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420A high volume oil pump

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not tell you are over 10k rpm

if you get too much oil pressure and/or volume, the oil travels to fast and will not cool the bearing surfaces or bearings, there will not be the heat transfer.

plus it will take more HP to spin the pump, thus making you slower.

general rule of thumb, 20 psi at warm idle, and 10 psi per 1000 rpm to appox 50-60 psi and you should be good for 9000 rpm

go look at a nascar cup car, spinning 9200 rpm in the stright.. on the in car cam you will see about 60psi.

Now ask yourself.... are you near that level of performance?
 
someone correct me if I am wrong, but I believe that many 420 members have had extremely bad luck with mellings high volume oil pumps, much of it could because of what BogusSVO said, and not many 420a members are pushing that high of RPMs
 
Yes some people have bad things with them, But when you go to the dealer the milling is what they sell you. I dont think you can buy the old oem anywhere.
Alright, wait one cotton picking minute ;)

There is a difference between the Melling OEM pump and the Melling high volume pump. You can read through these for some background info;

www.neons.org • View topic - STD oem oil pump vs Melling High volume pump

www.neons.org • View topic - OEM oil pump nonexistent anymore. WTF!

Bottom line is that our OEM pumps are all you really need. I have seen a pretty good failure rate with Melling oil pumps. Its not like the majority of them are bad, but I personally know of too many failures for not enough payoff (both 4g63 and 420a).

I couldn't find the thread in neons.org, but somewhere in there they took apart an "OEM" Melling and a "High Volume" Melling to see there were some differences in the drive gear. The theory is that the design of the difference is not as good as the design of the original and that's where the problem lies.

Is it worth it to get a Melling and stand the chance of a seized motor? Me. I'll pass.

In the FWIW department, my favorite oil pump to buy is a "known good" low mileage (as in under or around 1000 miles) OEM pump. Because that one has been tested on an engine and I know in those miles, if there was a problem, it would appear. I would choose that over a brand new one (and have).

And I have raced on "known good" high mileage pumps with NEVER a failure! (with 8200 to 8700 redlines).

MB
 
If your interested DCR sells a a billet gear for replacement of the standard oil pump ring gear. I for one wish I would have gone with it instead of a Melling High Volume pump....case and point.......
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And that was a brand new Melling High Volume oil pump with maybe 10k on it. Broke on the dyno :(
 

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@Slo2gen.. did you ever send that pump back to melling? They may find it usefull in correcting the problem.
 
It is the same. Milling is now the factory replacement.

I know milling is a factory replacement but when do you need a high volume over a standard volume??

Melling.

not tell you are over 10k rpm

if you get too much oil pressure and/or volume, the oil travels to fast and will not cool the bearing surfaces or bearings, there will not be the heat transfer.

plus it will take more HP to spin the pump, thus making you slower.

general rule of thumb, 20 psi at warm idle, and 10 psi per 1000 rpm to appox 50-60 psi and you should be good for 9000 rpm

go look at a nascar cup car, spinning 9200 rpm in the stright.. on the in car cam you will see about 60psi.

Now ask yourself.... are you near that level of performance?

Keep in mind that pressure and volume are not the same things. Same reason why Talking about PSI on a turbo is not relevant when discussing power output (unless comparing turbos in the same family or similar compressor design/map).
 
@Slo2gen.. did you ever send that pump back to melling? They may find it usefull in correcting the problem.

Yes I did contact them and they said to send the pump back to them but all they would be able to do would be (AT BEST) give me another oil pump. You find out fast, if you haven't allready, there are not too many companies that will warranty other stuff that fails due to a product failing. That would be like me running an egt probe in the manifold and the tip breaking and expecting the manufacture to buy a new turbo for me. Just not gonna happen. After that I bought a brand new OEM pump and pulled it out of the "Dodge" box and the pump had M190 stamped on it. Apparently Melling has been making the OEM pumps all along they just added a pentastar in the casting(which is not there anymore).

Bullet, yeah I was laughing, kinda. LOL but I have since moved on to bigger and better things and sold Tim the motor so technically its still going strong!
 
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