Opinions on 440 oil pumps

[ottawamerc]

Hi guys / gurus

I'm thinking of changing the oil pump on my "just built" 440 6 pack. The one that is in there is fine I guess but its just a OEM stock pump. I was wondering what type of pump you guys are running or would recommend? Looking for your 

Thanks guys
Scott

[ws23rt]

If you are looking for   worth I always have that. You say yours is fine and it most likely is after all it is what they made for that engine. I always like to move up a bit to a high volume pump and am not sure why. Maybe a just in case sense I have. I think my reason is as the pump losses newness it would pump less and a high volume pump may pickup the difference. I am assuming your use for the engine is what the makers intended.

[John_Kunkel]

If your existing pump maintains pressure throughout the rpm range leave it alone.

[Cooter]

I've read HV oil pumps do tend to rob HP and drain a pan dry at high RPM's. If the stock pump is doing ok, then it should be ok. I have a stock pump on my pig motor in the GL and it does just fine.

Many times with a HV pump when cold, it will hold near 80-90 PSI. I haven't had it happen to me, but have heard horror stories bout blowing the little plastic line off the back and spraying oil everywhere.

[ws23rt]

I've read HV oil pumps do tend to rob HP and drain a pan dry at high RPM's. If the stock pump is doing ok, then it should be ok. I have a stock pump on my pig motor in the GL and it does just fine.

Many times with a HV pump when cold, it will hold near 80-90 PSI. I haven't had it happen to me, but have heard horror stories bout blowing the little plastic line off the back and spraying oil everywhere.

On that same line I had a warning from an oil cooler vender about over pressure in the system. They wanted to make sure that if their product sprung a leak it would be your fault not theirs.

[ottawamerc]

Ok message received.. I have had no reason to worry about the pump and I dont plan on beating the hell out of the new engine. 20 yrs ago I had a similar setup with a HV pump and it did suck the engine dry on hard accelerations. I just thought there might have been some improvements since then.

Thanks for the input

Scott

[A383Wing]

probably didn't "suck the engine dry" on acceleration.....I bet the oil just ran to rear of pan due to no baffles.

Bryan

[ws23rt]

probably didn't "suck the engine dry" on acceleration.....I bet the oil just ran to rear of pan due to no baffles.

Bryan

I agree with that. And if the oil level is low it is much more likely that that happens.  The bearings need just a whisper of oil at minimum the extra just goes back around.

[Cooter]

Don't know how much truth is in it, but I did see a set of rod/main bearings at my machinists shop that had a groove 'Cut' in them from what he believed was too much oil pressure.

[68CoronetRT]

Alot of my research has concluded that a HV pump is OK as long as you run the deep 7-8qt oil pans.

Personally I'm running a HV pump with the deep pan. But this is also my first Mopar build and I have no idea what will happen.

If I was running the stock oil pan I would just go with a stock pump, or the "hemi" pump I guess?

[69rtse4spd]

Got a high volume pump on my 446, 6-pack, with the 6-quart pan. Bet the crap out of it, no problems yet. 

[heyoldguy]

If you use a high volume oil pump, a high pressure oil pump or a standard oil pump and set the relief spring so that you get 60# of oil pressure on all of them, they will pump EXACTLY THE SAME AMOUNT of oil volume THROUGH THE ENGINE. The volume of oil the engine uses is determined by the engine clearances, oil viscosity and the oil pressure you use. A benefit of the high volume pump is it can maintain the oil pressure if the clearances increase. Oil pressure is a measure of resistance to oil flow through the engine. Same pressure + same resistance = same volume of flow no matter how big the pump involved.

[firefighter3931]

If you use a high volume oil pump, a high pressure oil pump or a standard oil pump and set the relief spring so that you get 60# of oil pressure on all of them, they will pump EXACTLY THE SAME AMOUNT of oil volume THROUGH THE ENGINE. The volume of oil the engine uses is determined by the engine clearances, oil viscosity and the oil pressure you use. A benefit of the high volume pump is it can maintain the oil pressure if the clearances increase. Oil pressure is a measure of resistance to oil flow through the engine. Same pressure + same resistance = same volume of flow no matter how big the pump involved.

Well said !  

Personally, i like a HV pump but i run my rod & main bearing clearances a little on the loose side to allow for thermal expansion. With .0025 on the mains/rods i can keep hot oil pressure at 45-50psi and it will shoot up to 70-75 at 6000rpm. This is with Brad Penn 20/50 semi synthetic race oil.

On my old 446 i had the HV pump with a street hemi oilpan and a stock windage tray. Rock solid oil pressure allways.....even when racing under hard acceleration/deceleration. The baffleing in the hemi pan along with the windage tray certainly keeps oil under control....and the sump full at all times.

I guess it really depends on the current setup and what type of bearing clearances the OP has in his engine ? Any loss of pressure ? If so....when is it dropping ? What is the capacity of the current system ? Windage tray ? Oil viscosity ?


Ron

[Cooter]

I guess the factory Figured this out and began to mandate 5/30 oils, but I read a dyno thrash test against 20/50 oil VS 5/30 oil.


"At 80 psi this 383 had an abundance of oil pressure, so we decided to drain the 20W50 weight oil in favor of 5W30. The thinner oil will be easier to pump, and should free up some power. Of course, we wouldn't recommend this for an engine that has marginal oil pressure, but we only lost 5 psi which lowered our oil pressure to 75 psi. It worked, as we gained 16 horesepower."


http://www.moparmusclemagazine.com/techarticles/engine/mopp_1206_383_big_block_engine_build_part_2/holley_double_pumper_carburetor.html

[jlatessa]

You better pump a lot of oil with .025 on your mains, Firefighter

Joe

[firefighter3931]

You better pump a lot of oil with .025 on your mains, Firefighter

Joe

Ooops....meant .0025   

Thanks Joe 


Ron

[Budnicks]

You better pump a lot of oil with .025 on your mains, Firefighter

Joe

yeah at 25 hundreths you would need a freighter full    typo