Engine Over Heat in Summer?

[jml]

Overall heat load on the drive train are really a function of ambient, humidity and load. If you are PUSHING the car, it will overheat in anything above 80 degrees - fact. Water and tranny temps are the things that start to affect the cars response. Water temps on the warnings, tranny temps on warnings and shift responsiveness and speed.

It was the same way for me on my E46. Constant high RPM and load drove it to overheat, even with upgraded water cooling capacity.

If your car is not overheating, you're not going fast enough.

[Eugene-TAIWAN]

Originally Posted by jml

If your car is not overheating, you're not going fast enough.

[wwjd15]

Originally Posted by jml

Overall heat load on the drive train are really a function of ambient, humidity and load. If you are PUSHING the car, it will overheat in anything above 80 degrees - fact. Water and tranny temps are the things that start to affect the cars response. Water temps on the warnings, tranny temps on warnings and shift responsiveness and speed.

It was the same way for me on my E46. Constant high RPM and load drove it to overheat, even with upgraded water cooling capacity.

If your car is not overheating, you're not going fast enough.

E46 may be a bit different. My friend's stock E46 overheated almost every time during hot days, let's say 95F +. But mine had no problem.
Maybe I'm not fast enough then.

[lucid]

Almost all stock cars will overheat eventually if they are pushed hard for an extended period of time. The question is when that can be expected to happen and under what circumstances. 6-8 hots laps does not sound much to me, regardless of how hard the car is being driven, so I think there is reason to double check and make sure the cooling system is working properly. Having said that, I have not pushed this car in 100 degrees, so I have no personal experience in those conditions. However, I do know that you can push it for 10-15 minutes in 80 degrees without overheating the engine.

[Gearhead999s]

Originally Posted by lucid

Almost all stock cars will overheat eventually if they are pushed hard for an extended period of time. The question is when that can be expected to happen and under what circumstances. 6-8 hots laps does not sound much to me, regardless of how hard the car is being driven, so I think there is reason to double check and make sure the cooling system is working properly. Having said that, I have not pushed this car in 100 degrees, so I have no personal experience in those conditions. However, I do know that you can push it for 10-15 minutes in 80 degrees without overheating the engine.

I have done 40 minute sessions in 90f heat with no issues.I find that the oil temp stabalizes at about 130c(266 f) after 10 minutes of tracktime.I have never had a temp warning in either of my E92 M3's on the track.

[quads]

Depends on lots of variables in addition to ambient and humidity...
1) track layout (more corners, less high speed straights = less cooling)
2) how you drive (if you're driving in or as if in a racing taking the race line)
3) how many laps in a session do you go all out (I often will take a slower lap to cool things down before hard laps)

[MaxL]

Originally Posted by VictorH

How do you know that? Just asking.
Boiling point of radiator fluid is somewhere in the 225-235F range and radiator systems operate under 10-15 psi pressure which will raise the boiling point another 20F or so. I don't think his radiator fluid is necessarily that close to boiling, but there's no doubt that both the water and oil are pretty darn hot. Oil at 270 is frying hot and if this were conventional oil it would be breaking down. I think it's hard to know which sensor triggered the limp condition, but in mind mind both are running pretty hot.

Most modern BMWs start protective actions (disabling AC, reducing power etc) after coolant reaching ~240F or 116C, so it is reasonable that a warning would be about 10F before that, as shown on the graph. To me it seems they are being overly cautions, but they definitely know more than I do.

Oil on the other hand is far from its limits. In 335s, especially one's without extra oil cooler, their inferior oil is routinely at 250-260 in city, and I've seen very close to 300 without limp modes.

[ShadeD1]

I had the same issue at TWS last year. It was august and I was basically alone on the track for 30 min. I got the same issue, but backed off for a lap and it was ok. I'm a little concerned that next weekend at MSR Cresson will be so hot I have the same problem.

[wwjd15]

Holly overheat.... Today I'm at SOW, my engine oil overheated every 2 laps, tranny overheated in the early morning as well. The outsie temp was around 70-85F, not that hot. I guess it has a lot to do with track layout. But damn,,,, I see engine oil cooler and possibly tranny cooler in the near future.

[R A W L S]

Originally Posted by wwjd15

Holly overheat.... Today I'm at SOW, my engine oil overheated every 2 laps, tranny overheated in the early morning as well. The outsie temp was around 70-85F, not that hot. I guess it has a lot to do with track layout. But damn,,,, I see engine oil cooler and possibly tranny cooler in the near future.

By the experiences posted above and by my track experience it seems like your car is overheating too quickly. Maybe have it looked at before molding it.

[wwjd15]

Originally Posted by R A W L S

By the experiences posted above and by my track experience it seems like your car is overheating too quickly. Maybe have it looked at before molding it.

Thanks for the advice. I'm going to two different tracks this weekend. If the car doesn't overheat, that means the car isn't built for small tracks.

[persian54]

Originally Posted by wwjd15

Thanks for the advice. I'm going to two different tracks this weekend. If the car doesn't overheat, that means the car isn't built for small tracks.

Keep us posted

and dude I'm telling you, you're just too fast of a driver

[ShadeD1]

I had the same issue this weekend at MSR Cresson TX. I got the overheating message towards the end of 3 of my sessions and had to back off for the last lap or 2.

[wwjd15]

Originally Posted by persian54

Keep us posted

and dude I'm telling you, you're just too fast of a driver

Overheated whole weekend long again. Even I was in 85F, the car overheated in less than 4 laps at Chuckwalla. Hopelessly overheating... Engine oil cooler, tranny oil cooler, and powersteering cooler are on the top of the next move now.

[bigjae1976]

I wonder what the root issue to the overheating is. Isn't the DCT cooler on the right side duct? That would kill the option of using that to direct air somewhere. I don't see many options to increase air flow across the radiators.

Do we realy need to upgrade the engine oil, coolant, tranny, AND p/s coolers?

The fake duct in the hood in the right side...wonder if that could be used to direct air somewhere.

[constantin]

Originally Posted by wwjd15

Overheated whole weekend long again. Even I was in 85F, the car overheated in less than 4 laps at Chuckwalla. Hopelessly overheating... Engine oil cooler, tranny oil cooler, and powersteering cooler are on the top of the next move now.

Had the same issues at Chuckwalla (100F)on Sunday. Once I changed my driving style (shift before 7k) it went away.

[constantin]

I am wondering if water wetter is better than OEM coolant. Anyone?

I'm going to change oil, clean filter, radiator etc and see what happens at Buttonwillow.

[Jeff_DML]

Originally Posted by constantin

Had the same issues at Chuckwalla (100F)on Sunday. Once I changed my driving style (shift before 7k) it went away.

what?? might as well drive a 328 then

[constantin]

cleaned air filter and radiator, no more over heating.