I"m just curious what kind of oil pump everyone"s running.

 

There was a pretty good discussion last week on this one. I have installed a Melling M77 HV in my freshened up 74 BB. It shows 70 psi when just spinning with the starter. Haven't even fired it yet. From the discussion, I have decided to change back to a standard volume pump. Probably will get a standard volume GM pump. So, if you need a M77HV...let me know.

 

Stock pump for a stock motor.

 

I have installed a Melling M77 HV in my freshened up 74 BB.
.....I have the same in my 77' BB.............Jerrylee///

 

I put a high flow oil pump in a stock 350 once. On start up I pegged the oil pressure gage. Once it warmed up it came down to right around 80 PSI. My biggest concern was blowing off the oil filter at high pressure. I went back to the stock oil pump.
Good Luck, Wally

 

I appericate the offer on the m77 but it won"t fit my not so stock small block.

 

I'm running a big block Melling in my small block.

 

I have been running the stock LT1 pump in my last 3 motors. Same pump for the last ten years. Just had it apart and it still looks like new.

 

I've got a Melling 10550, HV & HP. We'll see how it performs.

 

I can not speak about the situation with the BBC pumps, but
anyone considering replacement of their SBC pump should
be aware that in 2004-2005 there was a change to the SBC
casting. Pumps distributed since then ought to be carefully
evaluated to determine whether they are suitable for your purpose.

There is a lot of reading in the following threads from C4 Tech
The Disasters thread discusses the Melling pumps used by Canton
near the end.

My conclusion is still that there appear to be a light, medium and HD
version of the castings resellers can choose from the manufacturer.

.

 

Does anyone know why my NEW Melling standard volume - M77 pump came with an extra spring & pin lying in the box? There was also a paper notice stating > To rebuild HP Corvette pumps, install blue spring included.

 

On my Melling HV/HP, the extra spring was included for increasing the pump to HP. I disregarded it and have used standard pressure for my application. Lots of discussion why of hi pressure is needed. On my build, I spend time on clearancing everything to ensure sufficient oil return and decided that a high volume pump was in order. I'm too dump to know why a hi pressure pump is needed for my mild street/strip application is needed.

 

Well this turned into a real nightmare!!!!!!!!!!!!!!!!!!

 

I'm running the GM factory oil pump. The one listed for the LS-7/ZL-1. Works great. Runs around 60PSI when it's hot.

 

How do you mean?

By my reckoning, the current choices for SBC use in a performance
application are fairly clear-cut.

But I don't know the particulars about your not so stock small block
or the primary application it is used for. So perhaps your requirements
call for other solutions.

.

 

I just don"t understand what pump i need or don"t need ! Can i run a melling m55a as long as it doesent have a warning enclosed in the box? I went and looked at a melling m55 it had the warning with it. they didn"t have a m55a there but said come back in a hour and they would have it. thanks

 

Guys...guys...guys. Your Melling M-55HV pump comes with two springs. The pink spring (usually installed) is the high volume pressure regulating valve spring. The plain colored (included in box with pin) is the standard pressure spring. YOU DON'T NEED TO BUY A NEW PUMP IF STANDARD PRESSURE IS DESIRED!!! It's very easy to swap the springs, and if yours didn't come with that plain standard pressure spring...you can get one for a few bucks.
IMHO the Melling is a tight tollerance heavy duty well made pump.
Eddie

 

It would be easier to have folks read throught the other threads but
there is a lot of material there and it took a while before the haze
began to clear. Here is a synopsis.

Look at the pump leg. How wide is the casting lip where it has been
cut by the facing operation to the mounting boss? (The M55 Std Vol
pump is very narrow here, the M55HV high vol pump is wider, the
M-Select series pumps are widest.)



Is the horizontal portion of the web from the leg to the boss for the
driven shaft in the body stepped? (I've marked the image with the
Moroso p/n but I hold Melling responsible for the issue.)



If so, this is the lightest of the three castings that I am aware of
and I do not think your supplier will be able to produce an M55?
with a heavier casting.

If you feel that a std vol/std pressure pump like the M55 is appropriate
then the heavy duty equivalent is the M-Select 10553. Here is a
clip from another thread with a partial list of the M-Select pumps:
Here is a link to a Melling catalog - M-Select pumps appear on page 3

Edzred72, Melling appears to make a large percentage of the
SBC pumps on the market. Pumps from other vendors appear
to be re-boxed versions of the Melling units.

The issue is that there has been a change in the castings
Mellings produces for the pumps, specifically that they
have reduced the amount of material in the leg that mounts
the body to the main cap.

The difference in price between the revised pump and the
M-Select pump is trivial - especially when you consider
that the M-Select includes a HD drive shaft. The M-Select
line consists of a variety of pumps from STD Pressure/STD
Volume 5/8" inlet units up to Hi Pressure/+25% Volume pumps
with 3/4" bolt-on inlets.

For the sake of saving $10-$20 dollars, why buy a pump that
has been built in a fashion that permits this to occur?



.

 

(Edit: this post is a response to one by Little Mouse which
has since been removed)

There is also the M-Select 10552C which has anti-cavitation
grooves in addition to the features you mentioned.

A consideration to keep in mind is how shallow the oil pan is.

Features like the extended shafts, 3/4" inlet and longer gears
for the high volume versions all extend the distance the pump
hangs down from the mounting point on the the rear main cap.

The 7" RR pans on a C4 appear to reduce the pump choices.
I believe the C3 pans tend to be deeper so this may not be
as much of a factor.

.

 

You have a PM