SB Chevy zero cost oil pump power mods

[MAP]

Greetings,

I inadvertently posted the following question in the wrong thread. Now that I know that it goes here, it is:

Does anyone recall the gist of Dusty's article? I'm going through a Mellings M-55A pump (built in 2000) and would be thankful to be able to apply any of the recommendations in that article while I've got the pump apart.

Of course, any additional pointers would be welcome too.

Thanks,
Mark

[Pinhead]

He basically took the pump apart and radiused the flow path of the oil right behind where the gears meet eachother.

If someone had a picture of the inside of the pump I could "recreate" the original picture with MSPaint...

[MAP]

Hi Pinhead,

Thanks very much. Makes sense - "port" the flow path of the oil as if one were porting heads for airflow. As j_cizzo said, however, the entire path is full of kinks and abrupt turns. One wonders if radiusing turns at or near the oil pump alone, can reduce total flow resistance very much.

Best,
Mark

[Pinhead]

Hi Pinhead,

Thanks very much. Makes sense - "port" the flow path of the oil as if one were porting heads for airflow. As j_cizzo said, however, the entire path is full of kinks and abrupt turns. One wonders if radiusing turns at or near the oil pump alone, can reduce total flow resistance very much.

Best,
Mark

The resistance inside the pump wasn't only caused by the "backpressure" from the oil trying to flow through the passages...

He also "extended" the "port" area to a little bit further between the gears which is where a lot of the pressure comes from. Normally, a bit of the oil is squeezed between the gears, and has nowhere to go other than to go all the way around. The small "port" extension alleviated that pressure. I really wish I could find a picture of the inside of the pump so I could try to better explain what I'm trying to say.

[MAP]

Thanks,

OK - from the cylindrical ID of the pump exit, along a line that bisects one that would pass through the two gear centerlines at their bases, runs an auxiliary channel up to a point presumably not far from the bisection point. The channel has a cross-sectional area TBD, or alternatively width TBD and depth TBD, and the channel ends at a distance TBD either on the output or input side of the gears, from the bisection point.

Is that about it?

Thanks,
Mark

[j_cizzo]

all the pump mods in world can't solve a system that is generally lacking.

all the pump mods in Dusty's article are to increase idle, and just off idle, oil pressure without costing anything and they definitely work. BUT at the end of the day, when you're REAALLY trying to extract power thru the details, you still need to address the system as a whole.

Dusty reported some 3-5psi increase in idle oil pressure just from doing his mods and i absolutely believe it! i saw the pics and it all looked pretty wild, but also all within the realms of common sense; ya look at it and it all makes perfect sense. BUT the two problems we're left dealing with: it still doesn't deliver the oil needed at higher RPM on a higher HP engine, and also, while cavitation is greatly reduced, to truly eliminate it, you need to cut those anti-chatter grooves which may be detrimental to low-end oil flow.

all of which will become apparent once the pump starts pushing so much oil that those twists and kinks overwhelm the pump.

best thing to do is have the oil come right out of the filter pad on the block, go to a remote filter and have it returned at one of the two holes on the rear china wall where the pressure sender is usually mounted. you'd have to plug the path leading from the filter pad into the block, and you'd be removing the bypass, but we all change our oil on a regular basis so a plugged filter is not an issue, right?

PLUS if done right, eliminating all those corners and kinks via the system i just briefly outlined would eliminate the need for the bypass. besides, i believe all good filters now adays have bypasses in them anyway.

[j_cizzo]

one thing to be mindful (i don't know if it applies to the M-55A, i just know it applied to the melling pump i bought), you have to make sure that the trough on the rear main cap where the pump attaches to matches to the pump. on mine, i noticed that the trough on the main cap covered part of the discharge hole on the pump, where the oil flows out of the pump into the maincap and then into the block.. make sure that's all matched up and smoothed out (a dremel works perfectly). match it all up, get it to flow properly, and then use a dremel buff ball to polish it and make it nice!

if that's covered up, no amount of work done to the pump will help you and your bearings won't be around too long...

[howieschoon]

J cizzo,
Do you have Smokey Yunick's Power Secrets? If so, check out the bottom of page 115, is this the area/modification you are talking about to bypass all of the bends in the block? I believe that somewhere in that book he mentions a modification similar to the one that you describe, but I am not possitve.
Howard

[comp]

Dusty: What happened to the pictures of how to modify the oil pumps? Are they in an archive or am I doing something wrong that I cannot see them? This was a very good article and wanted to use the process to modify my SBC oil pump. Also the article on flushing the oil system prior to final assembly of an engine is also gone. Where or how does one get access to these articles? Please advise. Thanks.

i agree ???

[j_cizzo]

J cizzo,
Do you have Smokey Yunick's Power Secrets? If so, check out the bottom of page 115, is this the area/modification you are talking about to bypass all of the bends in the block? I believe that somewhere in that book he mentions a modification similar to the one that you describe, but I am not possitve.
Howard

naaah, i don't have smokey's book... i'll have to check it out though!