Best aftermarket oil thermostat solution for N54?
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Dont take this wrong way but there are more possibilities and your in denial
1. your car is not properly setup
2. Your car has airflow restrictions and issues in the engine bay
3. Something wrong with your engine
4. Your tune is not optimised for track work
5. Your cooling system is lacking.
6. your oil cooling is not setup properly.
7. Your oil is not up to the task.
Ive got a lot more mods that I listed and sorry I dont share them as most are in development and is proprietary knowledge.
No worries always want to improve. From what I have seen with other m2 owners and from what I have experienced on multiple track days with my friends m2 the m2 is proned to over heating, and since the m2 features a better cooling setup than the 1m stock for stock I struggle to understand why you aren't overheating.
1. The stock m2 (my warranty is done later this year so I will be able to collect my own data soon) from what I have seen is on the brink of overheating on a hot day at the track but no problems stock, my m235i was bum (well it had all the best parts in 2014 which meant a whole bunch of garbage parts since no one made anything for the F series back then) and couldn't drive hard enough to over heat due to all of the issues, onto the stuff you probably care about for my friend's m2 that was a bit over stock and all the lightly m2's with the full CSF cooling pack not really sure how else they could be set up since it is all bolt on. Vented hoods were included to increase air flow. The results showed extremely high temps. Otherwise I am really familiar with the F series n55 since I did it all with my m235i (despite the lack of quality parts back then), and now with the m2 despite me not having much seat time on the track with this car I do all the work for my friend with his m2 and have driven it on the track, and my own m2 is next so that's going to be fun.
2. Stock car 100%, some cars had a vented hood but I haven't seen the logs comparing similar setups with non vented hoods to conclude anything meaningful but the vented hood should help with air flow and cooling.
3. Not if all N55's driven hard with meaningful mods are seeing limp.
4. This is probably the case for almost all of the street tuned m2's out there. There are exceptions which is seanwrt who has a track tune and is running well, and active but the temps are so close to limp. Yet they are on the brink of cooling, even stock cars with fast drivers pushing them hard get near the limit of the stock cooling system and with any increase in power at all results in over heating. Stock is a non issue but you really are cutting it close. I've already got a tuner in mind to setup my car the way I like it, low boost with a larger more efficient turbo favoring timing over peak boost. Plus I will be running E85 for its evaporative cooling effects which really makes my frs happy.
5/6. Stock cars no choice. Even with the CSF (or DO88) upgraded oil coolers and radiators on a tuned m2 there are issues with oil and water temps, not much else you can do to set these things up since they are bolt on. I've seen some insane setup's like tyspeed with his V mounted giant CSF oil cooler struggle with oil temps until recently when he added the triple pass radiator and dual aux water coolers. I'm not saying there are no solutions to temperature issues, if you dump enough money into make a crazy setup you will be fine, it's just the bolt on stuff and stock stuff is not cutting it for m2 guys who are tuned. which is why I am so surprised that your 1m has zero oil cooling issues on the tiny stock oil cooler, and I'm taking it that your 1m is heavily tuned.
7. Can't say what oil the others are running but most of it is in the 5w40 0w40 range for track days, can't really go thicker than that without risking viscoities being too high to properly lube the rod bearings. When my warranty is done I will likely pick what I use on my track FRS, it will consist of an oil with a high HTSH rating of 3.5 or higher, to meet LL01 it will likely not be any higher than a group 4 base stock with a lot of group 3 mixed in with a minimum being a group 3 oil with group 3 added in, I will also look for a high TBN oil but it shouldn't matter too much since I will be doing short oci's like on my frs, weight will be 5w40 or 0w40.
I general all I can say is that what helped me the most was copying over the cooler sizes I measured on the S55 (which are the same on the GT4 cars). Ie 50% larger radiator area and around 100% extra for oil. A DCT oil cooler is also important, and for FMIC you need nothing less than the biggest you can get out there. And then water injection and outside water spray for fun as well as some extra air outlets. That sums it up for me.
Yeah, but again, since someone wanted us to be fact-based, I just ask: Where is the proof for this? Did Tyspeed share any logs or aim videos recently (done in hot and humid ambients). I would love to study that data.
Yeah I mean I was just looking for proof that the power reduction was due to oil temp. We fully agree that timing gets pulled due to iat and water temps, but I dont see any proof for oil at say 130C-140Cish, hence me asking. In theory high oil and low coolant temps is what you want for power. When people say they feel power being reduced as oil temp goes up, it is very likely actually due to rising water/iat temps which they just dont see.
Yeah, but again, since someone wanted us to be fact-based, I just ask: Where is the proof for this? Did Tyspeed share any logs or aim videos recently (done in hot and humid ambients). I would love to study that data.
Yeah I mean I was just looking for proof that the power reduction was due to oil temp. We fully agree that timing gets pulled due to iat and water temps, but I dont see any proof for oil at say 130C-140Cish, hence me asking. In theory high oil and low coolant temps is what you want for power. When people say they feel power being reduced as oil temp goes up, it is very likely actually due to rising water/iat temps which they just dont see.
There's a few threads where people have said they experienced limp mode at the track from oil temperatures which is why I originally got concerned, but you're right, it could have been from something else. Cars with AT are a whole different animal too. I don't think that IAT's activate limp mode though, just pulls timing. I'll look around and try to find someone with logs maybe, but this limp mode thread has lots of info including at what coolant temp the ECU starts pulling power. Not sure if spoolstreet allows links but I'll try: https://www.e90post.com/forums/showthread.php?t=412156
Also just in case anyone is wondering I got in touch with Mosselman and they said they don't have a flow chart for their thermostat. Not that I'm surprised or anything. They also said that the internals were designed larger than the stock one and will pose no restriction when using 10AN lines. @F87Source You had me wondering about that so I looked into it.
The few extra lap comments were from tyspeed, and a few other track guys who said you gain a few more laps if you start right at warm up 192°F compared to reaching full full somewhere in the upper 240°F range where the stock thermostat opens all the way. Again no one is providing logs which is what makes this really hard they are only posting their experience, race teams definitely won't. I will see if I can get a few people to send me logs before and after their cooling upgrades without any changes in between. But what makes it harder is some people do the thermostat delete right away (with the coming mods so the data useless since it factors the cooling upgrades) and some do not (the people that do the delete later), then they mix up the data logs. I will see what I can do. But if I can't find any we will chalk the oil thermostat delete as a possibility due to the testimony of many hard core track guys and not concrete fact. Idk since I'm chasing for every degree possible and wanted an aftermarket thermostat what's the harm in getting a high flow one.
No I don't think he shares any logs outside of his video. He's a race team right, so data for them is quite valuable since they spent alot of money to get to where they are. So they likely won't share anything outside of their videos.
Omg I can't believe I found it again: https://www.e90post.com/forums/showthread.php?t=1358492
Scroll down to v8baits screen shot of the ECU tables shaking yellow and red limp mode for oil and coolant temps. Based on these values you can look at track data logs and see what hits limp first. What I've seen in some was oil getting there before coolant, so that's why I want to be able to get every single degree possible.
I'm not sure if there is a difference between the n54 and n55 because I remember reading the n55 limps oil at 280°F and fully limps it out at 300°F. I will have to look for that one as well. But if I'm mistaken then I'm gonna eat my words and say you're correct it limps coolant and not oil, and thus pulls power because of coolant and not oil.
So my conclusion on this point is that if the n55 oil yellow limp isn't at 280°F like I speculated then it most likely is a coolant limp like you said, it can't be an iat limp because iat's just stayed in the 50°C range and higher the whole time lol. That also means on my friends m2 the limp we experienced was due to coolant only if indeed 270°F and up is not oil limp. Oh and to add on it also means all of the m2's I have discussed earlier just had crazy high oil temps and they were not near oil limp mode, but they were near or at coolant limp mode.
Edit- I should also say this too, I have seen alot of m2's limp from high coolant temps as opposed to oil temps too. I just reviewed more logs on f87post and it seems coolant limps are more common, maybe the dct cooler? So I have seen both cases happen (if indeed oil limp is 270ºF, if not and it is indeed higher then I have never seen an oil limp lol). But again this is really dependent on how fast the driver is, if it is stock (never seen a stock one limp just come close to hitting limp mode temps due to super high ambients) or modded, and ambient temps. For a heavily modded car (turbo upgrade) oh yeah that things is going to limp no matter what unless you go extreme custom cooling.
Edit 2- @Asbjorn contacted my friend, he does not have any logs from the jb4 since he deleted jb4 mobile when he switched to flashing. But it turns out my memory was wrong and he recalled we went deep into the 250ºF range with coolant so we definitely coolant limped.
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Good to know! The moseelman unit is still alot more expensive than an improved racings unit + delete plate so I think I'll go with the cheaper option.
Yeah your thread also says oil begins pulling power at 270°F, just like what I read for the n55. While the thread I linked with the ECU tables show way higher, maybe yellow warning is after it pulls power?
Idk, but all I have read for the n55 is oil temps above 270°F means power is pulled, this could be a huge misconception but I can't find anyone who posted the ecu tables for the n55 so far.
Update: I stil can't find concrete proof, there are threads that say 270ºF, some now add in the number 280ºF, and some still say 300ºF+.
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Thanks for investigating. All I could find was this description of limp modes for N55. They look similar to N54. Haven't seen any tuning tables.
PS these are also the values I lowered intentionally in my low boost map for track practice. Just for some added safety.
Also went through the S55 technical training pdf and newtis, couldn't find anything. Anyhow, you experience is the same as mine, coolant typically hits the limit earlier than oil. But for the tuned S55 I meet at the track, hearsay is that the DCT overheats earlier than anything. It might be because they get some slip with their tunes though, who knows.
That makes it even harder when we talk about the m2 since alot of these guys have DCT's and I don't even know the limp mode temp for that, so who knows if that is causing it.
I wonder how thin the oil is at this temp, surely at 150ºC it has to be shearing easily. I think the oem HTHS rating is below 3.5 which would not be good for wear and tear on the bearings, this could be a reason why so many N55's spin their bearings due to heat.
Anyways I was looking at redline 5w40 and it meets bmw LL01 requirements (although not certified by bmw as LL01) and it is some really good stuff. It likely is a group 4 base with a ton of esters (so a bunch of group 5), it has a 6% NOACK, and has an incredibly high 4.4 HTHS (highest I've seen for a 5w40, maybe motul's full race oil with ester base 300V is greater but it is so expensive) which is 0.8 higher than the LL01 approved motul xmax 0w40.
It has been proven that the oil pressure will drop below idle level during hard braking on cars running non-M N55. Not many tracks out there do not require late hard braking if you want to set a decent lap time. So I would put my money on that being the root cause of unhappy bearings.
Well you saw my rod bearings after 150.000kms and plenty of 130-140C action. I rarely ran the same oil for much more than 5000kms though, and only started taking it to the track two years ago.
Yeah not bad, quite good actually! I almost forgot you pulled your bearings lol. What oil and weight did you use?
0w40～5w40 mostly, just castrol edge, mobil 1 or amsoil. Did try the expensive racing stuff one or two times just to see if it would lower oil temps. It didn't...
Alrighty then I will probably just settle for motul 8100 xmax 0w40 since it has bmw's LL01 certification and has a pretty good HTHS rating, I might get valvoline advanced 5w40 if I can find it.
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Keep in mind that the Z4, compared to the 1M, has a cavernous front end. The 1M is choked to hell in my opinion.
IMHO you have access to Motul, for track and wanting headroom you should definitely be running Motul 300, not 8100. Certs are irrelevant for track use. Motul 300 is a motorsport application and tough to beat.
Filippo
IMHO you have access to Motul, for track and wanting headroom you should definitely be running Motul 300, not 8100. Certs are irrelevant for track use. Motul 300 is a motorsport application and tough to beat.
Filippo
Agreed but it is not cheap with the number of track days I'm doing per year, especially since I'm flushing it out at the end.
So long as an oil has a good enough HTHS rating it should do fine under high temps, cheap does not mean bad necessarily which is why specs matter. But at the end of the day what matters most is your used oil analysis after track days. I'm also hearing good things about Pennzoil platinum euro 5w40, the gtl additive makes for an oil with a super low NOACK of 6.1, and it has a HTHS of 3.6 which is the same as xmax. I might give this a shot since it is half the price of motul with similar specs, albeit the base oil is likely group 3 whereas motul probably has a better blend. Again trial and error with used oil analysis is the plan.
I should have expanded. 300V isn't run for just lubricity factors. I understand it will also run cooler.
If you are in the USA - FCPEuro sells 300V and they have a lifetime replacement/warranty on everything including oils. They are happy to have you send oil back.
Should not be run in street car use - does not have the detergents and modifiers for that application.
Filippo
Ah good ol FCP.
HTHS is high temp shear strength which is important for track use.
Again it's not as simple as buying the most expensive oil possible, sometimes you only get a miniscule gain for the amount you pay. 300V is a fully ester oil so group 5 and as a result probably has an insane HTHS rating. However I might not need all of that since I don't do endurance racing and I don't plan to push my car past 132°C oil temps as I will be taking cooling quite seriously.
So instead of wasting money on 300V and having to flush my oil system everytime I use it so I don't have different oil types mixing (also not sure if 300v has enough group 4 paos to promote seal swell which is important), I will investigate oils capable of street and track useage. Currently it's motul 8100 xmax, Pennzoil platinum euro (heard it's based off of the helix ultra), and Valvoline advanced if I can get it. Then I will do use oil analysis testing on all of these oils to see if they cut it, if they do then no need to waste money on 300v. Even if it was free via FCP, I don't want to hassle myself flushing the oil system - not draining and refilling but flushing. It'll suck even more if you have an accusump.
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