More Rear Mount Oil Cooler Questions, Setrab Setup Options

[BeatNavy]

I'm trying to nail down why I'm having oil cooler issues. Specifically, I've blown two sandwich plate adapter seals in the same place / manner. In addition, during my test drives I wasn't necessarily thrilled with the temp drop I was seeing.

First, I'm running the Setrab oil cooler and Setrab sandwich plate adapter. Anyone else running the Setrab sandwich plate adapter without any issues? I know I'm not the ONLY one, but how many people run this as opposed to something like the Mocal setup?

Second, when I contacted Pegasus Racing to order more seals, I spoke to the tech guy who gave me some food for thought. The most interesting thing was he said the oil cooler needs to be mounted with the inlet and outlet ports facing up, otherwise the cooler won't fill up all the way and you won't get ideal (or any) cooling.

Here's my setup with it angled somewhat down for what I hoped was good airflow: http://www.914world.com/bbs2/index.php?s=&...t&p=2826235

Essentially he says the oil takes "the path of least resistance" which could largely be from the inlet port to the outlet port using few of the cooling rows. I assumed the pressure would fill the cooler, but I can see what he's saying. Any thoughts on that? If that's the case, I really need to completely redo my mounting setup and plumbing.

[GregAmy]

Aren't the heat exchangers already a heat shield for the headers? If air is running through them, the exterior should stay pretty cool.

Mine are horribly hot, you can't even get your hands near them.

There's a TON of heat stagnating under the backside of these cars.

This is on mine. It's now covered in adhesive-backed reflective insulation.

It's finally stabilizing the temps around 215-220 (in the line exiting the cooler) on 80+ days.

[Olympic 914]

Aren't the heat exchangers already a heat shield for the headers? If air is running through them, the exterior should stay pretty cool.

Mine are horribly hot, you can't even get your hands near them.

There's a TON of heat stagnating under the backside of these cars.

This is on mine. It's now covered in adhesive-backed reflective insulation.

It's finally stabilizing the temps around 215-220 (in the line exiting the cooler) on 80+ days.

Do you still have the original oil cooler in place? No gauge sender in the taco plate?

I guess it depends where you are reading the temp.

As I understand the oil flow -

(1) its picked up from the sump,

(2) through oil pump then to the oil filter


(3) through the stock oil cooler

(4) on to the bearings etc. through the oil galley.

If you are reading the temp inline after the aux cooler your oil temp should drop some more after going through the stock cooler, before going into the engine.

Using a sandwich adapter, after the oil filter the oil goes to the aux cooler then back through the stock cooler to dissipate more heat before going to the bearings etc.

By having the sender for the temp gauge in the taco plate you are reading the oil temp after it has gone through the engine and lubricated/cooled it.

[GregAmy]

As I understand the oil flow -

At the risk of diverting Rob's thread...you got me to thinking more about this.

My combo gauge and Mainely dipstick agree on temperature, so I'm pretty confident of that. I've rechecked the calibration on the R-T sensor and I have a long history of their sensors in my race cars, so I'm confident of it as well.

But here's the thing I cannot explain.

As noted I'm using the Tangerine block/thermostat and external oil cooler, and measuring the oil temperature on the outlet line of the cooler.

And yet...the temperature is the same or very similar as that in the sump.

Chris Foley and I have gone back and forth on this, and I'm very very confident that we actually have it in the cooler exit line.

But this makes no sense.

I've checked and rechecked the oil cooler lines, and rechecked the sensor calibration.

So this means that either my temp sensor is wrong, the cooler is doing nothing, and/or the ports on the thermostat block aren't what we think they are (but Chris built the block so I'm pretty sure he knows which way they go).

One thing for sure is that between adding the cooler, adding a fan to it, and ducting air to it, my oil temps are stabilizing around 215F on the Mainely dipstick at highway cruise with the fan on 100% of the time.

Everything else is up for grabs.

[BeatNavy]

At the risk of diverting Rob's thread...you got me to thinking more about this.

Greg -- Not diverting at all. I'm finding this interesting and useful.

I've never really had a reason to doubt my oil gauge and sender match, but I would like to correlate / validate if possible. I've got a laser thermometer, but it's hard to tell how best to use that to get something accurate. Get the car up to temp, put it up on the lift as soon as possible while warm, and hit the sump plate with the laser thermo? I've tried reaching under the car, even while it's running, but I'm not convinced I'm getting something accurate. The numbers I AM getting are lower than the gauge (my sender is at the taco plate location).

I also have a Mainely by Design dipstick thermo, but for some reason it won't fit in the oil filler tube that's on this case (IMG:style_emoticons/default/blink.gif)

I've even thought about taping a cooking thermometer underneath the trunk just to get some idea what ambient temps are under there to see what heat transfer potential there is without adding ducting. I think you described it, Greg, as a lot of hot air "stagnating" under there. Sounds about right.