Cluster temp gauge not matching live data

[rantarM3]

Anyone know what temp the stock oil thermostat is supposed to open? I drove my car in 86+ degree weather yesterday and the display temp was at 210. But when I got home to do my oil change the oil cooler was cold to the touch (radiator was warm). I'll retest again today but am now concerned the oil t-stat is out.

[Scharbag]

Originally Posted by Scharbag

The S65 engine in the E90/E92/E93 M3 has an internal thermostat that limits the amount of oil that flows into the cooler, even when warm! This thermostat is closed when the engine is cold so that the oil warms up quicker. But even at operating temp the thermostat does not open all the way! Or worse, can be stuck closed. E9X M3 owners who have experienced high oil temps at the track often don't have an explanation or solution - until now.

This Oil Cooler Diverter Valve quickly remedies this issue by making the cooler full-flow. It diverts all oil through the cooler and lines for maximum cooling strategy. This will typically bring down stubborn oil temps 30+ degrees on tracked engines with the stock cooler. Once the housing is removed this is a quick 5 minute install into the factory S65 oil filter housing. This is not recommended for street cars without the addition of a performance inline thermostat. Drive conservatively and allow extra time for the oil to reach optimal temp (>150 degrees).

Includes diverter valve and installation instructions. The oil filter housing does not need to be removed from the engine, however access requires removing several items from the front of the engine - belt, fan, and power steering pump. This also provides a good opportunity for checking the oil filter housing seal for leaks.

Seems doable in the car... But is it really an issue to not have the performance T-Stat? And where does one get this unicorn inline t-stat?

Cheers,

Anyone have any thoughts on the above?

[jvictormp]

Originally Posted by Scharbag

The S65 engine in the E90/E92/E93 M3 has an internal thermostat that limits the amount of oil that flows into the cooler, even when warm! This thermostat is closed when the engine is cold so that the oil warms up quicker. But even at operating temp the thermostat does not open all the way! Or worse, can be stuck closed. E9X M3 owners who have experienced high oil temps at the track often don't have an explanation or solution - until now.

This Oil Cooler Diverter Valve quickly remedies this issue by making the cooler full-flow. It diverts all oil through the cooler and lines for maximum cooling strategy. This will typically bring down stubborn oil temps 30+ degrees on tracked engines with the stock cooler. Once the housing is removed this is a quick 5 minute install into the factory S65 oil filter housing. This is not recommended for street cars without the addition of a performance inline thermostat. Drive conservatively and allow extra time for the oil to reach optimal temp (>150 degrees).

Includes diverter valve and installation instructions. The oil filter housing does not need to be removed from the engine, however access requires removing several items from the front of the engine - belt, fan, and power steering pump. This also provides a good opportunity for checking the oil filter housing seal for leaks.

Seems doable in the car... But is it really an issue to not have the performance T-Stat? And where does one get this unicorn inline t-stat?

Cheers,

I don't know if that is your question, but.

If you put your coolant always at full flow, your oil temperature will drop too much when you don't push the car hard, and when pushing hard, oil will take longer to get to the optimal temperature.

That's a problem, because your car will always run outside the optimal oil temperature, and the lubrication may not be enough.

The original t-stat was put in there to solve that problem.

Edit:
What is being said above is that the original t-stat doesn't allow full flow even at the maximum opening. So a bypass line with that capacity would solve that flow problem, but even that way it would need a t-stat that supports that full flow too.