More Rear Mount Oil Cooler Questions, Setrab Setup Options

[dirk2056]

What about a different approach does the horizontal cooling fan set-up from Tangerine cool the engine better and do not need additional oil cooler. I like you have external cooler but have had about same results.

[GregAmy]

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 as a lot of hot air "stagnating" under there.

Really like this idea. (IMG:style_emoticons/default/idea.gif)

I may try this myself, using a WiFi endoscope to view the temperature changes.

It would be interesting to others results.

Bluetooth wireless BBQ thermometer to your phone...

[Olympic 914]

I did this yesterday, with the thermometer and Wifi endoscope.

I opened a new thread for this

http://www.914world.com/bbs2/index.php?showtopic=347282

And also linked back to here from it. It may help in future searches.

Can't have too much oil cooler info for these engines.

[GregAmy]

(IMG:style_emoticons/default/beerchug.gif)

[Frank S]

Rob, next time I'm driving I can shoot the IR onto the oil change and taco plates and see how well they correlate to the dipstick.

I like the idea of a cooking thermo to check air temps under there.


Edit: as a somewhat-related aside, I'm also surprised at the enginecompartment/air intake temps on my car. I've got the Intake Air Temp sensor inserted into the bottom of the stock D-Jet air cleaner, and I'm regularly seeing IATs of 130F+ at cruise, and that's with the rain tray removed...so that's all going into the intake for cylinder/head cooling. And that's with all new seals all around the engine tin...

Hi Greg,
I had experienced the same heat soak problem with tha MAT Sensor mounted in the original D-Jet position (plenum). The plenum is physicaly conected to the engine case and has a huge surface are which is not ventilated well close to the engine case, seeing alot of radiation. During normal driving with CHT of 320°F and oil temps around 215°F MAT was around 149°F. With the open element sender mounted inside the snorkel I was able to reduce the MAT reading down to 118°F under the same conditions mentioned above. This was meassured with the raintray mounted at ambient temp of 83°F.

I think you are still meassuring at a not optimal spot or your MAT Sensor is not an open element sensor.

Regards,
Frank

[GregAmy]

0, 01:10 PM' post='2834051']I had experienced the same heat soak problem with tha MAT Sensor mounted in the original D-Jet position (plenum).

[/img]
Thanks, Frank! Yeah, my original design had the IAT, an open-element Delphi, mounted on an adapter plate where the D-Jet CSV was. It didn't take long for me to realize it was a heat soak issue. So a few weeks ago I mounted it on the underside of the stock air filter, inline with the snorkel.

Surprisingly, I didn't see a ton of difference, it went from around 140 down to around 130.

I routed some flexible brake cooling hose from the D-Jet snorkel to the underside of the engine grill yesterday and got it down to 105F, 80F ambient.

I'm actually wondering if I should consider installing a draw-down fan on the underside of the engine decklid.

(IMG:http://www.914world.com/bbs2/uploads_offsite/cdn11.bigcommerce.com-15565-1594834257.1.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-15565-1594736262.jpg)

[Frank S]

0, 01:10 PM' post='2834051']I had experienced the same heat soak problem with tha MAT Sensor mounted in the original D-Jet position (plenum).

[/img]
Thanks, Frank! Yeah, my original design had the IAT, an open-element Delphi, mounted on an adapter plate where the D-Jet CSV was. It didn't take long for me to realize it was a heat soak issue. So a few weeks ago I mounted it on the underside of the stock air filter, inline with the snorkel.

Surprisingly, I didn't see a ton of difference, it went from around 140 down to around 130.

I routed some flexible brake cooling hose from the D-Jet snorkel to the underside of the engine grill yesterday and got it down to 105F, 80F ambient.

I'm actually wondering if I should consider installing a draw-down fan on the underside of the engine decklid.

(IMG:http://www.914world.com/bbs2/uploads_offsite/cdn11.bigcommerce.com-15565-1594834257.1.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-15565-1594736262.jpg)

I have my sensor mounted from the top, but the sensor element is twice as long as yours and sticking in the middle of the airstream. Unfortunately I don't have a pic of the sender just one with the sensor mounted.




I see your sensor is also a open element sensor, so I really wonder whay we get so different readings...

[GregAmy]

I have several oddball things going on, like an IGN4-VW coil that starts cutting out after 30-40 minutes. I attribute that to something different/wrong with my engine/car.

I may try adhesive-backed reflective insulation on the underside of my airbox.

[Frank S]

I have several oddball things going on, like an IGN4-VW coil that starts cutting out after 30-40 minutes. I attribute that to something different/wrong with my engine/car.

I may try adhesive-backed reflective insulation on the underside of my airbox.

Is it the Ignition coil cutting out or do you struggle with sync loss problems due to too high temps at the Crank Pic-Up Sensor?
Do you have a tooth log?

[GregAmy]

Is it the Ignition coil cutting out or do you struggle with sync loss problems due to too high temps at the Crank Pic-Up Sensor?
Do you have a tooth log?

Very confident it's not synch loss; I'm not logging any synch loss at all except when I "burn" with the car running.

Symptoms are stumbles and the AFR momentarily pegs full lean. I replaced the coil with a new one and it briefly got a lot better but it's starting to come back. Usually runs smooth for a half hour, then very light stumbles til about 45 minutes, then very hard stumbles. Died on me yesterday, I had to coast to a stop. Top of the coil was 184F via IR.

I've been told this coil really likes big wires for power and ground, but I'm using AWG14 for both, didn't seem to affect anything.

I'm thinking it's just getting too hot in the location I have it (on top of where the disty was).

We can discuss in your Megasquirt thread, I need some ideas.

[VaccaRabite]

That's really clean. Super impressive. I need to do better cable management on my engine.

Zach

[GregAmy]

Thanks. I think the vast majority of my brain power for the whole project was working through the harness/wiring design and actually sitting down at the engine stand and wiring it up. It was one of those "Zen things" where I sat with beer and Pandora and just worked on it a bit at a time. All the design details are in Part 9 (10?) of the write-up I did. I even drew it up on cardboard so I can replicate it relatively easily if I had to make another (which I may consider doing for the race car).

https://tgadrivel.blogspot.com/2020/03/on-m...914-part-1.html

One design priority was to have quick connects and the ability to easily remove it. I did exactly that tonight to change the coil ground to 12AWG and it took me less than a minute to have it sitting on my work bench.

[Montreal914]

(IMG:style_emoticons/default/popcorn[1].gif) on all topics (IMG:style_emoticons/default/smile.gif)

[Frank S]

Is it the Ignition coil cutting out or do you struggle with sync loss problems due to too high temps at the Crank Pic-Up Sensor?
Do you have a tooth log?

Very confident it's not synch loss; I'm not logging any synch loss at all except when I "burn" with the car running.

Symptoms are stumbles and the AFR momentarily pegs full lean. I replaced the coil with a new one and it briefly got a lot better but it's starting to come back. Usually runs smooth for a half hour, then very light stumbles til about 45 minutes, then very hard stumbles. Died on me yesterday, I had to coast to a stop. Top of the coil was 184F via IR.

I've been told this coil really likes big wires for power and ground, but I'm using AWG14 for both, didn't seem to affect anything.

I'm thinking it's just getting too hot in the location I have it (on top of where the disty was).

We can discuss in your Megasquirt thread, I need some ideas.

Hi Greg, would be fine with me. But I also think it's a temperature related issue. But after I checked the other post with the underfloor temp meassurements, which is great, I think there is a problem with the engine tune. I'm running much cooler oil and head temps without an additional oil cooler (2056).
But let's discuss this at a different place as it would be misleading here since Rob is running a lager displacement engine which requires additional oil cooling.

[stownsen914]

Very interesting re: the temp. under the back of the car. 120-140 degrees is not as hot as I would have expected. Can't argue with data. The second challenge with the cooler back there is limited air flow.

[dirk2056]

Cooling test under car with and w/out fans, Installed (2) 4" fans under trunk each side of transmission. Oil cooler was not installed for test, oil temp was 220 out side temp 90. Rough numbers fans removed 11 deg under car and no affect on oil temp.
Don't look at oil pressure numbers turned off car to take pictures.
Next test will be with oil cooler installed?? Is 220 oil temp acceptable?
2056 engine with duel 40 carbs

[Krieger]

220* is a good oil temperature

[GregAmy]

Hi Greg, would be fine with me. But I also think it's a temperature related issue.

Just a quick follow up: I think you're spot-on. Last week I move the coil to on top of the cooling fan (basically tye-wrapped it there) and drove it an hour with zero stumbles. Top of the coil was 94F, area on the block where it was mounted was 185F.

I need to work on a relocate bracket.

I'm also going to gold-reflect the bottom of the plenum and air filter box. Thoughts on any good phenolic washers/isolators where the plenum bolts to the case?

And, next time I've got the engine tin off I'm likely to gold-reflect its underside as well.

We've been living with a ton of excess heat on the top these engines and were never really worried about it.

[BeatNavy]

Just a follow up on this thread. Did about 600 miles this past weekend up to the NE gathering in PA. I sprung no major oil leaks. That is a good thing. I still have some oil drips to deal with, including (I think) on the front main and probably gear oil at the gear selector (need new gasket for that, I think). So while I left my mark everywhere (IMG:style_emoticons/default/shades.gif) I didn't take an absolute dump anywhere.

Oil temps were really good all weekend (e.g. 210 to 220+) as long as the car was moving fast enough to displace that hot air underneath. This generally meant 55 mph and above. The Saturday joy ride with the group was a bit more difficult, as we were routinely below 50 mph and also stopped a number of times to gather up lost sheep. As soon as you stop the fan really can't do much to pull cool air in and cool the oil, particularly when ambient temps are 90 degrees.

For now I think I'm good, although I'm going to look into ways to bring cooler air to and through the cooler.