On this combo...
'71 440 Block .30 over
All neccesary machine work/ fully balanced
Block square decked
Ross 99539 pistons/ 2.065 Comp. Height
New Scat Rods
Full Grooved mains/HV Oil pump
Lunati 60304 cam/lifters
440 Source stealth heads/Crane Ductile adjustable rockers, bushed by RAS/ Bananna groove shafts
Holley SD intake
Holley 850 DP
1 7/8 headers/ 2 1/2 pipe / with H pipe (may go 3")
MP Ignition
3.91 gears
Windage Tray

Been told I do and been told I don't.
Please tell me the arguments either way!!
Thnx Chuck!!!

Hi volume oil pump was made to pump more oil through hihger clearances, to restore oil pressure in worn out engines.

So no, you don't need it on your fresh motor, but that just my .02

That makes sense. The advice I got was just that "advice" but no explanation.
I am having the machine shop turn everything to a .002-.003 oil clearance.
Thnx !!

I think with .003 clearance and full groove mains, I'd use the hv pump.

Fully grooved mains - NO. The HV pump wouldn't hurt anything. Or use the HV spring in the standard pump to bump the pressure up a tad.

Read what CaptainKosmos said in a thread I started a while back.

Some info about oil pumps in general. An oil pump is a source of flow not pressure. Pressure is the cause of restriction in the fluid flow, ie you cannot have pressure if the flow isn't restricted somehow. In sense of my education (Msc in hydraulics) the hp pump in street use is pretty much nonsense atleast when referred to hot idle conditions. The pressure you have at hot idle (and in all motor operation) comes from the bearing clearances, oil passages etc. as Moper stated. Idle pressure will not rise with the HP pump because the normal idle pressure should be lower than the bypass valve crackling pressure. In some cases at hot idle the hp pump might infact raise the pressure shown in gauge but in that case, there must be some serious restrictions in the oil passages, between the pump and the gauge sensor.

So in general, the only way to raise hot idle pressure is to add more flowrate to the system which leads into hv pump. This is based on the assumption that one is using normal oil and the bypass valve isn't already open at idle.





The aproximate power needed for oil pump to run when losses are neglected is the pressure times the flowrate. If someone want's to calculate the power needed in kW the formula would be pressure (in bars) times flow rate (in liter/minute) divided by 600. So this leads to the fact that hv pump takes 25% more power from the pump shaft than stock oil pump, if the bypass valve is set at the same pressure. The equation is proportional so if you increase the maximum pressure by 20% the maximum power needed to operate the pump goes up also for 20%. For the amount of power taken, the hv pump is worse because it takes always more power than normal pump. As opposed, the hp pump takes only more power than normal pump, when the pressure level is higher than the maximum level in normal pump.

I'm not going to take any part in the discussion of what kind of pressure levels are needed for different kinds of rpms because I have no experience in that field.

You can read the whole thread here.

http://www.cuda-challenger.com/cc/index.php?topic=54050.0

HV not needed. I have 2000 1/4 mile runs on a simular combo with no problems ever. Oil pressure is 18 lbs hot idle(800 RPM), and 59 lbs hot driving. Had it apart at 1500 runs and bearings were great. Back together with the same bearings. 5500 RPM max.

I always ran the full Groove mains. More space for oil around the crank the better when heated up or running hard. Never spun any mains on my race cars. Ran the same clearences you are looking for. Always ran HV pumps but also always ran a deep pan and a windage tray. Same theory for me more oil was better for engine especially on the track when you leave hard and let out so hard and all the oil on a stock pan sloshes to the front and rear of the stock 5 qt pan. I later went to the Moroso pans with external 1 inch lines and their pump. (I am not implying you need this)

Thnx for that info and taking the time to reply. Interesting!!
Chuck

Thnx all!! I think I will go with a standard pump and normal bearings. I have no intention to race or be winding it up to 7000 RPM's
Chuck

I think you've made the right decision.

No on the hv pump and no more than a 3/4 groove. Good reading here. Link to Clevite bearing catalog. Go to page 12.

http://www.engineparts.com/publications/EB-10-07.pdf