External Oil Pump

racermr2

New member
STL rules state that only wet sump oiling systems are allowed. However, are external oil pumps allowed versus the stock pump as long as the oiling system uses a stock wet sump pan, no external reservoir, and there is only one oil pump?
 
An interesting question...I'd suggest "no". ST follows the "IIDSYCTYC" model, and 9.1.4.G.13 states, "The OEM oil pump may be modified, or replaced with an OEM-style oil pump."

If the regs said "oil pumps are free" you could get away with it, but not with that.

Just curious, why would you want to do that?

GA
 
Just guessing, but he could have an oil pump gerotor in a front cover? Thus there may be no way to replace the "oe" pump as it's part of the front cover, and an external pump plumbed in to replace might be the only option to increase pump volume.
 
Seems plausible. Mine's that way in the Honda, though there are aftermarket pumps that have higher volumes (thicker rotors).

But, unfortunately, I do not see where putting in an external pump is compliant to the STL regs. That's a personal opinion, BTW, not an official interpretation of the regs (see sig). - GA
 
Greg Amy: My reasoning for the external oil pump is that the stock pump does not have factory or aftermarket gears available that will increase volume and pressure. While there are means to adjust the pressure nothing available for volume increase unless an external single/two stage pump is allowed. This is for a mid engine Toyota.
 
Greg Amy: My reasoning for the external oil pump is that the stock pump does not have factory or aftermarket gears available that will increase volume and pressure. While there are means to adjust the pressure nothing available for volume increase unless an external single/two stage pump is allowed. This is for a mid engine Toyota.

Rudy, as you should already know, on our ITB MR2s we run a stock update (15100-19036 PN, which is the later PN replacing ...35 number. earlier pumps were 15100-19025 replaced by ...26 and are superseded by 35/36 units) which uses the round-tooth style rotor rather than the sharp tooth and bridge style the 4AGE came with before the update. this pump maintains the same pressure but moves a LOT more volume AND is less prone to failure due to reduction in sharp edge stress risers. in our IT cars we run through -12AN hose to a front-mounted LARGE oil cooler (19-34 row, depending on car) and back to a remote filter (I use WIX 51515R which take a qt of oil to fill) and then back to the OEM filter inlet via adapter plate (get the Earls or CM mounts, the rest have a ford-sized O-Ring and will leak) via -10AN hose, teeing to an Accusump on the way.

no shim in the pump (not legal in IT) I see 60+ PSIG in the block after all of that. we spin upwards of 9k RPM when needed, usually only to ~8200. you don't need an aftermarket pump.

the updated pumps are marked on the exterior "AISIN 2" older pumps just "AISIN"

BTW - this pump is the same PN used in the 20V (pre-hydraulic tensioner) and 2UZ-FE V8.
 
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