[Z06] Large difference between coolant and oil during warm up phase?
#41
Pro
#42
#43
Team Owner
Originally, I thought about doing the Dewitts and C5Z51 lines...but I have a GMPP and will most likely extend it. So my next thought was the GM ZR1 radiator and oil cooler set up. I believe the Dewitts route is cheaper than the ZR1 stuff...but I imagine my GMPP would remain in tact in the event of some sort of catastrophic failue as long as I have genuine GM parts that were available on the Z06 a few years after mine. I thought the T-stat would be the easiest way to go, but it sounds like its more work and money than I anticipated.
#44
Team Owner
Don't need z51 lines, but it does clean up the install a little.
#46
Team Owner
You can tweak/bend the factory z06 lines enough to work, but IMO the $130-140 for the z51 lines is worth it. I did both.
If you have no issue with the car taking awhile to warm up and can drive easy enough, then you don't have to do anything but monitor oil temps and make sure not to beat on it <160 or so. Sounds like that is what Mark does and works for him, others would like it to come up quicker.
If you have no issue with the car taking awhile to warm up and can drive easy enough, then you don't have to do anything but monitor oil temps and make sure not to beat on it <160 or so. Sounds like that is what Mark does and works for him, others would like it to come up quicker.
#48
Melting Slicks
Z51 Lines
I agree with Unreal above the Z51 lines are better to put in if going Dewitts they have less bends in them and are very easy to install. Furthermore, you can sell your Z06 lines to recoup the difference. The Z06 lines are just way to long for the Dewitts it can work but a hassle.
#49
Team Owner
Wouldn't call it inexpensive. The part it self is $200, but the lines/adapters/etc are not cheap either to put it in.
#50
Pro
I bought a 12x18 sheet of 26 Ga sheet metal and cut it down to fit over the Z06 cooler. The top was bent around a 3/4' dowel to imitate the curve of the cooler. I also cut two notches on the top and bottom for the zipties, which ensures it will stay in place. No empirical data yet with this setup, but my first attempt with a rubber stair protector gave me about 20 F higher oil tmps. This sheet metal one covers about 1.5" more of the cooler (leaves about the size of the external stock Z51 oil cooler). It's been primed and painted low gloss black (High temp rustoleum) to keep it discreet. Cost me about $10 for the sheet metal and primer and only took about 30 min to cut with tin snips and bend up by hand.
Yesterday I decided to cover the stock oil cooler. I used a piece of sheet aluminum from Lowes. I had to cut it to exactly 6" tall by 21.5" long. This size will cover the entire cooler. The oil still passes through the cooler and the sump tank so I don't think there is a risk of oil temps getting too high. To hold the sheet on I used two zip ties. I used the ones in the HVAC section used to hold flex pipe on in your duct system. These ties are the perfect width to fit between the ridges on the oil cooler.
Today it was 32 degrees outside. After 20 minutes of normal driving I was able to hit 192 degrees oil temp driving in the city. I am extremely happy as I spent about $20 and a half hour of time. I was planning on doing the ZR1 conversion so I saved myself about $1000. I do not track my car so I am going to leave it on and test it in the summer. Since there is still airflow behind the cooler I am predicting it will still keep the temps below 230 or so.
Today it was 32 degrees outside. After 20 minutes of normal driving I was able to hit 192 degrees oil temp driving in the city. I am extremely happy as I spent about $20 and a half hour of time. I was planning on doing the ZR1 conversion so I saved myself about $1000. I do not track my car so I am going to leave it on and test it in the summer. Since there is still airflow behind the cooler I am predicting it will still keep the temps below 230 or so.
After my first drive I got the Z06 out a few days later when ambient temps were up maybe 5 degrees or so from the first drive. That time I noticed that oil temps got just above 220 and that coolant temps were 215-220, which is well above normal for ambient temps at 60-65. Driving was not aggressive.
I decided to remove 1 of the 2 "blankets", leaving the cooler 50% covered, and then took it out a couple of days later with ambient temp at just above 60. Coolant temps were back to normal. Oil warming was still pretty comparable, perhaps a bit slower. Temps settled in between 185-190 and stayed there on the same uphill, curvy section I described on the first drive. Again, driving was not aggressive for the sake of consistency. I think I'll stick with this set up unless colder temps force me to cover more of the cooler. I'll just add 1-2" of coverage at a time, as needed.
I decided to remove 1 of the 2 "blankets", leaving the cooler 50% covered, and then took it out a couple of days later with ambient temp at just above 60. Coolant temps were back to normal. Oil warming was still pretty comparable, perhaps a bit slower. Temps settled in between 185-190 and stayed there on the same uphill, curvy section I described on the first drive. Again, driving was not aggressive for the sake of consistency. I think I'll stick with this set up unless colder temps force me to cover more of the cooler. I'll just add 1-2" of coverage at a time, as needed.
Next I will add an oil pre-heater:
DIY: Oil Preheater Install
How to Pre-Heat Your Oil for 60(ish) Dollars!
Last edited by bjmsam; 01-18-2015 at 01:42 PM.
#51
Pro
The following graph compares oil temperature and coolant temperature after a cold start in winter as logged by the Torque app running on my Android head unit monitoring my OBDLink MX. The oil temperature values deviate from those displayed on the dash after 100°F (30° = 30° and 100° = 100°, but 124° = 158°, so the default A-40 PID calibration clearly needs some work), but you get the idea. I typically drive gently until the oil temperature is at least 100°, which on this run took almost 10 minutes (and it took almost 25 minutes for the oil temperature to level out where I ended the graph)! What are the latest opinions on oil cooler thermostats such as those from Improved Racing and Mocal for those of us with the stock oil cooler?
The ambient temperature was roughly the same both times. Here are some observations that might support a hypothesis that the ECU is manipulating oil temperature sensor values when reporting them via OBD and displaying them via the DIC (the aforementioned discrepancy).
1. The initial coolant temperature value was slightly lower than it was last time, but the initial oil temperature value was slightly higher than it was last time. Then and now, the car had been sitting for days, so I would expect both fluids to have identical initial temperatures each time. This is puzzling; perhaps the ECU considers intake air temperature a factor when adjusting the oil temperature sensor values? Note that coolant temperatures reported via OBD and displayed via the DIC are identical at all times.
2. With the EGM-113 installed, it took less time for the oil to reach a higher temperature as expected. When the DIC leveled off at 183-5°F, the OBD reported 157-162°F (both reflect a significant improvement over stock). Upon returning home with the oil at that temperature, I shut off the engine and immediately aimed an IR thermometer down into the dry sump dip stick hole with a reading of 195°F. I should have thought to do that last time!
Regardless, I am very pleased with the results and believe this is how the Z06 should have been configured from the factory (better than ZR1 approach IMO).