Jim85IROC

iTrader: (6)

I just got my Melling 10296 high volume pump from Summit yesterday, and before I put it on the motor I'm contemplating porting it. I've ported a couple stock oil pumps, and everybody seems to favor porting the stock ones, but I never see anybody mention porting the Melling pumps. Based on what the Melling looks like inside, it's nicer than the stock casting, but looks like it could still benefit from some cleanup on the outlet side.

KCS

iTrader: (20)

I like to radius all the sharp edges in the inlet and outlet. That's basically the extent of porting these pumps, whether it be stock or aftermarket.

Carshopinc.com

iTrader: (5)

I agree with KCS , we have never seen flow #s increase when porting the pumps.

Be careful when disassembling a pump unbolted from the engine. Housing distortion
is not uncommon ... We have known of customers who clamped them in vices or
C clamped to bench tops, causing rotors to bind in the housing.

lsxnation

iTrader: (2)

post pics of the comparison

Jim85IROC

iTrader: (6)

Here you go.

First pic shows the brand new 2011 Mexican made OEM pump on top, the 97 pump in the middle and the 03 pump on bottom:


Back side, same order:


all 3 pumps taken apart:


Outlet of the '97 pump:


Outlet of the 2011 pump. Notice the terrible machining in the outlet, and the rough casting:


close-up of the '97 pump after I ported it:


Next are the pics of the melling. In my opinion, at least visually, the melling is a much better made pump. The casting is nicer, and the machine work is much nicer. The outlet looked a lot better, with a much smoother transition from the gear area to the back where it mates to the block.

now here's the melling with the cover off:


Melling with the gears out:


close up of the outlet:


Close up of the inlet area, which is also a little nicer than the stock casting:


My mild port work on the melling:



The melling all buttoned up and ready to go onto my motor:

pairof69s

what did ya pack it with assembly lube? fixing to purchase a melling for my LQ9, wasn't sure what to lube it with, looks like a quality piece by the way

Jim85IROC

iTrader: (6)

I just lightly coated the parts with assemvly lube.

rggbly

iTrader: (22)

so for a cam swap is it necessary to purchase a new oil pump and port it or could you just port your original one?

JPH

iTrader: (2)

I have done a few for good measure. Make sure you take the relief spring out and it's entire assembly and clean that up and oil it before reinstaling it.

Jim85IROC

iTrader: (6)

In my opinion, the stock one should be just fine as long as you take it apart, fully clean and inspect it, and re-assemble it properly. This is of course assuming that you had good oil pressure prior to the cam swap. Once you get inside of these things and see how few parts there are, you start to realize that there really isn't anything that can go wrong with them, except for potential issues with the bypass spring weakening, or the bypass plunger sticking open.