Oil pressure drop is sweeping right-handers...

From Bash Hat's 4.0 thread: " I�m all about the spirited wine country canyon drives but I�ll still see the oil pressure drop on fast right handers." So yeah, this has been discussed ad-nauseum regarding the M96 both here and elsewhere but I thought I'd just add my own little twist. I'll preface this by saying; I'm not talking about track usage here - what I've observed has been strictly on the street, but should translate to the track as well albeit with bigger #'s. The main thing I've noticed is that the oil pressure really only drops precipitously if you let the rev's drop as well. Obviously, when you're entering a turn, it's natural to let off the gas and sort of coast into the turn - this is when the oil pressure really starts to dive - perhaps maybe even dangerously low if you punch the gas coming back out of the turn. I've found that downshifting going into the turn and keeping the rev's @ or over 3k (in 3rd gear - approx. 50 -55 on a exit ramp for example) the oil pressure will dip slightly, but remain fairly constant... Comments/Opinions?

I think you are correct. Logic says that since the oil pump is driven off the engine, the higher the RPM's the more oil is being pumped through the engine. After I get warmed up, I typically stay in the 2500-3500 range, and I downshift when approaching a turn or corner, never really dropping below 2000 except when coming to a stop. I don't row the gears down when stopping (downshifting)...that to me is not useful. I think it is good to use the power of the engine when accelerating, so I hardly ever get out of third gear running around town.

That might well be so. My issue is that even above 3-4k rpm the pressure drops up to 2.5bar (from around 4bar down to 1.5 or 2). And that is with regular spirited driving, not going at it like a madman. Ever since changing the pressure sensor/sender I�ve been able to observe that. Before, the pressure would just stay high. It really is a bit of a killjoy, as my eyes go down to the pressure gauge midturn and I hesitate to enter turns with spirit.

I can assure you that on the track, you can be full throttle coming out of a turn and pressure can be very low. You are correct though, oil pressure under less throttle will be less.

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Sure - the higher the RPMs, the faster the pumps are turning, and therefore, moving more oil. But if temps and revs are kept very high - let�s say 4,500 and above - it�s more likely there will be pressure drops because the volume of oil being moved around the engine is also higher. And aeration will probably be higher as a result, so it�s a double-edged sword, IMO. It seems like I�d rather have a mix of air and oil at 2.5 bar at 4,500 RPMs than larger air pockets with 0.2 bar at 1,500 RPM, but then I worry about how many revolutions are taking place during starvation... I dunno, it�s bad either way, and I try to avoid it, as I can envision that one way or another, the engine is eating itself, however fast or slow that happens.

" My issue is that even above 3-4k rpm the pressure drops up to 2.5bar (from around 4bar down to 1.5 or 2)." ^^^ So the question becomes: at 3-4k rpm's is 2 bar dangerously low? "I can assure you that on the track, you can be full throttle coming out of a turn and pressure can be very low." ^^^ I believe you! As stated above, is 2 bar (or even 1.5 at 3-4k rpm's) dangerously low? If not, what is? What have people experienced when spinning a main bearing for instance?

2nd gear, WOT, 4K RPM, LN Deep Sump & Baffle, XP9 Oil 1/2 way full dip stick, 45 DEG ambient temps early in session.... 2 bar mid right corner as shown on stock gauge. Will probably be worse when I get my logging setup in place.

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Well if it didn't blow up/spin a bearing under those conditions, I/we should be fine on the offramp (even without the deepsump/baffle)!

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Yeah, kinda, pretty much. If the gauge is showing 2 bar for a second, it could actually be 0 bar for part of that time because the gauge is coming down from being up there. Pressure bleeds off over time and the gauge has latency. Will the engine blow up? Not right away, not even soon. But it�s going to have metal to metal contact, likely on the piston rod bearing, which will cause excess heat or scraping of metal, removing some material, which increase the tolerances there. Over time, do this often enough, repeatedly, and the bearing will be shot, potentially causing a rod cap, rod bolt, or rod to break apart.

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What�s interesting is that I didn�t change a thing aside from oil and a new sensor. Drove it hard the 45k miles or so before, never had a drop (show up on the gage), no issues with the engine either. So, I�m left driving less animated, especially on uphill right turns.

I've solved this, read here: https://rennlist.com/forums/996-foru...n-corners.html Your scavenge pumps are probably bad, so the oil level in the sump is too low for the G's your pulling in the corners. Also, fill the oil completely full (check oil level according to manual, hot and level).

This helps.