LSX oil pumps 101

[Sabre002]

I have gone through so many oil pumps and heard to much wrong information in the past it’s not even funny. 
This is the LS1 oil pump I ported and put in Roman’s FD.
This is a very good porting how too. 
http://www.andersonperformance.net/LSx_Oil_Pump_Porting_v1.2.pdf   
Stock trim

After I got done with the outlet

This is the pickup after


Now that pump above made 35PSI hot idle with 5W-30 in it for street use.  As far as I know that engine is with its new owner and running fine. 

Here is the pumps we had show cased today. 
From left to right.  LS6, LSA, LS3

Here are the springs we had on hand between a friend and I.   For a side note for later the last spring on the right is what was pulled out of the CNC ported pump from Katech.

LS6

LS3/5.3 PT# 12586665 this is the standard LSX pump from GM for now.  I find it in most trucks I take apart that have AFM or not. 

LSA/ L99 (VVT is the key) PT# 12612289

Now if you notice the LS6 and the LS3 pump are for the most part the same.  The casting is a little new for the LS3 but it’s the same size pump in every way.  I measured the thickness of the gears on all, the depth of the oil spring plug, Also that the spring in the LS6 and the LS3 they are different colors but are the same spring. 

Here is where it gets interesting. 

Here is a ported LS6/LS3 note above oil pump. 
http://store.katechengines.com/gen-34-oil-pump-p5.aspx
Here is a ported 23% high volume oil pump.  (LSA/L99)
http://store.katechengines.com/high-capacity-gen-34-oil-pump-p272.aspx
Here is what you will get, the ported inlet and that last spring in the pic of springs above. 


Here are the stock inlets from the two pumps I got
LS3

LSA/L99



From day one I have seen ported pumps be in the high 100’s and I have took apart to many to count.  The one thing I notice is most doesn’t touch the outlet.  When the outlet porting use to be the norm.  Hell pick up the HP LS1 book wrote buy the guys from MTI and GMHTP look for yourself. 


Here is the millings pump that failed

[WannaBeFast]

Professor I have a question!

What can you tell us about the stock pump on a 2004 5.3L Silverado engine?

Thank you.

[Sabre002]

being 04 that would be still a GEN III engine so I do not see why it would be any different from a LS1/LS6 pump in 2004.  I can pull the part number tomorrow and check tomorrow. 


For the record the Millings cast iron pumps, have eating the cases out with the gears.  they must be pot metal or something I dont know whats going on with them I will take a pic of that tomorrow.

[Speedfab]

Professor I have a question!

What can you tell us about the stock pump on a 2004 5.3L Silverado engine?

Thank you.

I can tell you that the 2004 Silverado SS 4.8 is the baddest of the bad, period.

[southside427]

has anyone been shimming the stock springs in addition to the porting?or would you maybe go by what the oil press. was prior to disassembly?

[Sabre002]

.115 on the stock LS6 pump was about 12 PSI.  There are so many springs out now I would get one that does what you want.

[zbrown]

good thread man, reps

[WannaBeFast]

Professor I don't understand!

I just want to know if it's good/ bad? Necessary to upgrade for boosted applications.

Thank you Professor Sabre.

PS: Doctor Speedfab I'll take an answer from you too haaa lol.   

[Sabre002]

If you are going to be putting a load that a boost engine required on it I would make sure first off that the oil clearances are correct.  As for the pump, I would suggest ported and change the spring for more flow and pressure.  Even if you just did that to the one you got.  Now all this is bearing an inspection of the pump you have to see if its not worn on the case sides. 

If you just want to buy something I would get the L99/LSA pump for it and roll.  I was told GM parts direct was 66 bucks. 

[WannaBeFast]

Great info. This class is awesome.

[Sabre002]

Update for the failed pump

[perf0rmance]

Guess I failed... So which one is recommended to run for a bolt-on ls1?
I actually have an ls6 with 241 heads.