I have had my corvette for about 6 months now. 2012 3LT. Only issues I have encountered was a bad injector since I’ve owned her. Now ever since My oil was changed my car seems to be running “hot” in my book. I used mobile 1 filter and oil (5w-30) 5.5 quarts. Car is daily driven and am located in Florida. During normal driving, oil pressure gets as low as 19 during hot idle. Oil temp on the high side gets to 230 degrees on hot idle. Coolant temp is at 220-225 and trans temps 210-215 all at hot idle. Coolant temp drops to 190 and trans temp 170 during highway cruise. It seems that once my oil begins rising, it is having an issue cooling off. Does anyone have any advice? Are these normal operating a temps? Any advice would be appreciated! It also seems that the car could be pulling timing as I seem to loose power and begin to hear a ticking under the car. Only modifications are long tube headers, no cats to a flow master axle back.

 

Just curious how many miles are on it?

 

just under 93k

 

Those idle temps are what you would expect, since there is no airflow other than what the fan and its programming provide. The hotter the oil, the lower the pressure is going to be because the viscosity of the oil drops. At 230F oil temps, I'm not surprised at that pressure. Once the oil in the sump has heated up, there is nothing to cool it down directly, since the A6's didn't come equipped with external engine oil coolers, so the oil will cool gradually as the block temperature comes back down. The tranny temperature is not surprising either, since the tranny fluid cooler is in the rad, and when you're running at 225, you're not cooling the tranny fluid, you're heating it up. The fan programming will give you some idea of why things run as hot as they do. The fan doesn't kick into high until you reach 225.

 

that was extremely informative, thank you! Is there anything you would recommend I keep my eye on?

 

The wet sump engines are supposed to take 6 quarts of oil according to the manual. You added 5.5 quarts. I'd just check that on a warmed up engine, the oil level on the dipstick is at the top of the hatched area. Your highway temps seem fine, so the rad is probably not obstructed by debris (yet). Oil pressure at highway speeds should be near the 40psi mark. What are you seeing at highway speeds?

 

cruising speeds anywhere from 29-45 and when wot to redline 55-65. Coolant 190 steady and trans 175-195

 

Take the fuel rail covers off and that will get you five degrees cooler at red light in traffic....free.

 

How do we program the fan to go to high speed at lower temps

 

Don't do it. Reportedly, the connector for the fan is not up to it, and will melt if you increase the duty cycle of the fan. If you decide to do a hardwire bypass of the connector, then you risk melting the fan controller. This is if you keep the stock rad. If you replace the rad with a DeWitts all aluminum rad, the cooling capacity increases by 50%, so the fan has less work to do, and you should be able to modify the fan table to bring the fan on sooner and not risk the connector. I think you can use HPTuners to modify the fan table, but I'm not sure. I've got a DeWitts rad, but that doesn't stop the coolant from reaching 221 -223 if I'm stuck in traffic, but I do notice that the fan doesn't run as much in those cases compared to when the stock rad was there.

 

Which connector melts? Can't we just replace the connector?

 

The connector that melts is the 3 pin one that electrically powers the fan. 2 wires for power, 1 for control.
Read this thread: https://www.corvetteforum.com/forums...connector.html
Then read this thread: https://www.corvetteforum.com/forums...as-struck.html
There's lots of threads like this if you search for them, so you get the idea of the fact that the connector does melt, and what you might do about it. I'm of the opinion that it's not worth risking melting the controller, which is the next thing to go if you reinforce or bypass the connector. Bigger rad is a better option, but of course much more expensive.
Here's where the connector located. Clips onto the fan bracket assembly.

 

Don't know if it's possible to program the radiator cooling fan to run at 100% duty cycle but GM advises the fan should never be run at greater than 90%. Running the fan at above 90% has been shown to overheat the connector from the fan controller to the fan. I had my tuner guy set mine at 88%. Mine is a '08 Z51, M6, with BTR Stage 2 cam/kit. The engine never gets above 217 deg. F. in heavy traffic, and often will drop to the 180's on the open road.

 

Here in SE PA, we get in July and August very humid air, very sticky. But I have a 07 and even real hot, in-traffic and stop and go situations my engine temps wander up around 208 - 212 degrees, but once out and moving they come down 6 to 10 degrees. In the cool weather like now, they go to 205 and pretty much stay there. Were I you, I'd install an oil cooler. Chevy stopped installing oil coolers in 1992 when they started using Mobil-1 5W/30 as standard oil fill from the factory, but that doesn't mean that using a oil cooler is a bad idea. Many guys here who track their cars routinely install oil coolers for this very reason. And despite some folks ideas, Modern Synthetic motor oil should be operated at around 200 + degrees in an engine, the additives packages don't even get into use under 200 degrees. Detergents, friction modifiers rubber lubricants' and the oil itself runs better once above 195 degrees. Here a brief outline by Motor Trend author,

*** "For a dual-purpose car, engine oil needs to be at least 220 degrees F to burn off all the deposits and accumulated water vapor. For every pound of fuel burned in an engine, the combustion process also generates a pound of water! If engine sump temperatures rarely exceed 212 degrees (water's boiling point), the water will mix with sulfur (another combustion by-product) and create acids that can eventually damage bearings.

As for ultimate power potential, the general consensus among most racers is that hot oil and cool water make more power in most engines. Cold engine oil causes excessive frictional drag on the bearings and cylinder walls. A quality conventional motor oil will tolerate oil sump temperatures of up to 250 degrees, but starts breaking down over 275 degrees. The traditional approach is to try to hold oil temperatures between 230 and 260 degrees. Even on a short-duration, drag-only combo where oil is frequently changed, I would not want to routinely see under-200-degree oil temps.

A full-synthetic oil will withstand sump temperatures in excess of 300 degrees, and for hard-core professional racing, some oval-track race teams are experimenting with ultra-thin, specially formulated, race-only synthetics operating at 350 degrees or even higher.

Also remember that a high-end engine is built as a total combination. Piston-to-wall clearances, piston ring end-gaps, and bearing clearances are specifically tailored to match the engine oil's characteristics and intended operating temperature."

But If I were you and your considering a long engine life, I'd go ahead in install a good quality oil cooler.

 

Z51 and GS m6s came with external engine oil coolers. Z06 and ZR1 as well. I had a Z51 cooler installed on my A6. Bolted right up with the correct shroud. So they didn't stop in 1992.

 

Might be helpful if we know how to go about installing a external oil cooler. How did you find and install yours ?

 

Off the shelf GM parts https://www.gmpartsdirect.com/v-2011...em--oil-cooler
Parts 1 2 3 and 4 near the bottom, plus a different shroud and a few nuts and bolts. You could probably modify the existing shroud the difference being there's a slot cut in the correct shroud for the lines to pass. A shop did the install and I believe the front fascia had to come off. 20 years ago I wouldn't have hesitatated to have done this myself. Crawling around under cars is no longer the fun it used to be. Driving still is.

 

Just for some added information on engine temps. Living in the Valley of the Sun (Metro Phoenix) we will have summertime temps of 105 to 115 in the dog days of summer, usually July and August. I have a 2007 C-6 with an A & A S/C and air to air intercooler. In traffic the engine temp, with the A/C running, will increase to 230-235, then on the freeway will "cool down" to 220-225. IF.....I have to sit in traffic, I will have to turn off the A/C until I get moving again, and the engine temp will stay at about 225. Again, once I get moving I can turn the A/C back on and the same routine will have to take place to keep the engine temp in check in stop and go traffic. Now that we are only in the 70's, no problem what-so-ever as the engine temp will stay around 215. I am thinking with the limited room due to intercooler, I can still install a 6" "pusher" fan on the area to to left of the intake tube. Right now it's not necessary, so I will probably wait until March when the "warmer temps" 80-90 will return and I will install it at that point and see if it makes any difference at all. Hope this helps......