Oil cooler in feed or return

[anonymous-user]

The initial message was deleted from this topic on 27 February 2025 at 16:43

[GreenV8S]

If it's getting over cooling in its current location then I don't see any incentive to try to optimise the layout to improve cooling.

[stevieturbo]

Just remove the cooler ?

[GreenV8S]

AceRockatansky said:

Well the idea is to reduce thermostat opening on the feed.

Still not following you. What are you trying to achieve?

[Haltamer]

Cardboard over the heat exchanger.

Trim it down until you've got just the right amount of cooling.

Problem solved, no plumbing needed

[Tony1963]

Will it still over-cool in the higher ambient temperatures of summer?

Yes, fit a thermostat.

[richhead]

AceRockatansky said:

So where do people plumb their oil cooler? Seen arguments for the various positions.

Currently getting too much over cooling, so fitting a canton thermostat. Engine is dry sumped.

Oil cooler is currently fitted on the return to the tank, but figure I'll get more heat on the feed.

coolers are most offten on the return to prevent heat build up in the tank. If you have too much cooling then as said either use rad blanking or a thermostat,
Or is the cooler too big?
In racing we look for around 110-120 deg, although alot of modern oils are happy at higher temps now.
Eitherway you want it to get over 100 regularly to remove moisture

[Chris32345]

How's it getting fed oil?

You could restrict the amount of oil flowing through it as well

But blanks part of the fins would be my fire try

[LastPoster]

In my dry sumped rally car with the tank in the boot I never needed an oil cooler at all. All that pipe (twin scavenge and return pipes) must have given off so much of the heat anyway. Link it out and see how it copes.

[richhead]

AceRockatansky said:

richhead said:

AceRockatansky said:

So where do people plumb their oil cooler? Seen arguments for the various positions.

Currently getting too much over cooling, so fitting a canton thermostat. Engine is dry sumped.

Oil cooler is currently fitted on the return to the tank, but figure I'll get more heat on the feed.

coolers are most offten on the return to prevent heat build up in the tank. If you have too much cooling then as said either use rad blanking or a thermostat,
Or is the cooler too big?
In racing we look for around 110-120 deg, although alot of modern oils are happy at higher temps now.
Eitherway you want it to get over 100 regularly to remove moisture

I've gone for the canton stat as it's straight through when closed with minimal restriction and opens at 215 degrees F. Tank is in the front, but the oil cooler is actually quite large and difficult to block off but has been running successfully for a few years by the previous owner, I assume in warmer weather.

I'll put it in the return as before.

That temp sounds about right.
reminds me of my first time engineering a car in the us, the brake guy handed me a slip of paper with the brake temps on after a pit stop, i shxt a brick, as the temps were in the thousands, bloody gave it to me in f not c.

[E-bmw]

IIRC oil temp should be over 80 deg C to ensure water entrained can evaporate.

[540TORQUES]

E-bmw said:

IIRC oil temp should be over 80 deg C to ensure water entrained can evaporate.

80+ is what you are looking for, it's not just water content you are burning off, which is minimal, it's unburned fuel contaminants that dilute the oil over time that need to be evaporated off.

It's always nice to have circa 10 degrees higher oil temp than water, with water around 80-90 degrees on a conventional engine. Modern racecars can be run hotter mainly for aero benefits.

Oil coolers in the scavenge return have benefits, they help deairate the oil before it reaches the dry sump tank and you have no pressure drop in the oil fed to the bearings. The cooler also sees much lower pressure, so is less likely to fail, if you have a viscous cold oil and a high pressure oil system, a cooler in the pressure side can burst.

[E-bmw]

540TORQUES said:

E-bmw said:

IIRC oil temp should be over 80 deg C to ensure water entrained can evaporate.

80+ is what you are looking for, it's not just water content you are burning off, which is minimal, it's unburned fuel contaminants that dilute the oil over time that need to be evaporated off.

Hence why I said over 80 deg C.