FM oil cooler

greenMachine · Postby **greenMachine** » Fri Mar 20, 2015 9:56 pm

Dweezle wrote:I think my temp issue is due to the near enough 8000rpm. If I keep it below 7400 I don't seem to get anywhere near as high oil temp.

Have a look at your dyno chart, and see how much power you are leaving on the table with those 600rpm, that would illustrate what I have been saying about the power producing the heat.

Apu wrote:I don't know how much the radiator / oil cooler combo costs, but my guess is "not cheap". So if you get a hole in one, you'd effectively be replacing three items.

There is more than one way of skinning that cat ... :wink:

madjak wrote:Temperature from shearing the oil (friction).

I have heard of this, but would appreciate some reference for its contribution to heat load in the oil. I need convincing that this would be significant in comparison to the heat from the combustion process.

Thanks everyone for a very informative and constructive discussion.

:mrgreen:

Magpie · Postby **Magpie** » Fri Mar 20, 2015 10:32 pm

This has the EGT included and its increases/decreases are linked to RPM (however this is not shown). The scale of the RPM makes it difficult to see the EGTs.

Again the oil temp starts to drop on the cool down lap, however the engine bay temp keeps creeping up (blue line). In addition the EGT starts to drop because the RPM's have dropped due to the cool down lap. Water again is stable.

Red - Oil Temp
Green - Water temp
Blue - Engine bay temp
Olive - Ambient temp
Orange - EGT (no. 4 cyl)
Grey - Speed

QR TA RND 2 by Eipeip, on Flickr

madjak · Postby **madjak** » Sat Mar 21, 2015 11:44 am

I think the evidence of the temperature contribution of oil shearing can be seen in Magpies logs. If the oil was being heated only by the block and head the oil temp would track similarly to the engine and water temps. Maybe it would be delayed a little due to it's specific heat, ie it takes more energy for it to gain or loose temp. It may also be at a slightly different temp, probably lower as the heat from combustion is being generated in the head and block where all the water coolant is located.

If you think of oil shearing as replacing friction. Instead of metal rubbing on metal in the bearings there are layers upon layers of oil molecules being rolled over each other. The speed and pressure the oil is being sheared at generates lots of heat. Its kind of hard to imagine the forces involved but they are very high and fast. We all know what happens if there is no oil there. So oil shearing heat is much less than friction heat would be.

If you could design a crank bearing that could use magnets to levitate the rods and run the engine in vacuum, there would be no friction heat at all. Of course the forces involved are far too large for this to work.

In the case of Magpies system, I think the heat generated by the oil shearing alone is well over 30 degrees. It could almost be half the the total heat energy given that the oil cooler will be more effective at higher temps.

Magpie · Postby **Magpie** » Sat Mar 21, 2015 1:36 pm

Madjack is on the right path, the oil has potential kinetic energy. As the oil heats the molecules become agitated and this causes more heat. All the parts of an engine have the ability to absord some much heat, the oil (and waters) job is to transfer the heat to the radiator(s) so that the liquid can be cooled and reintroduced to absorb more heat (heat transfer).

The second law of thermodynamics explains it best, heat flows from hot to cold and never the other way around! The oil/water needs to be cooled to the point of being able to effect the heat transfer from the engine parts. As mentioned as you heat oil its own kinetic energy adds to the heat process. But this is where the properties of the oil come into play, some oils will hold their structure longer (withstand a higher heat) than others and therfore able to absord move heat.

The key is picking the right oil for the application it will be used in. Further the cooling requirements need to be matched to how much potential heat needs to be transfered. As discussed cooling the all too much creates other problems so a thermostat should be used in any application. An engine that operates at high RPM all the time will need a much different solution to one that is in stop start traffic.

My car (since the new engine) has always used HKS Super racing 10w55 which has a max oil temp of 150 degC .

A good test would be to try some different oils and try and replicate similar conditions and see what the change in temps are.

Such a simple question has resulted in (I think) a good rounded discussion.

Magpie · Postby **Magpie** » Sun Mar 22, 2015 11:12 am

Have a read of this article http://www.ricardo.com/PageFiles/35412/calculationofFrictioninHighPerformanceEngines.pdf

Dweezle · Postby **Dweezle** » Sat Mar 28, 2015 6:04 pm

Quick question.
Are any of you running a mocal thermo sandwich plate or similar to feed the cooler ??

If so how, how are you getting oil Temps?
These seem to not have sensor ports on them?

Sent from my SM-N9005 using Tapatalk

sailaholic · Postby **sailaholic** » Sat Mar 28, 2015 6:41 pm

The standard mocal ones don't, I thought it was an optional model though when I looked direct on the mocal site . The grex / gready do.

Sent from my iPhone using Tapatalk

Postby **NitroDann** » Sat Mar 28, 2015 6:52 pm

Drill and tap anywhere between the last external part and the main oil gallery into the crank.

Dann

Magpie · Postby **Magpie** » Sat Mar 28, 2015 7:31 pm

I have a remote mount filter.

Engine Bay , on Flickr

Lokiel · Postby **Lokiel** » Sun Mar 29, 2015 9:53 am

sailaholic wrote:The standard mocal ones don't, I thought it was an optional model though when I looked direct on the mocal site . The grex / gready do.
:

WARNING (modified quote from my build thread):

The "problem" with the Trust/Greddy blocks is that they use 1/8" BSPT-28 (British Standard Pipe Thread) sensor fittings whereas most sensor fittings use the US-standard 1/8" NPT-27 (National Pipe Thread) - this probably explains why not many people have used the Trust/Greddy blocks in the US since NPT fittings are the standard.

NPT threads are tapered and are the standard in the US. BSPT fittings, referred to as "PT fittings" in Japan, are used in England and Japan - Trust/Greddy is a Japanese company. Because of the different thread sizes (28 vs 27) you cannot simply tap from one to the other and you need to use an adaptor (Note: 1/8" BSP-28 male barbs can be screwed into 1/8" NPT-27 female sockets but it is a very loose fitting and definitely NOT airtight - don't do it!).

I'm using the 1/8" NPT Female -> 1/8" BSPT Male brass adaptor to mount the PLX Oil Pressure sensor and have drilled-out the Trust/Greddy M18 aluminium plug and tapped it with a 1/8" NPT-27 tap for the PLX Oil Temperature sensor.

They're a great block but make sure you get BSPT-28 sensors or do what I did to fit the NPT-27 sensors.

Dweezle · Postby **Dweezle** » Mon Mar 30, 2015 12:20 pm

NitroDann wrote:Drill and tap anywhere between the last external part and the main oil gallery into the crank.

Sorry, so do you mean you can drill and tap on the actual sandwich plate ?

Magpie, love the pic.
Your oil pressure sensor. Is that mounted to a 90 degree fitting ??

Thanks all for the info.
Yeah getting correct sized fittings is a big plus.

such a simple thing but still confusing for me.

Sent from my SM-N9005 using Tapatalk

madjak · Postby **madjak** » Mon Mar 30, 2015 12:29 pm

I just ordered an inline male -10AN to female -10AN fitting that has an 1/8 NPT port for a sensor. I already have a sandwich plate with two ports which currently have the stock oil pressure sensor, and an Autometer temp gauge. I've ordered a cheap ebay oil pressure sensor that outputs a linear 0-5v signal for the ECU that will go into the inline fitting.

This is probably the easiest and cheapest way to install sensors as long as you already have an oil cooler

Magpie · Postby **Magpie** » Mon Mar 30, 2015 12:58 pm

Dweezle yes it is a 90° fitting.

If at all possible mount your sensors to the body and not the engine so as to reduce potential fatigue due to vibration. At the moment I still have the Innovate oil pressure sensor where the stock one goes. This will be blanked off very soon.

Postby **NitroDann** » Mon Mar 30, 2015 1:08 pm

Yeah dude. Drill and tap the main gallery on the block between the oil reentry and the crank for all I care. This is what Mazda did for the OEM gauge.

Dann