A MUST READ for Oil Temps for Tracking

[12-motorsports]

Buckle up because this is a long read BUT worth it if you are serious about tracking your Gen5 Camaro!

Wanted to put this together because all of the questions/comments posted about engine and transmission temperatures and their concerns when running on the track or under heavy loads. I tackled the problem in a different manner providing “end results” with empirical data to support my efforts.

First of all, I track my 13’ 2SS L99/A6 on road courses e.g. VIR, Watkins Glen, etc. I normally run with HPD clubs that run 30 minute sessions at a time. My car has been upgraded with 1 7/8” Kooks headers, high flow CATs, QTP exhaust cutouts (for track usage), engine tuned, cold air intake, etc. pushing 385 RWHP. My first few track days, following these upgrades, had me concerned with engine oil and transmission temperatures utilizing the “factory” cluster gauges. I immediately turned the Camaro5 forums to see what others out there experienced and/or did about the concerns with the temperatures. I found A LOT of talk about the concerns and ideas to address them. However, I was not totally satisfied in my findings. I am an engineer at heart and decided to take on this little challenge once and for all and try my best to fully research the problem and share my findings and recommendations.

During my first few track days it was 90 degrees and I quickly found the engine and transmission producing some extremely high temperatures accordingly to the factory gauges. I grew up in the pre-synthetic oil era, playing with cars all of my life and was of the mindset mineral oil base oils cannot handle temperatures above 225 degrees for sustained periods of time without serious break down. So, when my gauges displayed 300 plus for engine oil and transmission I started to worry about damaging components and/or catastrophic failure. That is when I turned my attention to getting those temperatures down to a more “normal” and acceptable range under high stress while running on road courses.

Starting with the automatic transmission, I shopped online for a cooler solution because many others on this site posted a ton of suggestions for a “good” transmission cooler. Of course there is one solution which is the most simplistic to install and that is the ADM Transmission Cooler kit for Gen5 Camaros. The kit comes complete with everything needed to install the cooler – including hoses and fittings to marry up with factory ones WITHOUT any modifications. However, for those who are serious about setting up their car for various applications, the better route would be a solution that allows more flexibility in configuration considering application, future growth, etc. I ended up getting the ADM kit for the mounts and the cooler itself while not using the hoses and connections. I then purchased AN hoses and connectors because I wanted the flexibility and reliability of AN hoses considering I am working towards a full blown race car down the road. Additionally, I added a temperature controlled fan to the back of the cooler because when you run road courses you are not always up to speed producing enough “air” to provide the maximum heat exchange.

It was time to tackle the engine oil cooler. This is where I conducted a lot of research because I wanted to properly “engineer” a solution that would allow the flexibility to upgrade/grow HP numbers without changing out the oil cooler again – saving money in the long run. I found several sources online but ended up calling Fluidyne and talking to the owner and lead designer. Fluidyne is the leader in designing coolers for NASCAR and other racing applications.

During my discussions with Fluidyne, some very important points were discussed about picking oil coolers. One of them was obviously surface area, the more area contact of the cooling medium (air in our case) with the channels carrying fluid the better. HOWEVER, there is a happy medium because bigger coolers (mainly length) introduces flow restriction causing you to lose valuable oil pressure. The best way to think about this is to have shorter distance flow with many more channels carrying the fluid (for those who understand Ohms law think of this as adding resistors in parallel). Given this, our Gen5 Camaros have limited real estate up front that is exposed to “clean” cool air before hitting the radiator. Speaking of which, one should consider not blocking off too much “clean air” to the radiator otherwise you will introduce another challenge of higher coolant temperatures. Another factor to consider is the “directional” flow of coolers. For example, the stock Camaro radiator is a “vertical” flow cooler – meaning the fluid runs up/down. Fluidyne and for that matter most other fluid coolers are “horizontal” flow – meaning the fluid runs left/right. Therefore, if you place a horizontal flow cooler directly in front of the factory radiator you will have inefficiencies of air flow between the two because the air has to change directions causing turbulence and therefore less efficient heat transfer (i.e. cooling the medium inside) in the radiator/cooler.

Lastly, for monitoring temperatures it is best to measure the fluid temperature on the “out” of the cooler so you have at true measure of the efficiency of the cooler. In our particular case, this will tell us our engine oil temperature before it reaches the first bearing in the engine.

The typical LS engine’s oil pump has a capacity of ~14 GPM. However, most of that oil is not utilized and simply dumped back into the sump. That constant churn does not allow proper cooling and not to mention the pump action of compression introduces a temperature increase to the oil and over time increases like a differential equation. So, given all that including running your car nearly at full throttle, most of the time on the track, along with long tube headers (near the oil pan) it all adds up to A LOT OF HEAT inside the engine oil.

If you have a factory engine oil temperature gauge in your Gen5 Camaro, the sensor for that gauge is located on the right-hand side of the oil pan. First and foremost, I would like to set the story straight because there are some posts of “mis-information” on this site stating that the oil temperature is “computed” vice measured. I have confirmed that the oil temperature sensor in the oil pan ACTUALLY measures the oil temperature inside the pan. I also verified the accuracy of the engine oil temperature gauge. By purchasing another sensor and using a water along with another temperature monitoring device, the factory gauge is fairly accurate with what I believe is within +/- 5 degrees – again dispelling rumors out there that the factory gauge is inaccurate. Remember this is the temperature of the engine oil in the pan ONLY.

Now, with the above statement we need to discuss the “actual” engine oil temperature prior to reaching the first bearing in a “stock” LS3/L99 engine. Unfortunately GM did not design the Gen5 Camaro with that in mind. Again, this site has a lot of discussions about the factory oil cooler on the left-hand side of the engine. The factory oil cooler utilizes engine coolant to cool the engine oil, but most discussions state it does not work well. Given what I have discovered, there is really NO way of ruling this a fact or not because we have no way of measuring the oil temperature after it leaves the heat exchanger (that is the proper term for the factory oil cooler).

Considering basic physics/chemistry, we cannot have 100% heat transfer in a heat exchanger AND more importantly the coolest possible output temperature in our application cannot be lower than the cooling medium itself (unless we use principles of refrigeration in which we are not here). With that stated, the cooling medium in our application (factory engine oil cooler) uses the engine coolant. Our cars’ factory thermostat keeps the coolant in the engine block ~190 degrees under normal operating conditions. Therefore, we now know our engine oil cannot get below that temperature. Yes, there is additional heat loss around the exchanger because of the metal casing but that is minor considering the other heat sources around the area e.g. headers, engine, etc. My car is a 13’ and it appears that my configuration is a bit different than some of the other postings of prior years. For example, most people mention once they remove the factory heat exchanger they need to remove the “T” in the upper radiator hose. Well, my car does not have that “T” and I have a direct connection to the radiator and engine block – something else to consider when removing the factory cooler on 13’ and newer cars.

Ok moving on, we now know that the engine oil cooler cannot go below ~190 degrees. Additionally, under high engine load we also know the engine coolant temperature rises well over 200 degrees, which will cause the oil temperature coming out of the factory cooler to rise as well. Notice I have not even talked about the cooling capacity of the factory cooler? I have no idea what it is and given it is fairly small in size I bet it is not that much? Therefore, in my books I believe the engine oil coming out of the cooler is too high before it is utilized for lubrication and cooling. Remember engine oil has two main functions, lubrication and cooling engine parts. When oil temperatures are high and the oil thins it loses properties to fulfill these two main ideas. Not to mention when oil is in a bearing it is in a thin like sheet and when the oil properties are stressed with extreme temperatures that sheet can tear – causing metal on metal. That is not good!

Shifting gears to oil now. Mineral based oils have very different properties than today’s synthetic oils. Mineral based oil breaks down easily at higher temperatures and does not like operating under high stress. Hence all car manufactures utilizing full synthetic and/or blend mixes. Synthetic oils have a higher tolerance to operating temperatures. Every oil manufacture/brand has their own specifications/limitations – too many to list here. But for discussion purposes I researched a few and found most quality synthetic oils can operate at extreme temperatures nearing 275 degrees without breaking down. Another valuable property of synthetic oil to consider when talking about “thin sheets” between bearings is that synthetic oils have a much higher tensile strength to break that sheet. That is why racing engine builders’ love using full synthetic oils.

So, if you are going to use your stock engine oil cooler for everyday driving and/or short sprints i.e. drag racing you might be ok to get away with keeping the factory cooler. However, if you are going to track the car you should seriously consider installing an aftermarket engine oil cooler for two primary reasons: cooler oil to the first bearing and more importantly obtain a “true” oil temperature before it enters the oiling system.

During my research and reviewing posts on this site I found many like get the coolant and engine oil temperatures below the “factory” designed range. For example, most think that if you replace the 185 degree thermostat with a 160 degree thermostat your engine will be cooler and will product more horsepower. Well, that is fine and dandy if you have a full-time race car. But if you are running your car as a daily driver and/or need it to pass emissions then you need to keep the 185 thermostat to keep the engine temperature up to ideal conditions for the emission systems to work properly. Not to mention, lower temperatures causes buildup of moisture and sludge inside your engine. If you notice while driving your car in normal conditions the oil temperature is just at or above 212 degrees – hot enough to boil off vapors and moisture inside your engine.

With that said, while designing your engine oil cooler configuration you need to consider regulating the oil temperature for those daily drivers. Fortunately for us who want to use our cars as daily drivers and keep most of the “factory” functionalities, there are a few solutions to regulate engine oil temperatures. I ended up purchasing a thermostat controlled oil cooler adapter from Improved Racing. It regulates the oil temperature at 212 degrees – but note they claim 10% of oil still flows to the cooler even if not above 212 degrees. There are other options such as in-line thermostats if you want a simplistic oil cooler adapter that replaces the factory head exchanger.

Moving on to the oil cooler itself, I researched many coolers from online retailers and found one that best fits my application. I ended up picking one from Jeg’s because I did not want to modify my front end as well as not blocking off too much air flow to the radiator. On the flipside, I wanted a cooler to handle 500 HP because in the future I will be installing a Mast Motorsports head/cam package – which will require a higher cooling capacity to handle the higher heat load. Improved racing had a useful chart to help pick the approximate cooler size for my application. Since it was for a particular brand, I used it as a starting point thinking in terms of surface area. Finally settling on a Jeg’s branded oil cooler that will fit just below the front bumper and at the bottom opening of the grille. The cooler is 15” wide x 4” tall x 3.5” deep.

After obtaining the cooler and engine oil cooler adapter it was time to design the hoses and connectors. Naturally you want to use AN hoses because of the ease of use and reusability of them. Luckily the oil cooler adapter from Improved Racing allows you to pick the AN fitting you are utilizing for your hoses. I chose -10 AN based off the oil ports coming out of the engine adapter is one size above that. By having a slightly bigger hose and connectors, you will have less friction for the flow of oil. Fluid dynamics is complex and not easy to discuss therefore I will keep it simple here. But friction of flow of a medium in a hose depends on many variables such as pressure, friction coefficient of the hose material, length, elevation change, bends, etc. I ended up purchasing a light -10 AN racing hose to mate up with AN connectors on the oil cooler adapter and cooler (note most coolers will require additional adapters e.g. NPT to AN etc).

Moving on to temperature monitoring/sensing both the engine and transmission oil coolers. I ended up with an Aeroforce Interceptor Gauge – again did not want to modify my interior too much with gauges everywhere as I am trying to keep it as a daily driver. The beauty of the Aeroforce gauge is that it hooks up to your OBD2 connector AND has analog inputs for additional sensors such as temperature sensors. With the Interceptor you can chose parameters that you want to monitor and/or cycle through all in one 2 1/6” gauge. I mounted the gauge on the steering column for simple viewing while driving. Additionally, it has an alarm feature in which I have programmed to light up LEDs when I reach optimum RPM so I know when to shift!

The Jeg’s cooler has a port for a temperature sensor (near the “out” port) and for the transmission oil cooler I added an “in-line” adapter on the “out” line of the cooler. For both of these sensors, I used Aeroforce’s 3/8” NPT sensors. Please note I did not address the location of the factory transmission oil temperature sensor as it is internal to the transmission and unsure where it measures the temperature?

After everything was installed, tested, and finally “track” tested, results were successful. I was pleased with the final numbers of the cooled engine and transmission oils especially under a heavy load condition. Below is just a sample set of the numbers so one can see just how different the factory gauges report vs “no-bull” cooled oil temperatures after installing aftermarket coolers. In summary, if you do any type of road racing aftermarket oil coolers is a must to keep those temperature in check!

* ALL TEMPS IN “F” DEGREES

Driving Conditions: Light Load (local) Heavy Load (road racing)
-----------------------------------------------------------------------------------
Ambient Air Temp: 70 78
Max Factory Coolant Temp: ~196 ~218
Max Factory Engine Oil Temp: ~212 ~292
Max Factory Transmission Temp: ~170 ~250
Max Cooled Engine Oil Temp: ~110 ~228
Max Cooled Transmission Oil Temp: ~132 ~178

Please head over to www.facebook.com/12-motorsports for pictures etc.

Enjoy!

Thomas

[X25]

I wish you categorized you're post in a few sub sections to make it easier to read, but thanks for your contribution for sure!

Regarding factory engine oil help gauge, I know for a fact now that it's fake. The sensor is real, but the reported engine oil temp does not use its readings to come up with the oil temp number displayed. Yes, you read that right. In fact, just go ahead and disconnect that oil temp sensor, do a test drive, and enjoy your fake oil temp readings being fed to you despite having that sensor disconnected! Long story short, having a real temp sensor does not prove that readings are not fake. Very weird, I know. It seems that sensor is rather used for engine oil level warning and engine protection mode at very high engine oil temps.

Check this out for more reading on this:
http://www.camaro5.com/forums/showthread.php?t=381050

[X25]

Originally Posted by 12-motorsports

Buckle up because this is a long read BUT worth it if you are serious about tracking your Gen5 Camaro!

....
* ALL TEMPS IN “F” DEGREES

Driving Conditions: Light Load (local) Heavy Load (road racing)
-----------------------------------------------------------------------------------
Ambient Air Temp: 70 78
Max Factory Coolant Temp: ~196 ~218
Max Factory Engine Oil Temp: ~212 ~292
Max Factory Transmission Temp: ~170 ~250
Max Cooled Engine Oil Temp: ~110 ~228
Max Cooled Transmission Oil Temp: ~132 ~178

Please head over to www.facebook.com/12-motorsports for pictures etc.

Enjoy!

Thomas

Did you mean to type 210? 110 would be to low for the engine oil to stay healthy and not accumulate humidity.

Thank you very much for sharing all this information!

[12-motorsports]

As for my car, when you disconnect the engine oil temp sensor the gauge does not read anything and will not move even driving it. When I connected my test sensor and while changing the temperature using water (outside the oil pan) I could change the factory gauge to reflect the reading of the water - verified with another accurate temperature probe.

As for your other question, 110 is correct. Remember the Improved Racing Oil Adapter maintains the oil temp "inside" the engine and only opens up at 212. However, even when the thermostat is closed there is about 10% oil flow to the cooler. Hence a small amount of oil temperature at the oil cooler.

[X25]

I think you could have connected the oil temp sensor to oil coming from the engine block to the cooler, so it would read the correct temp at street, too. What do you think? This was also what was recommended by Improved Racing.

[mlee]

WoW... nice write-up. Half way through but will get back soon.

[hcsi99]

12-Motorsports, Great write up! You said you used -10AN, but the Jegs Cooler says it's -12AN. Did you use reducers for the cooler, or does the cooler come in -10AN, and I just didn't see it?

[12-motorsports]

Originally Posted by X25

I think you could have connected the oil temp sensor to oil coming from the engine block to the cooler, so it would read the correct temp at street, too. What do you think? This was also what was recommended by Improved Racing.

Yes, there are many ways to monitor oil temps i.e. in the sump, before cooled, after cooled, in the engine, etc. But what really matters is the temp of the oil going into the oiling system before the first bearing. That port on the adapter is on the "out" line side which is before the cooler. Oil flow in a LS3 is SUMP->PUMP->FILTER->ADAPTER->OIL SYSTEM therefore you basically are measuring the same oil temperature as the factory gauge taking the temp in the pan. Not to mention using the Improved Racing adapter it must be turned upside down to clear headers and therefore unable to utilize that port.

The Jeg's oil cooler I used was 555-51705 and has -10AN connectors.

[hcsi99]

Maybe I missed it, but what sensor set up are you using for the engine oil cooler? In your picture of the cooler mounted on the car, is it the fitting going in to the bottom of
the cooler?

[X25]

Originally Posted by 12-motorsports

Yes, there are many ways to monitor oil temps i.e. in the sump, before cooled, after cooled, in the engine, etc. But what really matters is the temp of the oil going into the oiling system before the first bearing. That port on the adapter is on the "out" line side which is before the cooler. Oil flow in a LS3 is SUMP->PUMP->FILTER->ADAPTER->OIL SYSTEM therefore you basically are measuring the same oil temperature as the factory gauge taking the temp in the pan. Not to mention using the Improved Racing adapter it must be turned upside down to clear headers and therefore unable to utilize that port.

The Jeg's oil cooler I used was 555-51705 and has -10AN connectors.

Sounds good to me, I want to measure what OEM sensor measures anyway. After all, it is the max temp you hit in the system (right before cooling), which is most important. I honestly also thought about putting gauges on both in and out, but don't want to put any more fittings to the system : )

I am not using the sensor bung on the adapter. I'm rather going to use an inline sensor manifold. From my build thread:
http://www.camaro5.com/forums/showth...86#post8018686

I should have realized this fake gauge issue the day I installed the oil cooler, since the engine oil temp was climbing very fast considering there was no warming aid by the coolant anymore (it was showing wrong temp). Anyhow, lesson learned, moving on. I ordered the following:

• Improved Racing ENV-150 Dual Inline Oil Sensor Manifold Block: This will let me tap into the line oil temp and pressure.
  
  
• Autometer 5286 direct-fit gauge-pod for Camaro: This should provide a good location for the gauges.
  
• Autometer 6348 Oil Temp Gauge
  
  
• Autometer 6327 Oil Pressure Gauge
  
  

[JusticePete]

Nice write up. I will once again tell that straight from GM the gauge is a mathematical model.

From the beginning I have written the oil cooler on the 5th Gen as pre-heater for emissions that does double duty as an oil cooler.

[12-motorsports]

Originally Posted by JusticePete

Nice write up. I will once again tell that straight from GM the gauge is a mathematical model.

From the beginning I have written the oil cooler on the 5th Gen as pre-heater for emissions that does double duty as an oil cooler.

JusticePete - Well I can tell you that on my 13' I can disconnect the oil pan sensor and the gauge will go to full left without any movement - even if I drive it. Furthermore, I purchased another OEM sensor and connected it up while it was in a container of water. I then changed the temperature (from 50 to 212 F) several times up and down the the factory gauge in my car correctly reflected those changes (verified with another temperature probe). When you received word from GM what year was it? Maybe starting back in the G8 and early days of Gen5s it was the case?

Totally agree on the purposes of the OEM oil cooler! Thanks for the reply.

[12-motorsports]

Originally Posted by hcsi99

Maybe I missed it, but what sensor set up are you using for the engine oil cooler? In your picture of the cooler mounted on the car, is it the fitting going in to the bottom of
the cooler?

HSCI99 - Yep, it is at the end of my long write up. Here it is again:

Moving on to temperature monitoring/sensing both the engine and transmission oil coolers. I ended up with an Aeroforce Interceptor Gauge – again did not want to modify my interior too much with gauges everywhere as I am trying to keep it as a daily driver. The beauty of the Aeroforce gauge is that it hooks up to your OBD2 connector AND has analog inputs for additional sensors such as temperature sensors. With the Interceptor you can chose parameters that you want to monitor and/or cycle through all in one 2 1/6” gauge. I mounted the gauge on the steering column for simple viewing while driving. Additionally, it has an alarm feature in which I have programmed to light up LEDs when I reach optimum RPM so I know when to shift!

The Jeg’s cooler has a port for a temperature sensor (near the “out” port) and for the transmission oil cooler I added an “in-line” adapter on the “out” line of the cooler. For both of these sensors, I used Aeroforce’s 3/8” NPT sensors. Please note I did not address the location of the factory transmission oil temperature sensor as it is internal to the transmission and unsure where it measures the temperature?

[JusticePete]

Originally Posted by 12-motorsports

JusticePete - Well I can tell you that on my 13' I can disconnect the oil pan sensor and the gauge will go to full left without any movement - even if I drive it. Furthermore, I purchased another OEM sensor and connected it up while it was in a container of water. I then changed the temperature (from 50 to 212 F) several times up and down the the factory gauge in my car correctly reflected those changes (verified with another temperature probe). When you received word from GM what year was it? Maybe starting back in the G8 and early days of Gen5s it was the case?

Totally agree on the purposes of the OEM oil cooler! Thanks for the reply.

12 so it would be 10/11/12 model years.