critter

iTrader: (9)

Anyone have any idea why my $130 Melling High Volume Oil Pump has the same thickness rotor assembly as the much less expensive GM pump it is replacing?

jtl12419

iTrader: (13)

Yes, but its advertised to deliver 18% more flow!! (Not 10, not 20, but 18%)

Honestly, I don't know, since I ordered one too, but not here yet.

Surprisingly, Lingenfelter sells a "stock, heavy duty GM" pump which they "use on their cars" for twice the GM price. And Katech and SDPC both sell a "blueprinted, balanced, and ported" stock pump which suspiciously looks like the same one for the $150. Other venders are also selling ported stock pumps for the same price as the Melling.

It might be smoke. We should get Mellings number and call them to ask how the quoted 18% flow increase was measured. I have a sneeky suspicion that they use 18% as an average number across all their oil pump lines. Where is this pump made BTW?

Let me know if you find out. Caveat Emptor in the auto products industry!

critter

iTrader: (9)

So maybe the GM pump is that expensive one. Came with the short block. I don't have a stocker to measure. The GM is 0.508" and the Melling is 0.500". Can anyone measure a stocker?

I googled for Melling and didn't find anything, so no phone number that way.

The pump is pretty rough inside - it is a sand casting instead of die casting like the GM pump. I removed a rather nasty step at the inlet and smoothed the outlet. Don't know if it helps, but can't hurt

SteveDoten@ARH

talked to the Melling rep at the PRI show, the pump has a cast iron front cover and revised spring rate to increase flow/pressure, doesn't really answer your question

seems most just add a washer to a new LS6 pump and do some porting