Re: Big block oil pump
[Re: Beep Beep]
#1853100
06/20/15 11:03 AM
06/20/15 11:03 AM
|
Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
|
your cruise psi is higher than needed but not a dealbreaker by any means. #1 pick the thinnest weight of oil you can get by with for your app. use the lowest level of pump/spring combo to maintain 8 psi per 1K of RPM. levels are std pump/std spring std pump stiff spring hi vol pump std spring hi vol pump stiff spring. use just what you need as more stresses/wears the cam gear/inter gear/intergear bushing, again not a dealbreaker. Your idle psi can be lower than what you have & if it jumps up immed when you punch it you are fine. I'd be more wanting to do extensive oiling mods first then pick the wt then pick the pump/spring. bottom line as you know is can your pump/spring maintain enough psi & the rods are the end of the line/critical area, #1 #1 are they getting fed properly.
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: Big block oil pump
[Re: Beep Beep]
#1853828
06/21/15 03:32 PM
06/21/15 03:32 PM
|
Joined: Oct 2003
Posts: 4,013 South Park, Pa.
68LAR
master
|
master
Joined: Oct 2003
Posts: 4,013
South Park, Pa.
|
What is working for me is a HV pump with 15w/40 Rotilla T. I did the oiling mods to the block except for the 3/8" oil pick. I'm not a professional racer, by no means, every hundredths of a second mean nothing to me. You might call me a "weekend warrior", at best, at times. When cold my idle pressure is close to 90 psi. At temp. (160*), my idle,(1200 rpm) pressure is 55 psi. At 2000 rpm it holds steady at 65 psi. The most I try to rev the engine to is 6500 rpm. Just sharing my experience. Have fun....
4 speed street legal. Best time 10.99 @ 124 mph on 93 octane pump gas @ 3926# total weight
|
|
|
Re: Big block oil pump
[Re: lewtot184]
#1853915
06/21/15 06:33 PM
06/21/15 06:33 PM
|
Joined: Jan 2003
Posts: 25,949 Rio Linda, CA
John_Kunkel
Too Many Posts
|
Too Many Posts
Joined: Jan 2003
Posts: 25,949
Rio Linda, CA
|
High-volume pumps come with the high-pressure spring.
The INTERNET, the MISinformation superhighway
|
|
|
Re: Big block oil pump
[Re: lewtot184]
#1853997
06/21/15 10:18 PM
06/21/15 10:18 PM
|
Joined: Apr 2015
Posts: 114 Oregon
Wagonman1967
member
|
member
Joined: Apr 2015
Posts: 114
Oregon
|
the high volume pumps heavy high pressure spring is taken out and thrown in the junk box in my garage. excessive pressures eat up the intermediate shaft and bushing. the only use for those heavy springs is for bottom end bleeders that can't make pressure any other way. HMMM Makes sense.
1968 Bronze Metalic Road Runner !967 Malibu Wagon Original 4sd w/air 2001 Dodge Ram 4wd 1985 GMC K1500 4in lift 1993 Honda Civic W 350k Beater 2003 Honda VTX 1800 Bagger
|
|
|
Re: Big block oil pump
[Re: Beep Beep]
#1854054
06/21/15 11:51 PM
06/21/15 11:51 PM
|
Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
|
So if I use the high volume pump, and remove the heavy spring which spring do I replace it with?
Do the high volume pumps put extra wear on bearings and the distributor gears?
Does the pressure also increase with the high volume pumps, or is the pressure only affected by the bearing clearances?
(1) one from a stock pump (2) bearings no dist gears yes (3) A I believe it will. B As said psi is a measure of restriction which includes bearings and everything else downstream
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: Big block oil pump
[Re: Beep Beep]
#1854083
06/22/15 12:23 AM
06/22/15 12:23 AM
|
Joined: Aug 2003
Posts: 43,284 Bend,OR USA
Cab_Burge
I Win
|
I Win
Joined: Aug 2003
Posts: 43,284
Bend,OR USA
|
Both of the high volume oil pump brands sold in the U.S. usually have the bypass spring pressure set at 80 lbs, some may be as high as 90 and some may be as low as 70 lbs cold, depending on the oil viscoty and outside air temps. I would never throw a new Hi Po part in the trash, I would and do trim them (the bypass springs )or grind(slowly a little bit at a time to avoid overheating from grinding) them down to reduce the overall lengths to get the pressures I want The longer rotors do suck in more oil and provide more volume of oil into the motor, the oil pump can only pump as much oil as the motor will take before the bypass spring and valve opens, kicks in, and starts bypassing oil back into the pump. I do set my rod and main bearings up with a lot of clearance(.0032+ on both) so I get a lot of oil flowing through the motor while running, you need to remember that the cam is oiled from the bottom by splash oiling slung from the crankshaft assembly so it is hard to over oil it IHTHs As far as bronze distribotor oil pump drive gears there are soft ones out there and there are good ones, the good ones last a lot longer than the soft ones do I've seen both used in other builders motors and seen the soft ones fail on the dyno breaking in and testing the motor
Last edited by Cab_Burge; 06/22/15 12:25 AM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
|
|
|
Re: Big block oil pump
[Re: Beep Beep]
#1854472
06/22/15 05:26 PM
06/22/15 05:26 PM
|
Joined: Jan 2003
Posts: 25,949 Rio Linda, CA
John_Kunkel
Too Many Posts
|
Too Many Posts
Joined: Jan 2003
Posts: 25,949
Rio Linda, CA
|
So if I use the high volume pump, and remove the heavy spring which spring do I replace it with?
Generally speaking, the high pressure spring is painted black or natural color, the standard pressure spring is painted red.
The INTERNET, the MISinformation superhighway
|
|
|
Re: Big block oil pump
[Re: Cab_Burge]
#1854526
06/22/15 06:33 PM
06/22/15 06:33 PM
|
Joined: Jun 2008
Posts: 3,916 usa
lewtot184
master
|
master
Joined: Jun 2008
Posts: 3,916
usa
|
Both of the high volume oil pump brands sold in the U.S. usually have the bypass spring pressure set at 80 lbs, some may be as high as 90 and some may be as low as 70 lbs cold, depending on the oil viscoty and outside air temps. I would never throw a new Hi Po part in the trash, I would and do trim them (the bypass springs )or grind(slowly a little bit at a time to avoid overheating from grinding) them down to reduce the overall lengths to get the pressures I want The longer rotors do suck in more oil and provide more volume of oil into the motor, the oil pump can only pump as much oil as the motor will take before the bypass spring and valve opens, kicks in, and starts bypassing oil back into the pump. I do set my rod and main bearings up with a lot of clearance(.0032+ on both) so I get a lot of oil flowing through the motor while running, you need to remember that the cam is oiled from the bottom by splash oiling slung from the crankshaft assembly so it is hard to over oil it IHTHs As far as bronze distribotor oil pump drive gears there are soft ones out there and there are good ones, the good ones last a lot longer than the soft ones do I've seen both used in other builders motors and seen the soft ones fail on the dyno breaking in and testing the motor anybody who knows anything about spring rates knows that trimming springs doesn't reduce the spring rate.
|
|
|
Re: Big block oil pump
[Re: John_Kunkel]
#1854528
06/22/15 06:37 PM
06/22/15 06:37 PM
|
Joined: Jun 2008
Posts: 3,916 usa
lewtot184
master
|
master
Joined: Jun 2008
Posts: 3,916
usa
|
So if I use the high volume pump, and remove the heavy spring which spring do I replace it with?
Generally speaking, the high pressure spring is painted black or natural color, the standard pressure spring is painted red. all the originals were red. i've seen and have pink and natural colored "stock" springs from aftermarket stock pumps. this is why i measure the length and wire diameters to try and get an "apples to apples" comparison. never know what your buying anymore.
|
|
|
Re: Big block oil pump
[Re: lewtot184]
#1854644
06/22/15 08:00 PM
06/22/15 08:00 PM
|
Joined: Aug 2003
Posts: 43,284 Bend,OR USA
Cab_Burge
I Win
|
I Win
Joined: Aug 2003
Posts: 43,284
Bend,OR USA
|
Both of the high volume oil pump brands sold in the U.S. usually have the bypass spring pressure set at 80 lbs, some may be as high as 90 and some may be as low as 70 lbs cold, depending on the oil viscoty and outside air temps. I would never throw a new Hi Po part in the trash, I would and do trim them (the bypass springs )or grind(slowly a little bit at a time to avoid overheating from grinding) them down to reduce the overall lengths to get the pressures I want The longer rotors do suck in more oil and provide more volume of oil into the motor, the oil pump can only pump as much oil as the motor will take before the bypass spring and valve opens, kicks in, and starts bypassing oil back into the pump. I do set my rod and main bearings up with a lot of clearance(.0032+ on both) so I get a lot of oil flowing through the motor while running, you need to remember that the cam is oiled from the bottom by splash oiling slung from the crankshaft assembly so it is hard to over oil it IHTHs As far as bronze distribotor oil pump drive gears there are soft ones out there and there are good ones, the good ones last a lot longer than the soft ones do I've seen both used in other builders motors and seen the soft ones fail on the dyno breaking in and testing the motor anybody who knows anything about spring rates knows that trimming springs doesn't reduce the spring rate. Let's see, if we reduce the overall length of the spring, especially when it is already compress some,loaded under compression, and the oil pressure drops when hot after shortening the spring, I assumed that reduced the oil pressure, which was exactly what I wanted to accomplish My training on springs, if my memory is serving me half way accurately now,is shortening the spring increases the unloaded spring rating, is that correct or not
Last edited by Cab_Burge; 06/22/15 08:01 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
|
|
|
Re: Big block oil pump
[Re: Cab_Burge]
#1854728
06/22/15 09:34 PM
06/22/15 09:34 PM
|
Joined: Jan 2003
Posts: 12,240 Benton, IL.
DaveRS23
Special needs idiot
|
Special needs idiot
Joined: Jan 2003
Posts: 12,240
Benton, IL.
|
I have always had good luck either trimming the springs a little to lower the pressure or shimming them to gain some pressure. I understand that doing either one does not change the spring's rate, but I can tell that doing one or the other almost always changes my oil pressure. Just my
Master, again and still
|
|
|
Re: Big block oil pump
[Re: ragin sonny]
#1855247
06/23/15 03:32 PM
06/23/15 03:32 PM
|
Joined: Jan 2003
Posts: 25,949 Rio Linda, CA
John_Kunkel
Too Many Posts
|
Too Many Posts
Joined: Jan 2003
Posts: 25,949
Rio Linda, CA
|
If you take a close look at the design of the relief valve in a BB pump, you'll notice that the "window" opening for the relief flow is pretty small....small enough, in fact, that it can't always handle the excess pressure even when wide open. That's why HV pumps with a 60 lb. spring can reach 80+ PSI...excess volume that the relief can't handle equates to excessive pressure.
The INTERNET, the MISinformation superhighway
|
|
|
Re: Big block oil pump
[Re: ragin sonny]
#1855411
06/23/15 07:14 PM
06/23/15 07:14 PM
|
Joined: Aug 2003
Posts: 43,284 Bend,OR USA
Cab_Burge
I Win
|
I Win
Joined: Aug 2003
Posts: 43,284
Bend,OR USA
|
does anybody use the milodon adjustable set screw set up? seems it would be the answer. I always wanted to try one. I have used those, I have a factory cover that someone made into a copy of the adjustable Milidon setup, you could to they drilled and tapped the relief cover, plug, and went from there, if I wasn't so lazy and busy I would learn how to post pictures on here now and take one for you, maybe later this evening. BTW I didn't like the adjustable set ups so I replace them with a stock relief plug and trimmed the bypass springs to get the pressure I wanted
Last edited by Cab_Burge; 06/23/15 07:15 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
|
|
|
Re: Big block oil pump
[Re: John_Kunkel]
#1855420
06/23/15 07:24 PM
06/23/15 07:24 PM
|
Joined: Jan 2003
Posts: 31,068 Oregon
AndyF
I Win
|
I Win
Joined: Jan 2003
Posts: 31,068
Oregon
|
If you take a close look at the design of the relief valve in a BB pump, you'll notice that the "window" opening for the relief flow is pretty small....small enough, in fact, that it can't always handle the excess pressure even when wide open. That's why HV pumps with a 60 lb. spring can reach 80+ PSI...excess volume that the relief can't handle equates to excessive pressure. Yep, I learned that lesson years ago when I thought it would be a good idea to run the biggest oil pump possible. I bolted a Milodon pump onto my 426W and ended up with more than 100 psi of pressure. Even with the stock bypass spring the pump was so big that it just generated a ton of oil pressure as all of that oil tried to go somewhere. Even the HV pump is too big for some engines and the Milodon pump is way too big for most motors. It was designed for funny cars back in the day when they ran really loose bearing clearances. Just goes to prove that bigger isn't always better.
|
|
|
Re: Big block oil pump
[Re: DaveRS23]
#1855931
06/24/15 02:45 PM
06/24/15 02:45 PM
|
Joined: Jan 2003
Posts: 16,376
dogdays
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 16,376
|
I like to see when folks get something right.
Mr. Cab, your understanding of coil springs is correct. Cutting coils off the spring reduces the length of spring wire that is active, so the same deflection of the spring requires the wire to twist more than originally with the longer wire.
Standing back and looking at it, it appears to me that the pressure relief system in the average oil pump is very imprecise. I think there must be a better way. Problem is, we're dealing with a design from am manufacturer that needs to cut costs and the existing system works well enough once you get it down empirically.
Regarding pumping power: Pump Horsepower = Pressure x Volume x a constant. That's set in stone, there's no way of getting around that fact. You can calculate torque by using the equation once you know the rpm and horsepower. This too is all math.
The deal is that bigger pumps and higher pressures require more horsepower to operate. That horsepower comes from the gear drive. So in loading the system with a bigger pump or higher operating pressure, the gear drive needs to provide more power which means it transmits more torque. Torque is what causes the shaft to snap or loads the gears on the gear drive.
At least the B/RB engines have the oil pump at the front. In engines with the distributor/oil pump at the rear, the loading of the oil pump causes the camshaft to deflect torsionally, meaning the rear cylinders see different valve timing events than the fronts. So in these engines, adding a larger pump may cause power loss in two ways.
My Toyota 20R engine was the first engine I had apart that ran the oil pump directly off the crankshaft. What a concept!
On the other hand my friend's Mercedes 280SEL4.5 had the oil pump mounted in the oil pan, run from the crankshaft by a roller (bicycle) chain. The Mercedes of that day used a two part oil pan, top was cast aluminum and there was a bolt-on steel sump. The interior of the aluminum upper pan had fingers that reached up and acted like a crank scraper, also directed the oil into the sump. It was a thing of beauty. The lower third, the steel sump pan, was replaceable in case of damage, also the formed steel sump was more resistant to cracking on impact. Those guys really went all out.
R.
|
|
|
|
|