[F87source]

Originally Posted by ZM2

Current setup and cooling mods:

Power - 470whp
BM3 Stg 2++ Multimap with E50
TTE460 turbo
Dorch Stg 1 HPFP
Turbosmart plumb back BOV
HJS 300-cell downpipe
Akrapovic Exhaust
MST v2 inlet
3.5-bar TMAP
Stock airbox & filter

Cooling
do88 radiator
do88 aux radiator
do88 oil cooler
BMS oil cooler valve
Stock DCT cooler with larger M2 CSR DCT oil pan
Evo3 IC
Suvneer GTS vented hood
BM3 MaxCool setting
E39 in line additional coolant pump (with F87source help)
E50 fuel
10w-40 300V (new formulation)
100% water + wetter in the summer

Good to hear the exchanger isn’t needed, but I still think you all are thinking too much about what the exchanger does on the street vs what is happening in my logs on track at peak temps.

No doubt the coolant is following oil temps as it warms up, and could be lower in the beginning of the stint without the exchanger. But seeing how quick coolant temps jump under WOT tells me the extra headroom from the lower coolant starting temps might get you an extra lap?

I’m more concerned about peak temp management, and now that oil temps are in check it’s clear to me in the latest do88 logs vs last year with CSF coolers that the cooling bottleneck is on the coolant side and the exchanger is actually helping keep coolant temps from rising above 250F by letting the oil side absorb excess heat from the coolant.

I need you guys to read thru my comments above and review the logs in detail and throw out the traditional thoughts about what the exchanger does during warm up, and instead focus on peak temp dynamics and management, so we can all decide if the coolant system efficiency (capacity & airflow) or the exchanger is more of the issue.

I'll get back to you in a bit, but I'm currently scrambling to get a few reviews released and finish installing my mmi and 2 piece brake rotors.

[F87source]

Originally Posted by ZM2

Not a lot bc the OG M2 is very limited on room up front. This is the best that can be done for a daily driving track car:

https://www.do88performance.com/en/a...-aluminum.html
https://www.do88performance.com/en/a...-aluminum.html

So, if we can’t increase capacity, that pretty much leaves:

-Removing the exchanger (if it’ll actually help and not hurt peak coolant temps)
-Improving airflow to the radiator with a shorter & less thick IC
-Water injection to lower combustion & engine temps

Seems like a roll of the dice at this point to know which will help the most.

Do the cheapest ones first.

[edycol]

Originally Posted by F87source

The F series n55 heat exchanger doesn't have internal seals, that's the E series cars with the heat exchanger on the oil filter housing.

Ah yes, I forgot it is in a different position in addition to air-cooled oil coolers.

[AmuroRay]

I’ll admit, I didn’t consider the idea that the exchanger could be helping the coolant temps, but as it was pointed out, oil takes longer to cool - I don’t see the exchanger helping coolant temps as much as adding cooling capacity to the oil cooler.

You can see on most cars that the coolant (check @M2guru thread for his most recent logs) cools quickly, even when approaching near the “limits”

Easier to delete it, then go with a new Intercooler - even if I think the VRSF/BMS/eTc are upgrades

[AmuroRay]

Originally Posted by edycol

As for protection you mentioned, 0W and 5W do not have anything with exchangers. That si cold start. 5W will do good until -30f, I started X5 35d at -42f having Valvoline 5W40 in the engine. 0W is obviously better choice in those temperatures. Protection depends on HTHS.

That’s not what I said - I pointed out that the 0w and 5w flow well enough to offer protection even at 0F temperatures, so an exchanger isn’t really a benefit in those situations.

[F87source]

Originally Posted by AmuroRay

I’ll admit, I didn’t consider the idea that the exchanger could be helping the coolant temps, but as it was pointed out, oil takes longer to cool - I don’t see the exchanger helping coolant temps as much as adding cooling capacity to the oil cooler.

You can see on most cars that the coolant (check @M2guru thread for his most recent logs) cools quickly, even when approaching near the “limits”

Easier to delete it, then go with a new Intercooler - even if I think the VRSF/BMS/eTc are upgrades

I wouldn't say deleting it is easy, you need custom lines.

[AmuroRay]

Originally Posted by F87source

I wouldn't say deleting it is easy, you need custom lines.

Why do you hate fun, freedom and America?















Don’t mind me, Im drinking

[edycol]

Originally Posted by AmuroRay

That’s not what I said - I pointed out that the 0w and 5w flow well enough to offer protection even at 0F temperatures, so an exchanger isn’t really a benefit in those situations.

Soery, I misunderstood. Yes, at 0f they are both fine. Actually at 0f 10W will be fine too.
Exchanger is of benefit that it warms up oil faster. One can argue that that will slow wear a bit. But primary purpose is to boost mpg.

[ZM2]

Well, I’m traveling all of September and will then be doing my first NLS Nurburgring race in October, so I don’t think my M2 will see hot weather again for testing until May/June 2024.

M2guru I’ll be interested in seeing your logs in the meantime with the do88 oil cooler if you still find some hot weather.

Altho, I’m more curious to see what your coolant temps will do if you put on a larger IC (more engine power to be cooled and potentially worse airflow to the radiator), and if the do88 radiator will be enough to keep in check, or if you’ll have to do one of the remaining options we’ve just listed.

[AmuroRay]

Originally Posted by ZM2

Well, I’m traveling all of September and will then be doing my first NLS Nurburgring race in October, so I don’t think my M2 will see hot weather again for testing until May/June 2024.

M2guru I’ll be interested in seeing your logs in the meantime with the do88 oil cooler if you still find some hot weather.

Altho, I’m more curious to see what your coolant temps will do if you put on a larger IC (more engine power to be cooled and potentially worse airflow to the radiator), and if the do88 radiator will be enough to keep in check, or if you’ll have to do one of the remaining options we’ve just listed.

Is he planning on upgrading the Intercooler and radiator?

[M2guru]

Originally Posted by AmuroRay

Is he planning on upgrading the Intercooler and radiator?

Next track day is 9/5. Ambient temps look to be similar to last event for an apples to apples comparison. Two changes: 1) I straightened stock radiator fins and 2) do88 oil cooler and fender liner opened up.

Tempted to upgrade intercooler because I cannot see a way to clean out the 5-year old CSF intercooler - guessing it's not great. Might do that next year. Radiator and/or aux radiator would be after intercooler.

[AmuroRay]

Originally Posted by F87source

I wouldn't say deleting it is easy, you need custom lines.

Following up on this - is that expensive? I'm not as hardcore as ZM2 or M2Guru - but I would love to consistently track my car, though I'm not sure this is something I would personally do - especially since I probably can't carry the speed/pace they do. I doubt I would max out what I have.

[ThreeStripes]

Originally Posted by AmuroRay

Following up on this - is that expensive? I'm not as hardcore as ZM2 or M2Guru - but I would love to consistently track my car, though I'm not sure this is something I would personally do - especially since I probably can't carry the speed/pace they do. I doubt I would max out what I have.

This is only a issue for guys making big power pushing hard in summer heat. My BM3 S291 car with CSF intercooler has handled high 80s no problem.

[F87source]

Originally Posted by AmuroRay

Following up on this - is that expensive? I'm not as hardcore as ZM2 or M2Guru - but I would love to consistently track my car, though I'm not sure this is something I would personally do - especially since I probably can't carry the speed/pace they do. I doubt I would max out what I have.

Probably, it's definitely not going to be cheap.

So what you need is to do the following:

1) Retain stock fittings: go to an AC shop (because they are familiar with this crimp style fitting bmw uses for their oil line) and get them to cut off and then recrimp the oil cooler fittings to new lines that go directly to the oil cooler housing - again the fittings on the oil filter housing will need to be recrimped to the new hoses.

2) AN conversion: you'll need to change out to an AN capable oil filter housing or run adapters - I think vac sells them. Then you'll somehow need to create bespoke fittings that adapts an to the O-ring plug style fittings bmw uses on the stock oil cooler. So either have a shop cut off the stock fittings and weld them to an an fitting or something. But this is what you need to do if you want to run AN lines.


Personally I'd prefer option 1, because I don't like the idea of welding small diameter pieces especially because most shops will not purge them and this can create stalactites and restrict flow. Crimping shouldn't have this negative effect - unless somehow it was crimped so hard it smashed down the fitting.



Ok now some more options, but affecting the coolant loop:

1) Assuming the heat exchanger is capable of 270F - 300F (this should be the case) without any coolant flowing through it to reduce temps (not sure about this). Then we can leave the oil loop as is. We would however modify the coolant loop which is way easier. As coolant is under far less pressure and their associated hoses are capable of being fastened down with standard work gear clamps without failure. So remove the coolant hoses going to the heat exchanger. Cut the fittings off the hoses going to the aux water pump (if you have an m235i, m2 doesn't have this pump for whatever reason and now would be a good time to retrofit one). Then create your own hoses clamping those stock fittings to the new hoses. The new hoses would also go from the aux rad to the aux pump, and then plumb back to the main radiator.

This is the easiest method and it should be diyable, and therefore cheaper.

[ZM2]

Originally Posted by ThreeStripes

This is only a issue for guys making big power pushing hard in summer heat. My BM3 S291 car with CSF intercooler has handled high 80s no problem.

GasBurnlife(landapanda) was hitting 250F coolant on the straight at Road Atlanta. Stock power. Lots of suspension mods and sticky tires.

[F87source]

Originally Posted by ZM2

GasBurnlife(landapanda) was hitting 250F coolant on the straight at Road Atlanta. Stock power. Lots of suspension mods and sticky tires.

Could be bent ac condesor fins restricting airflow. But it's possible the stock radiator is really insufficient because the m23ir is detuned to 270whp.

[ThreeStripes]

Originally Posted by ZM2

GasBurnlife(landapanda) was hitting 250F coolant on the straight at Road Atlanta. Stock power. Lots of suspension mods and sticky tires.

With an upgraded intercooler? Road Atlanta’s back straight means a long 5th gear pull so that could be as much of a factor in this as ambient temps.

I’m running WRL race pace at Barber for 25mins without issues but never see 5th gear so it’s never been a problem. I am eyeing a trip to Road Atlanta next spring so I guess I’ll find out.

[ZM2]

Originally Posted by ThreeStripes

With an upgraded intercooler? Road Atlanta’s back straight means a long 5th gear pull so that could be as much of a factor in this as ambient temps.

I’m running WRL race pace at Barber for 25mins without issues but never see 5th gear so it’s never been a problem. I am eyeing a trip to Road Atlanta next spring so I guess I’ll find out.

Stock IC.

Yup, 140mph+ is the death zone for our cooling systems. Even with my latest oil cooling upgrades, I know if I was at Summit or WGI and hitting 155mph in the summer, my coolant temps would be out of control.

Guess I’ll have all winter to contemplate next changes, unless someone else starts testing this stuff in Florida or TX.

[ZM2]

Also, not to be more pessimistic, but I’m realizing I was running the Stg 2+ MM v1.2 map on my latest outing.

That map is 450-460whp on my car, vs v1.1 that I was running last year (480whp) and a slightly more boosted version of v1.2 (what I call Stg 2++ MM v1.2) that Halim gave me which gets me back up to ~470whp.

I meant to run the Stg 2++ MM v1.2 but clearly the cooling system still wouldn’t have been able to handle it, esp if it were a hotter day and higher speed track.

The upside of Stg 2+ MM and Stg 2++ MM v1.2 is boost now drifts lower in upper RPMs to keep the turbo more efficient and generate less heat up top.

So, the tune (mis)selection in this case was also helping keep coolant temps lower.

[GasBurnlife(landapanda)]

Originally Posted by ZM2

Stock IC.

Yup, 140mph+ is the death zone for our cooling systems. Even with my latest oil cooling upgrades, I know if I was at Summit or WGI and hitting 155mph in the summer, my coolant temps would be out of control.

Guess I’ll have all winter to contemplate next changes, unless someone else starts testing this stuff in Florida or TX.

Zack - happy to take your car to Florida this winter for some testing

[ThreeStripes]

Originally Posted by GasBurnlife(landapanda)

Zack - happy to take your car to Florida this winter for some testing

Did you ever run Road Atlanta after upgrading your intercooler to see how that impacted coolant/oil temps there?

[ZM2]

Originally Posted by GasBurnlife(landapanda)

Zack - happy to take your car to Florida this winter for some testing