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So, I think there are a few points to clarify here. First, to answer rp's question, on heavy accel, my Gs fluctuate between 0.75 and 1.0 all the way through first gear. I don't know what a stock car does, but there's a notable drop in oil pressure on the logs.

Second, we're talking about mitigating a decrease in oil pressure on a vehicle with bolt-ons or less. If we're putting enough money into a build that requires pulling the engine, then sure, let's put a race pan in it.

For those of us who plan to road course the car, I have no idea what oiling system/PCV issues they're going to have, but they'll probably be different from those that plague the S2000 owners who load up their valve cover with oil.

For those of us who just use the Q for occasional test 'n' tune nights and stoplight battles, the aforementioned oil pressure drop (which is the same thing that happens to modified GT-Rs) can be mitigated with .5-1 qt overfill, with no detectable side effects. It might affect crankcase pressure fluctuations and such, but it isn't enough that the rotating components contact the sump oil, so there's no danger of churning the oil.

I've been running 1qt over in both cars, no issues, and the oil pressure drop in the Q is gone (and I never measured the OEM fill level oil pressure in the GT-R, but I've seen logs from other cars - it was enough for me).

:)
 

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@Loring Does the extra 1/2 quart get you to the top of the dipstick H line? I know I can just pour in the 5.5 Qts (w/filter change) and find out but just curious so I have a baseline to work off of.
 

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I think this might be similar to that "towing" thread.



While the manual says NOT to overfill (section 8-11) my dealership kept overfilling the oil above the H line (this is the 3rd time now), about 1/2 quart if I would throw in an estimate. No issues there really and I'm not concerned about that more than over tightening the drain plug. I'm beginning to think reading isn't their best suit, given that the torque spec is already printed beside it.
 

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I do have a question about the VR30 oil cooling systems. The service manual shows two engine oil coolers, one that is air cooled and one that is water cooled. What determines which oil cooling system is installed?


I believe Red sport/Sport (air-cooled) vs non-sport trims (water-cooled, right where the oil filter is)
 

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So, I think there are a few points to clarify here. First, to answer rp's question, on heavy accel, my Gs fluctuate between 0.75 and 1.0 all the way through first gear. I don't know what a stock car does, but there's a notable drop in oil pressure on the logs.

Second, we're talking about mitigating a decrease in oil pressure on a vehicle with bolt-ons or less. If we're putting enough money into a build that requires pulling the engine, then sure, let's put a race pan in it.

For those of us who plan to road course the car, I have no idea what oiling system/PCV issues they're going to have, but they'll probably be different from those that plague the S2000 owners who load up their valve cover with oil.

For those of us who just use the Q for occasional test 'n' tune nights and stoplight battles, the aforementioned oil pressure drop (which is the same thing that happens to modified GT-Rs) can be mitigated with .5-1 qt overfill, with no detectable side effects. It might affect crankcase pressure fluctuations and such, but it isn't enough that the rotating components contact the sump oil, so there's no danger of churning the oil.

I've been running 1qt over in both cars, no issues, and the oil pressure drop in the Q is gone (and I never measured the OEM fill level oil pressure in the GT-R, but I've seen logs from other cars - it was enough for me).

:)
Didn't someone here mention that we have a baffled oil pan? If so, this should be decent for keeping some oil in place on hard cornering for track days.

I guess that is the next thing I will have to look into.
 

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Never, never, never overfill. It will cause foaming and may push more oil out of the breather resulting in more deposits on the intake valves. Could you please quote the credible source of this information? And please don't say "people on the internet".

If you feel that because you are racing and need more capacity get a bigger sump. If you feel that the extra oil will result in lower operating temperatures, get an oil cooler. Don't overfill.

^^ this. I've never heard of overfilling purposefully and it being a benefit.
 

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Do they not offer a Oil-Pan Spacer in the Q50? I know they did for the G37 and the 370z, allowed you to hold more oil in the pan and maintain higher oil-pressures on track
under WOT.
 

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Didn't someone here mention that we have a baffled oil pan? If so, this should be decent for keeping some oil in place on hard cornering for track days.

I guess that is the next thing I will have to look into.
I posted the assembly drawing earlier in this thread. What most manufacturers/engines call a windage tray, Infiniti calls a baffle plate. It's not really a baffled oil pan. I've never seen the oil pump sit down in the pan like this without some kind of pickup tube. So if you get sloshing or high G, you're not uncovering the pickup....you're directly uncovering the oil pump inlet.....no bueno.
 

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I posted the assembly drawing earlier in this thread. What most manufacturers/engines call a windage tray, Infiniti calls a baffle plate. It's not really a baffled oil pan. I've never seen the oil pump sit down in the pan like this without some kind of pickup tube. So if you get sloshing or high G, you're not uncovering the pickup....you're directly uncovering the oil pump inlet.....no bueno.
Does that mean you have modified your position and agree there is a design defect?
 

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Does that mean you have modified your position and agree there is a design defect?
Just the opposite. Instead of having an oil pickup tube that is typically placed at the very bottom of an oil pan, there is NO pickup tube. It appears the bottom of the oil pump just sits in the pan. I haven't tried to dig and see about height, but from the diagram it doesn't look ideal.
 

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Just the opposite. Instead of having an oil pickup tube that is typically placed at the very bottom of an oil pan, there is NO pickup tube. It appears the bottom of the oil pump just sits in the pan. I haven't tried to dig and see about height, but from the diagram it doesn't look ideal.
Just checking.;)
 

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I think this might be similar to that "towing" thread.



While the manual says NOT to overfill (section 8-11) my dealership kept overfilling the oil above the H line (this is the 3rd time now), about 1/2 quart if I would throw in an estimate. No issues there really and I'm not concerned about that more than over tightening the drain plug. I'm beginning to think reading isn't their best suit, given that the torque spec is already printed beside it.
My dealership is doing the same thing LoL. They always overfill my engine by 1 or .5 liter. It seems impossible for them to drain out all the oil in 30min. I did check whether they put in 5.4L with new filter, but it is still overfilled. I also brought a manual oil extractor from amazon and tried myself. And my conclusion is that the engine only takes 5.05L to reach the max dot, instead of 5.2L per the manual. I have no idea what is causing this.
 

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My dealership is doing the same thing LoL. They always overfill my engine by 1 or .5 liter. It seems impossible for them to drain out all the oil in 30min. I did check whether they put in 5.4L with new filter, but it is still overfilled. I also brought a manual oil extractor from amazon and tried myself. And my conclusion is that the engine only takes 5.05L to reach the max dot, instead of 5.2L per the manual. I have no idea what is causing this.
There's oil that are lodged in some areas in the engine and not completely drained out. I see you're from Canada, but did you really mean Liter? Manual says Quarts - 5.2 without oil filter change or 5.4 with oil filter change (4.6 and 4.8 qt for RWD). Maybe the dealerships are using L unit, hence overfilled lol

On a side note, it's funny how Nissan issued a TSB just for proper tightening of the VR30 drain plugs.
 

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There's oil that are lodged in some areas in the engine and not completely drained out. I see you're from Canada, but did you really mean Liter? Manual says Quarts - 5.2 without oil filter change or 5.4 with oil filter change (4.6 and 4.8 qt for RWD). Maybe the dealerships are using L unit, hence overfilled lol

On a side note, it's funny how Nissan issued a TSB just for proper tightening of the VR30 drain plugs.
Yes, I mean lite. Here is the screenshot from the owner's manual.
91415

I know there is oil lodged in the engine but 1 or .5 liter seems to be too much.

I am interested to know about the TSB. A mechanic shop did my oil change this time. If there is anything special about tightening the drain plug, then I need to know.
 

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If there is anything special about tightening the drain plug, then I need to know.
Righty tighty, lefty loosy. This has always helped me.
 

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If there is anything special about tightening the drain plug, then I need to know.
On the VR30 engine, the oil pan is composite. The steel drain plug is threaded into a metal insert. The metal insert has saw-blade-type teeth on its outer diameter, which helps to "grab" the composite wall of the oil pan to resist itself turning when the drain plug is loosened or tightened.

When installing the drain plug, either use a torque wrench or if using a regular 3/8" drive rachet, grab the handle closer to the rotation point (to purposely shorten/lessen the mechanical advantage) when crushing the copper drain washer to prevent over-torquing bolt threads.
 

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Yes, I mean lite. Here is the screenshot from the owner's manual.

I am interested to know about the TSB. A mechanic shop did my oil change this time. If there is anything special about tightening the drain plug, then I need to know.
You're right, for some reason my brain skipped reading the funky L symbol they used in the manual I have.

Here's the TSB and there is no special about it. I'm guessing there's been a lot of stripped drain port due to misunderstood torque specs.

91416
 

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On the VR30 engine, the oil pan is composite. The steel drain plug is threaded into a metal insert. The metal insert has saw-blade-type teeth on its outer diameter, which helps to "grab" the composite wall of the oil pan to resist itself turning when the drain plug is loosened or tightened.

When installing the drain plug, either use a torque wrench or if using a regular 3/8" drive rachet, grab the handle closer to the rotation point (to purposely shorten/lessen the mechanical advantage) when crushing the copper drain washer to prevent over-torquing bolt threads.
Well..hope the mechanic knew what he was doing, otherwise I will need a new oil pan.
 
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