|03-03-2011 02:44 PM|
|cool rockin daddy||
Do not listen to one word from the poster "Mouse Fink". This board has gone round and round with him about oil pumps. His theories are, shall we say, "unique". BOBCRMAN and COBALT are very well respected and their knowledge is second to none. Follow their advice and you will not go wrong. I do not post this to start a p***ing match, I just don't want you to get confused.
|03-03-2011 02:36 PM|
Oil cavatation cauised by a 3/4" pick up is a new one. The following is where that theory came from.
There will be oil cavataion beneath the screen if the pick up screen is less than .375" from the floor of the oil pan. That happens when a HV oil pump is installed in a engine with a stock depth oil pan. High volume oil pumps have 0.300" longer spur gears, a longer and thicker housing, 3/4" pick up tube and a thicker bottom plate. That makes those pumps 0.587" longer than a stock oil pump that has a 5/8" tube. If you only have 0.375" to 0.500" clearance between the screen and bottom of the pan with a stock oil pump, then subtract .587" for a longer HV pump, as you can see, the clearance becomes critical. Optimum screen to pan clearance is between .375" and .500". The easiest way to measure is with a carpenter's square from the block pan rail to the bottom of the screen after the pump is installed finger tight. Then compare that measurment against the pan depth from the pan rail to the bottom of the sump.
There are dozens of different styles and depth oil pump pick up screens available from Moroso and Milodon but buying those pick ups through trial and error can get expensive. After purchasing four different Moroso pick up screen assemblies, I finally gave up on aftermarket pickup assemblies. I shortened a stock 3/4" pick up tube 0.500" and it fit the longer Melling Select 10552 oil pump and stock oil pan with 0.450" clearance.
This is why Moroso offers HV oil pumps, pump pick up screen assemblies and a special oil pan in a kit which is supposed to eliminate most of the guess work.
|03-03-2011 01:51 PM|
|03-03-2011 01:35 PM|
oil pump shaft length
Thats it no filing or machinig just an ARP shaft,, thats what what I'm running in my 360 sbc right now. Of course I'll by a new one but is that all clean it and install,please tell thats it cobalt.
|02-09-2011 09:44 PM|
Oil Pump shaft: 350 main = Stock shaft (.481” OD)
400 main = Stock shaft (.425”OD)
I personally have always used an ARP shaft, it has plenty of clearance.
|02-09-2011 08:55 PM|
oil pumps and pans
ADAM 65 you mentioned a necked down shaft I called jegs and summit and Moroso and they all said its the same shaft for 350 or 400 sbc what make or model shaft are you reffering to specifically.Thanks again for the tip but I cant locate what you wrote about
|01-22-2011 08:31 AM|
oil pumps & pans
Thank you for that usefull tip.
|01-21-2011 09:30 AM|
|Adam65||Since you have a 400, make sure that your oil pump driveshaft is the necked down one that is specific for a 400. (Due to the 2.65 mains, compared to the 2.45 mains on all other small block chevy's). A 400 driveshaft will work in any sbc, but if you use a non-400 driveshaft in a 400, it will rub where it goes through the hole in the main cap & block.|
|01-21-2011 08:58 AM|
oil pan and pump
Are there any 406 chevy owners with full hydraulic roller motors who can recommend a decent set up for daily drivers with 500ftlbs motors that will see 6200rpm max,5 ,6,7,quart,moroso, milodon,jegs again like all of you who cherish your hard work and money involved, i just dont want a catastrophic failure,i'm an assembler not a builder and would like to hear from someone who has done this more than twice,once for the build and once for the grenading of the motor,I know I sound like a broken record but successful execution relys on precise planning. Thank ou all again for your time.
|01-21-2011 05:56 AM|
|Adam65||If you're looking in Jegs, 689 prefix is just Jegs' number to signify a Melling product. On my 80-85 350 I just did, I used a Milodon street/stip pan #30901, with a Melling 10552 pump (which is stock pressure & 10% over stock volume). The only reason I went with 10% over volume, is I have solid lifters with the EDM holes in the face-otherwise would have went stock. The pickup depth to pan clearance was 3/8 or 7/16"-didn't have to mess with modifying anything.|
|01-20-2011 08:59 PM|
Oil pan and pump type
Thanks guys Adam the melling series you were talking about do you have any model numbers for them such as the "regular meling 689m55" ,then there is a line called high performance oil pumps with the code 68910555,both are same volume.
Moroso has aline to fit the pan Iam eyeing with the pick up welded on ,then they also have a line of blueprinted oil pumps as well, must it be so difficult.
As for pans does any one think windage tray and scraper or not ,baffling is a given regardless,anyone else
|01-20-2011 12:10 PM|
|BOBCRMAN@aol.com||You are correct. I am so used to using my old stock stuff (I bought all the old pumps my warehouse had). I had forgotten to mention the change. Actually I have two broken newer ones on "The wall of shame" (broken reminders of the past)|
|01-20-2011 12:02 PM|
|Adam65||The m55 pumps are a weaker, thinner casting than they used to be about 5 years ago-they are notorious for breaking off. The Melling Select line of pumps are actually thickness of the old M55 pump body-with the addition that the pickups can now be bolted on.|
|01-20-2011 11:54 AM|
|BOBCRMAN@aol.com||The most you need is an M55A Melling pump. AVOID the 3/4 inlet pump. Large inlet pumps have caused many problems for Chevy owners.. These pumps allow air cavitation on cold startup. Starving the front crank journals for oil.|
|01-20-2011 11:33 AM|
oil pump & type
I'm asking should I go stock or more for a daily driver 2-3 times a month at the track and 6200 max rpm, which it will see at least 3 times a day, with a magnum roller set up cam 230@.50 lift .560 single pattern,and scorpion or harland sharp 1.5 rller rockers have not decided that one yet. any help or guidance guysI want to do it right the 1st time. Thanks
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