Quote:
Originally Posted by ETM_Shaman
I've looked at and measured the lubrication system in this engine so much that I know it by heart, but that diagram helps a lot and I'm gonna populate it a little better:
As you can see the way from the stock pressure switch location to the main gallery is not that long but it's VERY convoluted with many sharp turns (all the drillings that meet have sharp round edges inside). The gallery that goes from the pump to the block is the thinnest part of the whole crank feed system. Also notice *10 is not straight like they picture it but tapered from the outside to the center (probably from the use of tapered pins for casting). *4 is not a return line but the gallery that takes oil to the no 1. chain tensioner, it only exists for that.
@ Ultramaroon I did validate my gauges and as you have noticed, the pressure drop changes a lot with RPMs (because pressure drop in a gallery is tied to flow, with all other variables keeping the same). With my measuring setup at idle, both gauges read almost the same and the difference increased gradually as I increased the RPMs (which also validates the sensors readings)
I see you get about 10 psi drop (~ 0.7 bar) at 6,000 RPMs. I'd be curious to know what crank and rod clearances your engine has, is it stock?.
I figure the reason I see more pressure drop is from using looser crank and rod clearances than a stock engine (although barely out of the stock range). |
Thanks for updating that chart. Makes way more sense.
I wouldn't put much faith in my absolute numbers but they're ok for comparative analysis. Mine is bone stock with a tad over 50 Kmi now. I am super gentle when it's cold but otherwise am not afraid of beating the piss out of it. I can run sustained high RPM using 0w20 without pressure drop because I have a massive oil cooler. Flow is manually controlled with a diverter valve to keep things in balance while I daily. Max pressure drops like a rock above 90*C and although I'm sure I'm being paranoid, I feel good about my setup. UOA helps to confirm that I'm doing it right.
I forgot about the deliberate extra clearance at your main and rod journals. Taking that into account, our respective numbers jive nicely! Note your comment in bold - I gotcha. Your point about the twisted path is well noted. I feel like I've learned quite a bit this past couple days.
