Coolant temp at track

[bigjae46]

Our expansion tank cap is 2bar? (29psi). General rule of thumb I've heard is 3 degF for each PSI, so 29PSI would yield an additional 87 degF to the boiling point. Coolant mixture also affects boiling point.

Me personally I would be more worried about what temp risks the head getting warped versus the boiling point. But boiling point is definitely a factor!

Factory is 20psi or lower.

If you have liquid coolant circulating then you won’t run into head warping issues. You’re circulating 250-280 degree oil through the head.

You run into problems when coolant boils. It’s like a run away train…boiling coolant drops the pressure which lowers the boiling point and then you get more boiling. All the while temps are spiking and then you run the risk of warping the head.

[eacmen]

Our expansion tank cap is 2bar? (29psi). General rule of thumb I've heard is 3 degF for each PSI, so 29PSI would yield an additional 87 degF to the boiling point. Coolant mixture also affects boiling point.

Me personally I would be more worried about what temp risks the head getting warped versus the boiling point. But boiling point is definitely a factor!

[bigjae46]

Reading through this as I’m trying to figure out where to set my warning thresholds on my Autometer Elite gauge for my S54 swapped E36. I feel like I had it set a bit too low for the warning and was getting distracted by the warning light. I just upped the high warning to 220 and the high over warning to 230.

I'd say about 215-220. There is a risk of a boil over above that and then you'll be in a world of hurt. Or use an aluminum expansion tank with a higher pressure cap so you get some more temp capacity. IIRC, a 29psi cap will has a capacity of 248 degrees F.

[mrgizmo04]

Ran fine last month in 65f weather. But also added CSL airbox since then.

I'm assuming you got a different tune with a CSL box? Have you confirmed this to NOT be the source of your overheating?

Sent from my SM-S911U1 using Tapatalk

[BeardedRyno828]

Reading through this as I’m trying to figure out where to set my warning thresholds on my Autometer Elite gauge for my S54 swapped E36. I feel like I had it set a bit too low for the warning and was getting distracted by the warning light. I just upped the high warning to 220 and the high over warning to 230.

[GolanM3]

When I see your coolant temps readings of 215f or 224f I wonder if I have overheating issues or I'm too conservative. The needle will stay dead center until 204F, once it gets to over 205F it starts to move to the right, which makes me very uncomfortable, should I not expect it to stay dead center on a hot track day? the higher I've seen it before decided to let it cool down was 210F. At what temp the warning comes up?

[Hyperboost]

I was all the way up to 224F on track this Tuesday. It was a very hot day at the track. Thompson

[Casa de Mesa]

Quick update: Didn't have time to do a complete refresh but couldn't skip out on a hpde. Prior to this event I cycled out about 2 reservoirs full of the 50:50 mixture and put in distilled water. With rough calculations was hoping to get it to 60:40 mixture. Also noticed that the coolant might've been slightly overfilled previously took about 3 turkey basters to get the level to start dropping.

Results: Engine temps 3/4 on gauge. Coolant temps rose to 210-215 by the end of full 20 minute sessions. The ambient temp was about 5 degrees cooler outside and little to no traffic on track. Letting the engine cool between sessions was enough to keep going. Also, beat my PB by .7 seconds so I wasn't taking it any easier.

Complete refresh with OE rad and CSF oil cooler will happen in the winter.

Great news!

[jk715]

Quick update: Didn't have time to do a complete refresh but couldn't skip out on a hpde. Prior to this event I cycled out about 2 reservoirs full of the 50:50 mixture and put in distilled water. With rough calculations was hoping to get it to 60:40 mixture. Also noticed that the coolant might've been slightly overfilled previously took about 3 turkey basters to get the level to start dropping.

Results: Engine temps 3/4 on gauge. Coolant temps rose to 210-215 by the end of full 20 minute sessions. The ambient temp was about 5 degrees cooler outside and little to no traffic on track. Letting the engine cool between sessions was enough to keep going. Also, beat my PB by .7 seconds so I wasn't taking it any easier.

Complete refresh with OE rad and CSF oil cooler will happen in the winter.

[jk715]

Thanks for the feedback and tips. WOLFN8TR I'll be sending payment for those viton o-rings shortly. Rich022 I monitored using OBD. I'd like to avoid ww if possible, but will do a 60/40 water/coolant mix during refresh (pump/tstat/coolant)

[Casa de Mesa]

I had a similar issue when refreshing my cooling system. When replacing my water pump the small O-ring on one of the two hard pipes leaked causing issues. Come to find out ECS sent two different sizes, the smaller one was installed just before the water pump and it caused air to be sucked into the system and would slightly drip when the car was off. Also those two #8 orings were already subject to compression set in just a months of use when I tore down the system to replace the smaller O-ring. This is the main reason I put together the Hi-Temp O-ring Kits.

Oh that's right. Just found out about this kit the other day. Love that you did this. Will probably order this to have on hand.

Regarding the set in that took place on those o-rings after a couple of weeks/months, to that I say "yay!!". Hard to believe they are spec'ed that way from the factory

[WOLFN8TR]

Be careful with the #8 O-rings that the thermostat housing attaches to:

https://www.realoem.com/bmw/enUS/sho...diagId=11_3010

Part no: 11537830709. I thought I was super careful, but botched one on install. I reassembled everything (EVERYTHING), filled the coolant and watched it start draining out of that front O-ring that attaches to the thermostat housing. I'd buy a spare O-ring or two just in case...

I had a similar issue when refreshing my cooling system. When replacing my water pump the small O-ring on one of the two hard pipes leaked causing issues. Come to find out ECS sent two different sizes, the smaller one was installed just before the water pump and it caused air to be sucked into the system and would slightly drip when the car was off. Also those two #8 orings were already subject to compression set in just a months of use when I tore down the system to replace the smaller O-ring. This is the main reason I put together the Hi-Temp O-ring Kits.


Complete set of Hi-Temp Silicone and Viton O-rings for the S54 Cooling System and Power Steering and SMG Caps!


1- Temp Sensor- 1
2- Bleeder Screw- 1
3- Exp Tank Return Line- 1
4- Water Pump Lines- 2
5- Exp Tank Cap- 2
6- Radiator Hose Fittings- 2
7- Water Pump Pipe “large”- 2
8- Power Steering/SMG Caps- 2
9- Water Pump Tstat Housing- 1
Two squeeze tubes of Super lube.

"Summer Sale" 14 O-rings and Lube for $45 Shipped via Priority 3 Day.
Please send funds via PayPal as a gift or add the 3% Fee to [email protected]
I have 100% Feedback on eBay so buy with confidence. Wolfn8tr on eBay: https://www.ebay.com/usr/wolfn8tr

[S14]

I noticed a huge improvement in on-track cooling performance by ditching the aux fan + clutch fan and switching to an E46 non-m electric fan + shroud I had. A SPAL fan would probably be better but I didn't have one on hand.

They're actually the same fan motor just a different fan blade and shroud. The aux fan shroud is honestly pretty restrictive and I suspect that is why I had issues. Other than that my cooling system is all new OE front to back (40:60 coolant to water).

Ditching the aux fan probably isn't great for A/C performance but that is less important to me than cooling system performance.

I bought a non M E46 fan and it didn't fit at all. Do you have any photo's of your installation? Are you running the stock oil cooler?

[heinzboehmer]

Be careful with the #8 O-rings that the thermostat housing attaches to:
https://www.realoem.com/bmw/enUS/sho...diagId=11_3010

Part no: 11537830709

I thought I was super careful, but botched one on install. I reassembled everything (EVERYTHING), filled the coolant and watched it start draining out of that front O-ring that attaches to the thermostat housing. I'd buy a spare O-ring or two just in case...

Yup, I've done this as well. Luckily my local dealer had them in stock.

[Rich022]

A few observations; the underdrive setup will reduce your waterpump efficiency as it's spinning at a lower rate than stock. However on track, airflow thru radiator etc. should make up for that.
230F - was this temperature noted via your OBD ? or just a guess via your instrument cluster. Tracking my M3 hard at 95F -105F Texas water temps MAX have ever been 210F via OBD. This is with stock AC unit/condenser still in place. Also, a 50/50 coolant ratio provides less cooling efficiency say vs. a 80/20 or 90/10 which I run with WW.