that's not what real oem says - for the m2 atleast, which is why I am skeptical until I get my own data with an IR thermometer.
That's actually not what real oem says for your model of n55 either (left is outlet right is return), the hoses look different though. https://www.realoem.com/bmw/enUS/showparts?id=KG73-USA-09-2010-E92N-BMW-335i&diagId=17_0375
Definitely, but a checkvalve for the accusump does - which was the whole point of this thread.
I could've had the flow/return mixed up in the OP. I actually have it installed on the right side port right now. Not that it matters at all for me. As stated in the OP, a check valve isn't necessary and I didn't install one. Flicking on my Accusump with the engine off brings oil pressure up to 60psi+ almost instantly. I am not concerned about oil being pushed backwards through the oil filter and oil pump. It just wouldn't happen. oil pump is still spinning forward even if it's just grabbing air.
As for the oil cooler, yeah I think it's more ideal to have the Accusump installed on the return side purely because of oil temps. I'd rather be feeding the Accusump oil that has been cooled to normal operating temp. Accusump recommends you install the accumulator as directly as possible. You could feed it into the main oil galley if you wanted to. It's all a closed loop pressurized system though so installing it pre oil cooler, post oil cooler, directly into the block, it's all the same thing really expect for any pressure losses that occur from installing it further down stream. Tapping into the oil return/feed lines also allows you to monitor the oil pressure impact the Accusump is having since it's also pre oil pressure sensor.
All that really matters is that the Accusump is being fed filtered oil. seeing as how the first thing the n5x does is filter the oil post oil pump that is a non-issue for us. If you want a check valve installed in one of your oil cooler lines then yeah you need to verify which is the feed/return to get the direction correct. I personally don't think having one matters much.
I admit, the accusump seemed like black magic to me at first too. How does it charge? how does it actually work? will i mess anything up? It's a really simple device. Just install the damn thing it's really not this complicated lol. Now that I have one I see all sorts of track cars with these things mounted in the trunk, passenger seats, under the car, under the hood... whatever is convenient.
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I won't have the stock ofh since I will be using a delete plate for the thermostat so I will have to use a t fitting. I also want a check valve because I don't want to cause surge in the oil pump which could damage the pump, just like how co pressor surge damages a turbo. I also found an extremely high flow check valve which shouldn't impede oil flow in my loop.
But anyways thanks for clearing things up for me!
Surge on the oil pump? It is mechanically driven and regularly works against 120psi+ of back pressure. Maybe it's just something I'm ignorant about but I don't see it as an issue.
I never thought about it like that, yeah I guess it was designed to encounter alot of oil pressure, but I don't want to risk it since if the oil pump fails the engine will fail too.
I've decided to order the return line for my car and have a local shop add a fitting to it for the Accusump. I'm really going to have a hard time fitting in the same exact spot as OP since I have an expansion tank on that side, but also because I need a better cold air intake that will likely have a 3-4" pipe in the same area to get to the wheel well. Race cars get complicated quick. Maybe the accusump gets plumbed to the rear behind the bumper? That would make the wiring less complicated at least.
Anyways, I finally got my first N55 torn down and am going to do a capacity test for the oil pan. I haven't decided what pressure switch I'm going with on the Accusump, it depends on the oil pan's true capacity as well as ECUTek's ability to control idle oil pressure. Ideally I want something that just connects to the ignition and runs itself, without a switch like OP has. I'm also trying to understand what might happen when the accusump releases the oil to an already "full" pan at idle (danger to seals, etc.)
Anyways, I finally got my first N55 torn down and am going to do a capacity test for the oil pan. I haven't decided what pressure switch I'm going with on the Accusump, it depends on the oil pan's true capacity as well as ECUTek's ability to control idle oil pressure. Ideally I want something that just connects to the ignition and runs itself, without a switch like OP has. I'm also trying to understand what might happen when the accusump releases the oil to an already "full" pan at idle (danger to seals, etc.)
What car do you have again? And yeah you can probably run the accusump to behind the rear bumper where the rear bumper carrier is. But the cons of running such a long loop is that it increases the chances of leaks if a hose chaf's on something, the oil loop will contain more dirty oil when you do oil changes, and the loop will contain more cold oil which could be too viscous when the accusump does dump.
Oh it belongs to the blue M2 in this picture.
He blew a piston ring so the engine was out.
I cannot think of any M car that has seen more track time with slicks than this M2. I don't know what tune he was running though. What I do know is that he sprayed with 50/50 wmi.
Anyhow, I will keep my baffle as is, it is not far from the M2 design. Only problem is the electric pump not flowing enough ever. But given how nice my rod bearings looked after all the track days I am not too concerned.
I don't know. I assume it was caused by greed leading to an overly optimistic tune combined with pushing hard at the limit. He was competing almost every weekend and winning against the tuned S55 cars in the area last year by outgripping them. He would often complain about his dct transmission overheating during these competitions. This year he was moving on to a larger and more power demanding track, and he did change the tuner of his car while running WMI. Who knows what they tried to do.
Oh dang.
I always had a question, do you have to purchase track insurance in China or does the driving insurance cover it?
If you damage the track you pay. No insurance.
If you damage your car you pay. No insurance.
If you damage yourself the mandatory insurance they require everyone to buy before entering will cover up to a certain amount.
This is how it is for street cars. One local video went viral explaining how a guy crashed his brand new M5 and had to pay a huge fine for damaging the track. They wouldn't hand him over the wrecked M5 until he paid and local news picked up the story. Fortunately most other tracks are pretty nice and don't charge anything for pulling you out and rearranging the tire wall.
For official competitions I believe you can buy track insurance and a few teams may also have car insurance.
Oh wow, we have track insurance here but the initial fee and deductible is insane. Ah the life of a car guy, everything is expensive.
Well, at least you don't need to pay for any cars you might crash into. Likewise, if someone hits you on track, they don't need to pay for the damage done to your car...
And I have to admit, during the last 10mins before any round of time attack begins, thats when it happens. I know I am entering a track with no speed limits, together with a bunch of testosterone driven males who all wants the same silly trophy that cost nothing to produce. And I start thinking about how there is only a small oil leak, a cooked brake pad, a loose bolt or a slight misjudgement between me and going home in a taxi or not at all. That's when I say hello to some of the biggest fears in my life and we have a pleasant talk about what they have been up to recently.
But then you put it in first gear, and you forget about all of that.
Anyway, this is exactly why +90% my track practice is just gokarting... specifically the slow kind that you cannot possibly damage, even if you tried your best.
Anyway where were we? Oh yes accusump... I didn't.
