins,one addressed that it came from old Y block fords292,312 they did'nt have good drainback and not much restriction to top so it was possible to pump pan dry ,but stated most modern engines that was'nt possible.
Mike Taylor 3601

Re: High oil pressure?
 

There where some SBC out there that had wrong crank drillings and would shut off oil at Habove 7500 rpms you would show pressure but could not feed rods

Re: High oil pressure?
 

"Many smart engine builders use HV pumps so as to have enough volume later in life of the engine as clearances begin to get larger from wear."

I would have to debate the "smart" part of that statement. SBCs typically run well over 200,000 miles with no oiling issues, way more than a race engine will ever see. The factory pump has plenty of reserve capacity to compensate for wear. Pumping the pan dry? There are other problems if that happens. What actually happens is the pump bypass stays open, peeing un-needed oil right back into the pan. Heats up the oil, wears the dist & cam gears, and wears the thrust areas on the back of the cam sprocket and front of the block, wastes power. I've seen those areas really chewed up over high volume pumps in local roundy-round engines. Absolutely no need for them.

Raph, I've been doing this for fifty years now, I have never seen a crank drilled like that. But, old as I am I haven't seen everything yet. :-)
Don't think a bigger pump would be the correct fix for that.

Re: High oil pressure?
 

Nope it has to do with the angle of drilling vs Stroke> It will just flat shut the oil off, the SBC cranks I am talking about were made by BRC when they were doing cranks in TNN. Had a small block Ford that Crower did from a Ford Forging same way it was something to do with the cross drilling and if you put a plug in the one side it would crutch it but not totaly fix it thing go wrong about 7500 to 8000 if you stayed below that RPM they would last, but above it would shut oil off and spin bearings. There is a article some where on the Internet but cna not Find it FJ Smith might come in on this, I thinkd he had a couple of these cranks.

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Thankfully I never used one of those. lol

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Takes a while for the newbies to catch on Ed. I was doing the same thing to my pumps back in the late 70's and 80's. And we're not talking about changing the bypass spring.

Re: High oil pressure?
 

Wish I could think of the guy's name that got me thinking correctly about sbc's oil pumps. He was a Modified & Comp engine builder from New Mexico in the '70s. Wish I could think of his name now. (I’m old) Had the pick up tube fall out of the oil pump in my ’56 Chevy at Albuquerque NM. Too much blowing sand & dirt to pull the pan there! I just loaded up. He was asking what happened, and told me I should be pulling the spring and braze the pick up in place, then ask how much oil pressure I had? I proudly announced “65 psi!” He said, “And a high volume pump?” I said “Yes!” He then screwed my head on straight about pumps and pressure. I have an old rear main cap, tapped for a fitting, flexible hose and oil pressure gauge. I bolt the pump to it, drop in the parts washer and spin it up with a ½” drill. What I see there, I see in the car. Been doing it this way since that day. Before synthetic oil too. <G>

Re: High oil pressure?
 

McClintock?

Re: High oil pressure?
 

Sounds right.

Re: High oil pressure?
 

ran a Street Roadster

Re: High oil pressure?
 

Yep. That's him.

Re: High oil pressure?
 

Mike Keown got me up to speed on the pumps. I was getting the good synthetic from Alaska and overseas before it was available here. I worked at one of the largest Chevrolet Dealers in Indy when I got out of school. The 302 cid Z28's did have a problem with pumping the pan dry. A lot of it could have been abuse.... not enough oil to start with and too many rpm's. They'd usually spin 1 and 2 or fly apart. I remember getting a repair order to check a Z28 for a blown engine. You never know what the customer told the service writer. It could be anything. I got in the car and was going to drive it into the bay when I noticed the beam of a connecting rod sitting on top of the console. You see it all when you work in a large dealership.

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I know guys that raced those things off the warantee book. LOL Probably the hardest driven new GM cars ever.

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Of course, they had 5 year 50,000 mile drivetrain warranties back then. Rumor was that the Zone reps for Chevrolet and Chrysler were showing up at IRP on the weekends taking license plate numbers. There was a lot of other funny business going on back then as well.

Ex: A buddy drives in with a '69 Z28 complaining about chattering and whining noises coming from the rear end. With a little "persuasion", the stock 3.73 and carrier unit comes out and a new #4 carrier, bearings, clutches and 4.10 r&p goes back in.

You saw that kind of thing happen quite often. I had buddies that worked at Chrlysler dealers and the same thing went on there too. Bob Glidden worked at the Ford dealer right down the street from me. I can't speak for what went on there.

The dealer I worked at had 2 brand new '69 ZL1's sitting out front. Wish I had one of those now.

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If we did we could retire, right?

Re: High oil pressure?
 

And have money left over. They are now worth about $1m each if they are original. (As defined by the auction/collector guidelines) There's a lot of funny business going on there too.

The last funny deal I read about online, technically only required (as verified documentation) the oem vin tag, matching engine and transmission numbers, the title and a portion of firewall with the vin factory stamped on it. (The rest is believed to be lies and deception) Virtually every other part either could not be verified as oem or was allowed to be replaced with restoration components.

Some of so called "restored" and "original" high dollar muscle cars were never real, whole cars to begin with. Just like NHRA, you can manufacture and race your own S/SS car in your shop that was never a real car to begin with. It just has to meet NHRA's specs. There's a major competitive advantage in doing that.

Re: High oil pressure?
 

On a EOM or Mellings pump when the oil is bypassed and peeing back to the pan how does this happen as there is no orface in the pump cover to do this.

That being said on those HV pumps years ago we use to drill another bypass hole in the cover and bleed off the extra oil pressure when the oil was cold but when we did this we never saw pressure go over on the average 72 pounds.

Since Melling has come out with the 10% more volume pumps years ago we have never used a 25% higher volume pump.

That intersting pumping pans dry as where are you going to put 5 quarts of oil in that engines when the pan is dry.

Re: High oil pressure?
 

I wasnt going to post on this subject any more until Carl posted, but I thought why not just one more. Carl is correct, the SBC does not bypass too the pan. It bypasses within itself, that is one reason you dont want the bypass valve to continually open. It by passes withion itself and builds heat. I, just like Carl, have drilled my on relief hole in the pump so that it will bleed back to the pump. Smokey unit showed me that several, several years ago. The reason, from what I understand, that Melling and other companies came out with HV pumps was to move more oil at the low rpm ban. If you go thru their catalog, you will notice that their HV pump does not make as much pressure. They have a pump called HP to do that. Several years ago, I mounted a remote oil filter with a flow meter mounted in the line. I changed the pumps from standard to HP to HV to Select. If the clearances were ok, There was no more oil going thru the engine, UNLESS you change the pressure. If you up the pressure, then it did flow more oil. It only had more capacity to do so if need. The pulsations WAS slightly lower on the HV. I, just as Carl, now use the 10% HV. Oh yes ED, I, like you, have been doing this since the early 60's. And I think I am too old to see something new, but damn I learn something every time I fire the dyno every day. So Ed, you and I are on the right path to still learn. If you learn something new today, call me. I dont want to miss out on anything. I have to keep notes now though. Book is getting full. I crashed my PC other day and I thought I was really screwed, cause my notes was on it. Then my grandson said, dont worry pops, I backed it up in the sky. So guess he has a direct line to the man upstairs or something like that. I told him to write him a letter and get my notes back. He said I would have them this week end. Now that is service my man.
charles

Re: High oil pressure?
 

Yes, I mis-spoke about the bypass. I was trying to get my point across. That, there is no need for a high volume oil pump in a SBC. Cleveland Fords? probably so. Why more oil at idle? absolutely no reason. If somebody has better bearing life with 10% or more pump volume, they need to seriously take a look at what they are doing. The old "big block-style" +25% pumps? Are you kidding??
A few of my old roundy-round customers seemed to worry about their oil pressure dropping to 15 psi at idle after running 25 to 35 laps WOT in Oklahoma summer heat (no oil coolers). Thought they needed high volume pumps to "cure" that. They just didn't know better, but you still have to waste time trying to explain something that was evidently over their heads. GM says 10 psi per 1000 RPM, I have found that to be VERY safe, to say the least. All this was before synthetic oil, btw.

Re: High oil pressure?
 

Ed
I didnt mean to step on your toes, but I havent seen people use 10 psi for 1000rpm and apparently you dont either by your posting as above. Carl and I was just saying there is several ways to get to the oil issues of motors. I have found that a SBC only needs 4.5 gpm and a ford needs 6.5 gpm but every once in a while you get an engine that is an anomaly and for what ever reason needs slightly more. I have always felt that Melling and several oil pump companies are pretty good business people. I have no idea why they built a HV pump but I am pretty sure they knew what they were doing. I can purchase a HV pump for about the same price as a Std pump on my WD account and I lower the spring pressure even more so I dont bang on the unloader all the time. I have always felt that oil is as much a coolant as water and you can get clearances so tight that you do not get volume or at least not enough to carry off the heat and also I feel you want enough pressure to create the hydrodynamic wedge that you need. Many factors go into how much oil you need etc, width of bearing, compression ratio, normally aspirated or not. I have found turbo motors with boost like volume but it doesnt mean you have to flood, just carry the heat off.
Sorry didnt mean to toe step Ed. Just expressing an opinion

Re: High oil pressure?
 

We build a lot of circle track engines for the last 35 years or so and we use a lot of 10552 and 10553 pumps, Plus we building alot of engines with .903 lifter bores which will bleed off a little more oil. But the 10% more volume pumps seem to work very well.

On our Honda rod and 283 main engines we use the standard volume pump and still have to drill another bypass hole to keep the oil pressure under control.

I also use the drve pump which is a low volume drag race pump onn some of my build with zero problems.

Re: High oil pressure?
 

Hello Carl
Havent talked to you in many years. People as old as me and you should have already retired but------. I too use more select pumps now than I did in the past. I also have found the .903 requires more oil than the .842. Big Blocks shows the same requirements. As Ed has said, he is running 40 psi thru the lights. I have several motors running 5 gpm and running less pressure than even that. I look for volume and not pressure and I watch temp coming out of bearings to see if I need more flow.

Re: High oil pressure?
 

Charles, I have Honda rod bearings, std 350" mains and .904 lifters (bushed bores) in mine, and use a pump with shortened gears with a "stuffer" plate to cut volume. With zero wt oil it idles about 15 psi hot, goes to 40 by 2500 RPM. Cold it idles close to 40. Idle speed is 1600.

I don't think sharing what we have learned is stepping on toes.

Take care, Ed

Re: High oil pressure?
 

I am only 51 years old and still have a few miles to go before I retire LOL

Re: High oil pressure?
 

Must be nice! :-)

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lol

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What is it at the finish line?? My Corvette was dancing between 40 and 60 at 1000 feet when the car was on kill. Clutch it and kill it at the finish line or it would go to zero.

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40 psi at the finish line, drops to 25 or so when I put it in neutral (clean neutral Rossler) unless it has zero wt oil, then drops to about 15. 10W30 cold idles at 40. I can't tell much difference watching the gauge between this pump and my old Moroso pump with the 40 psi spring.