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daveh 03-06-2013 10:43 AM

Which Oil Pump
 
Hey guys,

I'm looking to replace my oil pump in my slightly modified 1971 Challenger 340with one of these since I recently bought a higher capicity oil pan. Any pros or cons are greatly appreciated.

Mopar Performance High Performance Oil Pumps P4286589 - SummitRacing.com

Melling High-Volume Oil Pumps M-72HV - SummitRacing.com

Sealed Power High-Volume Oil Pumps Z2244166V - SummitRacing.com

Thanks
Dave

33Willys77 03-06-2013 10:54 AM

The Melling or MP will flow 20-25% more. Either one would work for you. These are the 2 I would stick with for your application.

snakebit68 03-06-2013 11:21 AM

oil pump
 
I've always been a big fan of Melling as they adhere to a strict quality control program. Its a personal choice, but oil pumps are not the area to take a shortcut or inexpensive route on.

spinn 03-06-2013 11:41 AM

My 318 is 30 over. Has the 340 adjustable rockers and 340 cam. 051 heads 1.88/1.60 valves. The valiant it was in had 3.31 gears. Edelbrock 600 on streemaster 318 0-5000rpm single plane. If your setup is like this the melling standard output is fine.

Make sure the pickup is clearanced to the pan floor.

ap72 03-06-2013 11:56 AM

Melling pump, but when you get it pop it open and take it apart and smooth out everything, it can make a big difference and is relatively easy to do.

oldbogie 03-06-2013 12:38 PM

Quote:

Originally Posted by daveh (Post 1654107)
Hey guys,

I'm looking to replace my oil pump in my slightly modified 1971 Challenger 340with one of these since I recently bought a higher capicity oil pan. Any pros or cons are greatly appreciated.

Mopar Performance High Performance Oil Pumps P4286589 - SummitRacing.com

Melling High-Volume Oil Pumps M-72HV - SummitRacing.com

Sealed Power High-Volume Oil Pumps Z2244166V - SummitRacing.com

Thanks
Dave

Depends, have more capacity in the pan doesn't mean you need a higher volume pump. It's good to have the extra capaicty but what's really needed is oil management in the pan. By that I mean trap doors to keep the oil around the pickup, and a windage tray and stripper to peel the goo from the crankshaft. High volume pumps really require attention to the details of oil windage as the extra volume of oil passing through the bearings as well as top end drainback can easily overwhelm the piston's oil control rings, this especially can get to be a problem with loosely fitted pistons, high silicon with close clearance to the cylinder walls are less of a problem, but old fashion cast pistons or those forgings from 2618 alloy can really result in an oil burner that won't quit as both like and need a loose skirt clearnace which lets the piston thus the ring package rock in the bore making it hard for the rings to seal up.

I'm not too crazy for high volume standard pressure pumps unless the bearing clearances are on the loose side. That lets the oil flow through the bearing quickly so that extra volume from the pump actually circulates. When the bearing clearances are production standard, especially if on the tight side, the extra oil flow from a high volume pump can't get out of the clearance fast enough. That creates a back pressure on the pump which when combined with a standard pressure relief valve ends up with the valve open most all time which is just wasted effort that heats and foams the oil while putting extra mechanicial loading on the entire cam drive system (read that power extraction as well as part wear) to drive the pump. The small block Chrysler when raced does show some oil system inadaquacies but these are not simply sensitve to volume and pressure increases for a solution. For a street engine, including a performance street engine, oil system changes to this engine are not necessary.

In the condition of a high volume with high pressure pump it is likely that the relief valve is not open so much of the time when the high volume backs up against close bearing clearances, but the wear and power extration figures remain on the cam and oil pump drive systems.

Whatever your decision on the pump, carefully disassemble the selected pump and inspect it for all the fits and clearances. We see enough problems with pumps to warrant this extra attention, it is way easier to fix errors and left in machining shavings before the engine is either fired up or heaven forbid fired up after installtion then to discover problems within the pump.

Bogie

daveh 03-06-2013 01:01 PM

Thanks guys from all of the replys it sounds like I should go with the Melling standard volume pump below since the 340 isn't built over the top. All I know from the previous owner is that it's punched out 30 over with a purple cam and forged pistons. Looks like standard rockers nothing special.

Melling Oil Pumps M-72 - SummitRacing.com

Dave

ap72 03-06-2013 02:33 PM

Quote:

Originally Posted by daveh (Post 1654140)
Thanks guys from all of the replys it sounds like I should go with the Melling standard volume pump below since the 340 isn't built over the top. All I know from the previous owner is that it's punched out 30 over with a purple cam and forged pistons. Looks like standard rockers nothing special.

Melling Oil Pumps M-72 - SummitRacing.com

Dave

high volume pumps are for low rpm protection, not high RPM.

Once the bypass opens the high volume will flow no more than a standard pump- BUT below it (lower RPM) you will have more flow and pressure. I like them for street cars especially ones that have shallow gears (low rpm most of the time).

High volume pumps work well at lower rpm, but at higher rpm the standard pump actually works better- where the crossover is depends on clearances, oil viscosity, temp, and your relief spring pressure.

daveh 03-07-2013 07:07 AM

Hey guys I'd like to make a decision today so I can order the pump. I've got it narrowed down to either the high volume Melling or the standard Melling pump.

Melling High-Volume Oil Pumps M-72HV - SummitRacing.com

Melling Oil Pumps M-72 - SummitRacing.com

I'm leaning towards the standard because my engine really isn't that radical. The only reason I was asking about the HV pump is because of the deeper pan that I'm installing.

Any further suggestions will be greatly appreciated. Thanks

Dave

ap72 03-07-2013 10:19 AM

Quote:

Originally Posted by daveh (Post 1654379)
Hey guys I'd like to make a decision today so I can order the pump. I've got it narrowed down to either the high volume Melling or the standard Melling pump.

Melling High-Volume Oil Pumps M-72HV - SummitRacing.com

Melling Oil Pumps M-72 - SummitRacing.com

I'm leaning towards the standard because my engine really isn't that radical. The only reason I was asking about the HV pump is because of the deeper pan that I'm installing.

Any further suggestions will be greatly appreciated. Thanks

Dave

Not radical daily drive street engines are where the HV pump is of good use. High RPM engines can actually do worse with a HV pump. I think you misunderstand what a HV pump does.


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