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Re: High Volume vs Standard Volume Oil Pump
[Re: B G Racing]
#1337700
11/20/12 01:16 PM
11/20/12 01:16 PM
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Joined: Jan 2003
Posts: 9,875
Weddington, N.C.
Streetwize
master
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master
Joined: Jan 2003
Posts: 9,875
Weddington, N.C.
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Bob, That's a GREAT point with the Hemis and it really amazes me how much oil (quantity) meters through a motor during a full throttle pass. The hemi head has (I'm guessing) probably more than twice the oil coated surface area for oil to collect up top and drainback to the sump is far more of an issue, so it's logical that the more oil that is (for want of a better word) "dwelling" on an engine surface and not draining immediately to the pan has to be made up for in the system volume. It hasn't been mentioned here but Oil flow is also a critical cooling component as it wicks away heat from all of the engine surfaces, and on a drag car the valve springs particularly.  FWIW, Bob's tip of run the HV and an extra quart was the way we used to do it 30+ years ago and I never lost a bottom end to oil related failures, even at 8200 rpm in a W2 340 which was wound pretty tight for a street motor in the late 70's-early 80's. And the front sump design of the Typical A,B, E bodies didn't help things either!
Last edited by Streetwize; 11/20/12 01:22 PM.
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Re: High Volume vs Standard Volume Oil Pump
[Re: Streetwize]
#1337701
11/20/12 01:31 PM
11/20/12 01:31 PM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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Quote:
Bob,
That's a GREAT point with the Hemis and it really amazes me how much oil (quantity) meters through a motor during a full throttle pass.
The hemi head has (I'm guessing) probably more than twice the oil coated surface area for oil to collect up top and drainback to the sump is far more of an issue, so it's logical that the more oil that is (for want of a better word) "dwelling" on an engine surface and not draining immediately to the pan has to be made up for in the system volume.
It hasn't been mentioned here but Oil flow is also a critical cooling component as it wicks away heat from all of the engine surfaces, and on a drag car the valve springs particularly.
FWIW, Bob's tip of run the HV and an extra quart was the way we used to do it 30+ years ago and I never lost a bottom end to oil related failures, even at 8200 rpm in a W2 340 which was wound pretty tight for a street motor in the late 70's-early 80's. And the front sump design of the Typical A,B, E bodies didn't help things either!
 Circulation helps with the cooling also.With a hemi the large area of trapped or retained oil at the top is a critical issue,also the poor drainback design(holes at each corner of the heads)is a concern.On many of our large high hp engines we add two drain back lines per side to help return the oil to the sump.
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Re: High Volume vs Standard Volume Oil Pump
[Re: Thumperdart]
#1337703
11/20/12 03:21 PM
11/20/12 03:21 PM
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Joined: Oct 2003
Posts: 1,409
Ont. Canada
10.90 Racer
super street
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super street
Joined: Oct 2003
Posts: 1,409
Ont. Canada
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Quote:
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personally i think the HV pump sucking the pan dry is a wives tale.
I will send you my burnt rod.....Was running 9.5 quarts, and starved one rod.
You my friend MAY have other problems..........I run 5w30 Mobile-1 and w/6-quarts in an 8-quart pan and a hv pump I never hurt anything and my bearings looked real good after 7 years of street/strip thrashing........... 
^ 
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Re: High Volume vs Standard Volume Oil Pump
[Re: Mopar Guy]
#1337706
11/20/12 05:34 PM
11/20/12 05:34 PM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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It's not any theory of mine,but something that Chrysler engineers had proclaimed and informed racers of years ago that on a adverage 10 second pass at aprox. 8000rpm and to retain enough volume in the sump 10 quarts would need to circulate 3Xs.I've never had any reason to confirm or refute this claim,but had an incident where Mark Davis and I was testing a Milodon dual line system with a drill and 2 five gallon buckets with 8 quarts of oil.While priming the pump up to about 1800rpm,Mark found himself covered in most the 8 quarts before he could face the pump outlet to the second bucket and I could release the drill trigger alot less than 10 seconds.Also keep in mind that at any given rpm that more than 1/2 the sump volume is in the engine not the pan.Also consider the amont of oil in a drysump system that does circulate on even quicker passes. We need also to consider some adverage bracket engine that have 10quart sumps and 3quart accumulators(13qts)and at the end of the pass when the pressure drops on hard decel and accumulator has to back up the system,where is all that oil. I'am not going to say my refrence of the claim and findings of Chrysler engineers of 1970s is the final fact,but I'll buy it till someone can prove otherwise.Maybe it's a sales gimmick to get us to buy big pumps,pans and tons of oil.Maybe someone will try the Mark and Bob experiment with a stopwatch and report back to us. 
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Re: High Volume vs Standard Volume Oil Pump
[Re: B G Racing]
#1337707
11/20/12 06:18 PM
11/20/12 06:18 PM
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Joined: Oct 2003
Posts: 1,409
Ont. Canada
10.90 Racer
super street
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super street
Joined: Oct 2003
Posts: 1,409
Ont. Canada
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Quote:
It's not any theory of mine,but something that Chrysler engineers had proclaimed and informed racers of years ago that on a adverage 10 second pass at aprox. 8000rpm and to retain enough volume in the sump 10 quarts would need to circulate 3Xs.I've never had any reason to confirm or refute this claim,but had an incident where Mark Davis and I was testing a Milodon dual line system with a drill and 2 five gallon buckets with 8 quarts of oil.While priming the pump up to about 1800rpm,Mark found himself covered in most the 8 quarts before he could face the pump outlet to the second bucket and I could release the drill trigger alot less than 10 seconds.Also keep in mind that at any given rpm that more than 1/2 the sump volume is in the engine not the pan.Also consider the amont of oil in a drysump system that does circulate on even quicker passes.
We need also to consider some adverage bracket engine that have 10quart sumps and 3quart accumulators(13qts)and at the end of the pass when the pressure drops on hard decel and accumulator has to back up the system,where is all that oil.
I'am not going to say my refrence of the claim and findings of Chrysler engineers of 1970s is the final fact,but I'll buy it till someone can prove otherwise.Maybe it's a sales gimmick to get us to buy big pumps,pans and tons of oil.Maybe someone will try the Mark and Bob experiment with a stopwatch and report back to us.
You have to remember, most of the oil is just pumping against resistance . The amount of oil actually flowing is what all the bleed off clearances in the engine will allow...........
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Re: High Volume vs Standard Volume Oil Pump
[Re: 10.90 Racer]
#1337708
11/20/12 07:04 PM
11/20/12 07:04 PM
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Joined: Jan 2003
Posts: 5,875
communist bloc of new jersey
jamesc
master
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master
Joined: Jan 2003
Posts: 5,875
communist bloc of new jersey
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Quote:
You have to remember, most of the oil is just pumping against resistance . The amount of oil actually flowing is what all the bleed off clearances in the engine will allow...........
exactly, and people need to get hold of this fact
the milidon pump (according to them and i think they're actually BB ford rotors) is rated at 19-21 GPM of course this is speed dependent but one would have to think that they rated it at a decent speed
these things determine how much oil is actually FLOWING THROUGH the engine
> oil pressure
> clearances (leaks)
> oil viscosity (temperature impacted)
because oil pumps are positive displacement they MUST have a relief system which is the function of the relief spring and valve. any oil that the pump is moving that is not required to maintain the pressure that the relief valve is set at spills from the discharge directly back into the suction. it is simply pumped in circles, the amount of oil pumped by a PD pump is directly proportional to its speed.
oil pumps, hydraulic pumps, roots and screw type blowers are all examples of a positive displacement pump, for each rotation they move an exact amount of fluid.
i have seen PD hydraulic pump bodies literately split in half when they were not protected by a relief valve and someone started the engine with the pump discharge closed.
water pumps, turbochargers, pro chargers are all examples of centrifugal pumps, these type pumps allow for "slip" meaning you can block the discharge and the pump won't lock it will slip.
because of their design centrifugal pumps/compressors are subject to a phenomenon know as surge and i'm not even going to try to explain that and NPSH here
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Re: High Volume vs Standard Volume Oil Pump
[Re: Cab_Burge]
#1337709
11/20/12 11:17 PM
11/20/12 11:17 PM
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Joined: Jan 2003
Posts: 16,925
NC
440Jim
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,925
NC
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Quote:
I use the same oil pan I use 5W20WT Valvoline non synthetic, I have to keep the oil level above the add mark at the drag strip, if I don't the oil pressure will drop off when I let off.
That pan is known to have issues during deceleration (braking). But if you keep the oil level high enough, it will be fine.
As far as the std vs high volume oil pump, IMO it has more effect at idle than anywhere else. If the std gives you at least 15 psi at hot idle, I would run it. Otherwise go with the high volume. This can be very sensitive to idle speed (700 rpm or 900 rpm), so running a couple hundred more rpm can solve some low pressure issues at hot idle.
FWIW,
In my 511 CID wedge big block, I have run both a HV pump and a std volume pump with the internals smoothed. Using the same bypass spring in both pumps, the oil pressure going down the track was identical. The only difference was the idle oil pressure, most notably only when the oil was hot (which is hard to do in a drag race car). After one season with the std volume pump, the inside looked great (bearings, crank, pistons, etc.). But I didn't see any ET improvement. I think drain back and the amount going to the heads (mine has Indy heads with restrictors) along with oil pan is more important than the pump volume.
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Re: High Volume vs Standard Volume Oil Pump
[Re: B G Racing]
#1337712
11/21/12 07:51 PM
11/21/12 07:51 PM
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Joined: Jan 2003
Posts: 1,361
Wild West
M_D
pro stock
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pro stock
Joined: Jan 2003
Posts: 1,361
Wild West
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Quote:
Race engines with bigger clearences need more volume. Oil systems is not a place to gamble or skimp on. 
I agree, enlarging clearances will require more volume of flow to maintain the same pressure, all other things being more or less equal. But, that doesn't automatically mean a standard pump won't work, it may or may not, depending on the exact factors involved which primarily amount to pump capacity and the flow needed to have sufficient pressure with given clearances. If the pressure is adequate, which indicates the flow is also adequate for that combination, then installing a larger pump will just bypass more oil assuming the pressures are equal.
Let's compare this to flow bench principles. The flow bench is adjusted to maintain the same pressure as the test is repeated at various valve lifts. When a port flows more air, you increase the volume of air being pulled (or pushed) through it until the pressure equals the standard you are using. Having a means to regulate pressure (a bypass or return) allows pumps to work over a certain range of flows. So, as long as a flow bench is capable of pumping enough air to reach the desired test pressure a large bench (pump) will not gain anything as you just bypass or regulate the flow downward to keep the pressure in check.
My 2 cents on the oil pumps is a bigger (within reason) pump is better than one too small, but it isn’t better than one that is smaller but big enough.
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Re: High Volume vs Standard Volume Oil Pump
[Re: M_D]
#1337713
11/21/12 07:57 PM
11/21/12 07:57 PM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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Quote:
Quote:
Race engines with bigger clearences need more volume. Oil systems is not a place to gamble or skimp on.
I agree, enlarging clearances will require more volume of flow to maintain the same pressure, all other things being more or less equal. But, that doesn't automatically mean a standard pump won't work, it may or may not, depending on the exact factors involved which primarily amount to pump capacity and the flow needed to have sufficient pressure with given clearances. If the pressure is adequate, which indicates the flow is also adequate for that combination, then installing a larger pump will just bypass more oil assuming the pressures are equal.
Let's compare this to flow bench principles. The flow bench is adjusted to maintain the same pressure as the test is repeated at various valve lifts. When a port flows more air, you increase the volume of air being pulled (or pushed) through it until the pressure equals the standard you are using. Having a means to regulate pressure (a bypass or return) allows pumps to work over a certain range of flows. So, as long as a flow bench is capable of pumping enough air to reach the desired test pressure a large bench (pump) will not gain anything as you just bypass or regulate the flow downward to keep the pressure in check.
My 2 cents on the oil pumps is a bigger (within reason) pump is better than one too small, but it isn’t better than one that is smaller but big enough.
All things being equal,"bigger is always better"If two good look guys went out on the town and one came up shorter than the other,which one has a better chance of getting lucky? 
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Then again, do you look for dates that probably have big clearances? 