Oil pump upgrade

I fitted one to the silver car i forged (i also have one ready to go into my car) when i was building the engine, before the crank went in and also that the front main bearing cap was still not fitted.
The pump complete was bolted to the block but not torqued, just enough to stop it moving.
I then put the sump on and it sat flat, i secured the sump with a couple of bolts, there is enough room to get your hand in through the front to feel how much clearance there was between the pump and the webs, this one didn't need any cutting.

 

Any before and after oil pressure readings?

 

Could this just be fitted then with no mods was thinking of changing my oil pump anyway

 

You might have to trim a bit off of the webs in the sump, i didn't have to on the 265 engine i forged, but someone else had to

 

No

But i will probably will fit a sandwich plate to mine,(with sensors) so i will let you know.

 

Any further update on pressures with this pump? Keen to get this into my next build if its worth doing!

 

Sorry for spoilering, but nobody needs a bigger oil pump. Every oil pump makes much more pressure as any engine needs and has to be bypassed before the filter is prone to collapse. The principle of an gear pump is that it provides pressure in proportion to the revolution it does. 1000 revs with 10 L/min means 2000 revs with 20 L/min and 6000 rpm with 3 times, 60 L. Even a turbocharged Megane engine will never need 60 L/min, so the bypass has to limit the flow even at let say 4000 rpm to avoid oil pressures too big. The bypassed oil is very hot and very frothy and is bypasses directly back to the entrance of the pump, and exactly this frothy oil will be sucked again whats very critical. This conditions are very dangerous considering cavitation issues because of imploding steam bubbles and should definitly to be avoided. If you encrease the capacity of your oil pump, these conditions will be more critical than before. Big upgrade pumps are most likely to make money, not to improve you engine. More oil pressure doesn´t improve the lubrication of your engine, the load capacity of your bearings is determined by the bearing itself, correct clearance, it builds up it´s internal pressure way more than the oil pressure tells you. The only reason of the big oil pump capacity is to provide an sufficient oil pressure when the engine is hot idling. Now the oil pump speed is very low and the pressure might be too low if the pump ist too small. But at higher revs, 99% of all pumps are too big and has to be bypassed to limit the theoretical possible pressure. I´m currently building a racing engine for my classic Alpine A 110 and I use the Megane oil pump but - i made it much smaller, i reduced the gear width from 21,5 to 15 mm to avoid the problems I just talked about. I would reduce it even to 13 mm, but then the contact area of the shrinked shaft will be to small and might slip. I do race engine developments since 40 years - leave your oil pump in stock condition. If there are really issues what are strange - first look for them. My advice !

Udo

 

Pressure and flow are depending on each other. If the internal leakage of an engine is big ( bearing clearences encreased by rebuild or worn out) the pressure will drop with the same volume pump. Btw: Why would you switch to a Diesel filter ? A Diesel has supposedly much bigger piston oil jets, that´s probably the reason for the bigger pump. The piston jets needs usually 1/3 of all the oil pump capacity. Mostly the Diesel pistons have cooling channels inside the piston crown, completely another design as the MRS. If the oil pressure in higher revs drops a little due to the external oil cooler, you can pretension the oil pressure spring inside the oil pump a little more. As I said in my previous post before, bigger volume oil pumps use 1/3 of their capacity to feed the engine and 2/3 to pump the unused oil through the relief valve, completely useless, causing additional temperature, danger of cavitation and foam what will be sucked immediately back to the entrance of the oil pump, causing again cavitation due to the low pressures what are entering the pump. It´s a big intervention into a lubrication system of an engine what you intend to do, nothing of the components are coordinated to work together, the Diesel has completely different requirements, bigger bearings, much more piston cooling oil volume. If the oil ist hot when entering the extra oil cooler on your MRS, its so low viscosity that it makes almost no difference if with or without oil cooler. You don´t need a bigger pump. But it´s your decision, only a well-intentioned advice !