Time to solve my ZL1's over heating issue on the track

[BaylorCamaro]

Looking for some advise from the track guru's (I'm looking at you X25).

*Warning a bit of a long read*


Seems like after a year of tracking and doing slight mods here and there I've finally needing to address engine cooling and radiator cooling.

A little background first, I track (road course) my 2013 Camaro ZL1 4-5 times a year. it is lightly modded: full exhaust, intake, injectors, tune, some suspension and cooling things (heat exchanger and reservoir for the blower), making just shy of 600 rwhp. I've been doing HPDE events for about a year now and have logged about 500-600 track miles. I started off with the factory oil, Mobil 1 5w-30 and made the switch fairly early on to Pennzoil Platinum under the suggestion of one of the engine builders I know. Unfortunately I didn't have access to 5w-30 or the Ultra Platinum (only Platinum) so I've been using 10w-30. I live in Houston Texas and combine that with a forced induction engine doing 20-30 minute track sessions, the heat that is generated is something that would make the devil himself sweat. From reading X25's post I've come to find the factory oil temp gauge isn't accurate past 266 F. Oil analysis shows the viscosity is still good and no signs of sheering/degrading.

Overheating Two Track Events Ago:
Two track events ago Alec Udell, pro driver of the #17 GMG Porsche GT3 Cup car in the Pirelli World Challenge did a 20-30 minute stint in my car with me ridding shotgun and unfortunately we got an engine overheat warning, the radiator coolant temp was pretty close to being maxed out on the analog gauge (can't remember what temp that is) so we did a cool down lap and brought it in to sit and cool. Later that day I was really pushing the car chasing my buddy in his Z/28 and it started to overheat again, so with that being the second time in the day (and first track event ever to overheat) I decided to call it a day. Last week I changed the radiator fluid and supercharger intercooler fluid to Engine Ice along with changing the thermostat and it seems to have brought daily driving temps down 20-25 degrees. How that will translate to the track, I'm not sure yet but I suspect that will only delay overheating and not really solve the problem.

My Historical Oil Analysis:
My most recent oil analysis (see below) shows increased aluminum and iron contents, possibly suggesting piston scuffing from what I would assume to be result of either oil thinning or slight starvation (no dry sump on this car). This past oil analysis was conducted last week, I have since changed to Pennzoil Ultra Platinum 5w-30. However I may go to a 0w-40.

The main reason I haven't gone to a really heavy oil such as a 15w-50 is due to the fact that this isn't a dedicated track car. While it isn't my daily either, I still drive it on the weekends and to various car meets. I've had the car for three years (almost to the day) and I'm just about to tick 17k miles.

The oil analysis below has three different samples/logs. Each with increasing mileage and number of track events. The first sample was done with only 1,000 miles on the sample and 1 track event this was Mobil 1 5w-30 and obviously it came back completely fine. The second sample was with 2,730 miles on the oil and two track events plus one autocross event. Oil still appeared to be OK. Third (most recent) sample is with 5,029 miles on the oil, 4 track events plus two autocross events. Both the second and third sample were with Pennzoil Platinum 10w-30.



The Solution:
Now I realize that the oil weight isn't the primary issue here. The lack of cooling capacity is what I need to address. From all of the research I've been doing and the great information that has been posted by both Orange Crush 1LE and X25 I will be installing an aftermarket oil cooler. Orange Crush 1LE (and maybe X25) no longer use the radiator coolant to "cool" the engine oil. I think by doing this the benefit of the radiator coolant not having to do double duty is the real benefit.

I will need to do some research on the oil cooler selection, unlike both Orange Crush 1LE and X25, I've got a ZL1 and I need to look at fitment and where I'm going to be mounting things. I think the mounting location of Orange Crush 1LE (to the side of the radiator and in my case intercooler) will be the preferred location as opposed to X25's centralized location in front of the radiator. However this is getting into uncharted territory for me as to what I'm going to need and if I'm over looking something for this build.

I haven't really found a good thread for a ZL1 address cooling for a road course application, people are too busy drag racing them I suppose. Had I known I was going to get so involved with HPDE events I would have just bought a 1LE or Z/28

[White_SS/RS]

Yeah, sounds like you need the dedicated oil cooler, perhaps as well as adding a more efficient radiator. Sounds like your on the right track with the engine ice and low temp thermostat. I would also suggest reducing the amount of antifreeze in your coolant. Not sure what your potential for freezing is in TX, but straight water with engine ice or water wetter is much better.

As far as your oil analysis, I think running a 0/40 would be a good move. The extra aluminum and iron were probably from the overheating episodes and if you can mitigate the heat with better cooling you probably won't have the metals in the oil like that.

One note on the temp gauge... Don't use the DIC, if you have the gauge cluster, it reads correctly and will also read over the infamous 266*.

[JDP Motorsports]

It sounds like it's time for a radiator and an external oil cooler. I run the C6 Z06 oil cooler set up on my car and it works great for the oil. I'd go with a Ron Davis radiator with the internal oil cooler like we run in the car below. We have proven solutions.

2014 OUSCI Chase Car driven by Bimmer World driver James Clay during back to back to back 20 minute sessions making 725 WHP and 700 WTQ..


What is your AFR? I would look at the JGR Driven LS30 or possibly the JGR DT40 which is a 5w40 as it has a great additive package including zinc.

Kind regards,

Jordan Priestley
888.308.6007

[BaylorCamaro]

Originally Posted by White_SS/RS

One note on the temp gauge... Don't use the DIC, if you have the gauge cluster, it reads correctly and will also read over the infamous 266*.

I never use the DIC for oil temp but I've looked at it for coolant temp. Is it not accurate for the coolant too? Also, the oil temp on the gauge cluster is in fact accurate? I was under the impression that it was calculated like the DIC?? My gauge cluster shows oil in the 290ish range after a track session.

Originally Posted by JDP Motorsports

It sounds like it's time for a radiator and an external oil cooler. I run the C6 Z06 oil cooler set up on my car and it works great for the oil. I'd go with a Ron Davis radiator with the internal oil cooler like we run in the car below. We have proven solutions.

I like Ron Davis products, I run their heat extractor for my blower. The radiator is a bit pricey though. Ron Davis makes a radiator with an internal oil cooler? So it's still utilizing engine coolant to cool the oil? It seems to me, and correct me if I'm wrong that a stand alone oil cooler will free up a lot of the cooling capacity from the radiator (not to mention an oil cooler cost less than a performance radiator).

Originally Posted by JDP Motorsports

What is your AFR? I would look at the JGR Driven LS30 or possibly the JGR DT40 which is a 5w40 as it has a great additive package including zinc.

Not sure off the top of my head, I'd have to look. However Matt from FSP tuned the car, he knows I abuse the car on the road course so he kept that in mind. I believe it is fairly conservative as far as ZL1 tunes go.

[LagunaSecaZL1]

BaylorCamaro,

I track my 2013 ZL1 at Laguna Seca and Thunderhill. Laguna Seca is 10 miles from the Pacific so that track is relatively cool. Thunderhill is in the central valley and is hot(over 95-100*). I have upgrade to the Ron Davis Heat exchanger and Ron Davis Radiator. http://www.camaro5.com/forums/showpo...9&postcount=11
http://www.camaro5.com/forums/showpo...1&postcount=17

I hav also added a Lingenfelter 172* thermostat. I thought the 160* might be too cool. The engine temps were a little cooler around town with the RD Radiator. With 172* thermostat the car runs at 185-189 on the highway(80-90* ambient) and gets to 210 when driving on backroads. Recently I got the oil temp to 240 when driving in 2nd gear and playing with the throttle, but the coolant was still under 220*.

I will say that ambient air temperature is a big factor with the ZL1 and its not linear. If the temp is 95* then it will cause the water/oil temp to rise much faster than 85* and much faster than 75*(rate of change, not just increased temps). In retrospect I would probably go with an AFCO heat exchanger, because it comes with integral fans. Since I didn't buy that, keep on reading.

If you turn on your A/C, the radiator fan will run immediately(I don't know if it is full speed), I have tried this at stoplights and my car will be at 210* (no A/C)and then drop all the way to 190* when it is 80* ambient while stationary. While this sounds counterintuitive, the radiator fans cool more than the A/C compressor load heats. Without buying new parts, try running with the A/C on. I would like to buy a manual add on pusher cooling fans. This mod would be a little bit of a pain to install since you have to remove the bumper. But it would would probably be very helpful and easy to use.

To sum up, my recommendations in order of price and helpfulness-
1- Run track day in spring or fall, not convenient.
2- Run A/C - if it doesn't help, turn it off, no cost.
3- 160*, 172* Thermostat, cheap, little to no downside, easy to install.
4- Ron Davis radiator, can not use with DP3 Reservoir because the radiator is too thick, $1200. Works better with lower thermostat.
5- Extra cooling pusher fans or AFCO heat exchanger with pusher fans.
6- Remove stock oil coolers and reconfigure with Race cooler with thermostat, Expensive and involved installation. Don't screw up. I have read X25 and Orangecrush posts

I just sent in my oil to Blackstone and I will be posting the results when I get them. I have been using 5w-30 and we can compare. I did 6500 miles and two track days. It was the second oil change, and I have owned the car since new.

[JDP Motorsports]

Originally Posted by BaylorCamaro

I never use the DIC for oil temp but I've looked at it for coolant temp. Is it not accurate for the coolant too? Also, the oil temp on the gauge cluster is in fact accurate? I was under the impression that it was calculated like the DIC?? My gauge cluster shows oil in the 290ish range after a track session.


I like Ron Davis products, I run their heat extractor for my blower. The radiator is a bit pricey though. Ron Davis makes a radiator with an internal oil cooler? So it's still utilizing engine coolant to cool the oil? It seems to me, and correct me if I'm wrong that a stand alone oil cooler will free up a lot of the cooling capacity from the radiator (not to mention an oil cooler cost less than a performance radiator).



Not sure off the top of my head, I'd have to look. However Matt from FSP tuned the car, he knows I abuse the car on the road course so he kept that in mind. I believe it is fairly conservative as far as ZL1 tunes go.

The factory oil temp is calculated but I don't like to see that number go much past 290*. I see 290-300 on my gauge which is around 240-245 actual...

It sounded like the main problem was coolant temp? Why address the oil temp issue and not the coolant temp issue? We run the Ron Davis radiators in the Vette's we build with their oil to water coolers and the work very well. You have to remember you're doubling the cooling capacity with a much more efficient set-up. We also have air to oil cooler options but the RD works very well and has been proven.

I know Matt is awesome. I was just curious where the AFR was as running it a little richer can help to keep the cylinders slightly cooler.

Originally Posted by LagunaSecaZL1

BaylorCamaro,

I track my 2013 ZL1 at Laguna Seca and Thunderhill. Laguna Seca is 10 miles from the Pacific so that track is relatively cool. Thunderhill is in the central valley and is hot(over 95-100*). I have upgrade to the Ron Davis Heat exchanger and Ron Davis Radiator. http://www.camaro5.com/forums/showpo...9&postcount=11
http://www.camaro5.com/forums/showpo...1&postcount=17

I hav also added a Lingenfelter 172* thermostat. I thought the 160* might be too cool. The engine temps were a little cooler around town with the RD Radiator. With 172* thermostat the car runs at 185-189 on the highway(80-90* ambient) and gets to 210 when driving on backroads. Recently I got the oil temp to 240 when driving in 2nd gear and playing with the throttle, but the coolant was still under 220*.

I will say that ambient air temperature is a big factor with the ZL1 and its not linear. If the temp is 95* then it will cause the water/oil temp to rise much faster than 85* and much faster than 75*(rate of change, not just increased temps). In retrospect I would probably go with an AFCO heat exchanger, because it comes with integral fans. Since I didn't buy that, keep on reading.

If you turn on your A/C, the radiator fan will run immediately(I don't know if it is full speed), I have tried this at stoplights and my car will be at 210* (no A/C)and then drop all the way to 190* when it is 80* ambient while stationary. While this sounds counterintuitive, the radiator fans cool more than the A/C compressor load heats. Without buying new parts, try running with the A/C on. I would like to buy a manual add on pusher cooling fans. This mod would be a little bit of a pain to install since you have to remove the bumper. But it would would probably be very helpful and easy to use.

To sum up, my recommendations in order of price and helpfulness-
1- Run track day in spring or fall, not convenient.
2- Run A/C - if it doesn't help, turn it off, no cost.
3- 160*, 172* Thermostat, cheap, little to no downside, easy to install.
4- Ron Davis radiator, can not use with DP3 Reservoir because the radiator is too thick, $1200. Works better with lower thermostat.
5- Extra cooling pusher fans or AFCO heat exchanger with pusher fans.
6- Remove stock oil coolers and reconfigure with Race cooler with thermostat, Expensive and involved installation. Don't screw up. I have read X25 and Orangecrush posts

I just sent in my oil to Blackstone and I will be posting the results when I get them. I have been using 5w-30 and we can compare. I did 6500 miles and two track days. It was the second oil change, and I have owned the car since new.

The AFCO heat exchanger with fans is great for drag racing but not so much for road course... It is too big and blocks flow to the radiator and the fans do absolutely nothing once you're moving; in fact the block flow..

You also do not want to run your A/C.... You can simply tune the fan control to turn the fans on early...

Kind regards,

Jordan Priestley
888.308.6007

[sting808]

I don't track but I autoX and encounter heavy traffic in +90* ambient. Using DeWitt(same as BeCool) with the built-in manual transmission cooler in the lower radiator. 160 stat and KB HE on the bottom front inlet. On pavement when ambient is 93-97*, AC on, my coolant temp is 183 in traffic and engine oil is slightly under 200 hash mark. Coolant temp varies with AC, front air flow, and RPM. At cruising in 6th at 1100-1200 RPM at ~60mph, coolant temp can reach 192 when AC cycles off. But, can go as low as low 170s in cooler evening temps. When fans come on, temp drops. Fan is tuned the come on at 192 and 100% little over 200* if I remember tune. (W/O AC). If I increase rpm to 1800-2000, coolant temp drops since water pump pushes more volume. This is going to be another issue during normal driving, but racing RPMs should be pushing more coolant volume though the thicker radiators.

I've played around with about 4 different stats between 160, 180, 186(OE and 3rd party). I've found stat design appears to affect coolant flow dramatically based on observed temps. I've made sure that I've purged air from system tried driving in different conditions. SLP 160 and GM OE works the best, while others idle over 200 and requires higher RPM for more coolant flow to bring down temps. I haven't tried the balanced designs or lingenfelters 172, but I'm happy with the OE for cooler weather and SLP for summer time. I've since left the SLP 160 in for the last year.

This is my unscientific observations on stats with a 2" core design radiator. I considered the Afco HE with fans, but wonder if it would impact radiator airflow and may need to run the Afco fans 100% since it mounts on the upper portion of ruts front clip. Was thinking of a temp sensor fan control for the Afco since they are louder. If you're 100% purpose built for track, go for it... Not sure how the hood vents and aero panels under the front will affect results since I have a 2010 SS. I believe the DeWitt go for ~$600-700. I paid a lot more in 2011.

[sting808]

Originally Posted by JDP Motorsports

The AFCO heat exchanger with fans is great for drag racing but not so much for road course... It is too big and blocks flow to the radiator and the fans do absolutely nothing once you're moving; in fact the block flow..

You also do not want to run your A/C.... You can simply tune the fan control to turn the fans on early...

Kind regards,

Jordan Priestley
888.308.6007

Thanks for the clarification on the AFCO for airflow. Without a custom OS, I thought 192 was the earliest you can program the fans to turn on. Could go 100% at 192 or slightly higher, but wonder how long the fans will last.

BTW, this is Lionel. Can't wait to install the new calipers this weekend.
Installing softer Draco 350 lbs/ft springs up front same time.

[wakespeak]

Seriously go with an ACEA rated A3 oil. The high temp high shear rating HTHS is the difference.. A value of 3.5 or higher is what you need. American gf5 xw30 oils are only in the 3.0 range. They are thin for fuel economy.

I use Pennzoil Euro L found on Amazon in 5w-30. Mobil 1 10w30 high mileage and 0w-40 also work.

This will help protect your bearings (a lot of cars use aluminum instead of lead babbit now) even if you are successful with the oil cooler.

[backeddy]

Ahhh yes the dreaded ZL1 heat soak issue, even though Laguna is cool usually, this problem always rears it's ugly head.....I get done running an hour straight and head for lunch, ZL1 owners head for damage control on their engines. This biggest problem in my eyes is that the perfect spot for coolers is occupied by brake ducts. As pete and probably OC will tell you, this is an issue. Do you ne3ed brakes or a cooler motor?? Anyone experiment running with the ac on to keep the fans moving?

[White_SS/RS]

Originally Posted by JDP Motorsports

It sounds like it's time for a radiator and an external oil cooler. I run the C6 Z06 oil cooler set up on my car and it works great for the oil. I'd go with a Ron Davis radiator with the internal oil cooler like we run in the car below. We have proven solutions.

Jordan Priestley
888.308.6007

Will the C6 Z06 kit fit the SS?

Originally Posted by BaylorCamaro

I never use the DIC for oil temp but I've looked at it for coolant temp. Is it not accurate for the coolant too? Also, the oil temp on the gauge cluster is in fact accurate? I was under the impression that it was calculated like the DIC?? My gauge cluster shows oil in the 290ish range after a track session.

It's not that the DIC is inaccurate, it just doesn't display past 266 but the analog gauge will. I don't believe there is an issue with the water temp in the DIC.

[Todd in Vancouver]

I'm currently in a hotel waiting to do a track day tomorrow at The Ridge in Washington and the temps right now in the West are pretty damn hot. My car is all stock except for a CAI and I put a bottle of water wetter in my cooling system so I Will be watching my temps closely tomorrow during my track time.

I've had some hot temps while on the track but nothing alarming so far but I only drive at 7/10ths so maybe thats why. I will be adding some extra oil cooling soon as it is a concern and that is the only issue that has popped up is oil temps getting uncomfortably hot for my taste. I also only use Pennzoil Ultra and to date have had no oil issues. Will definitely be following along this thread to see where it goes and fixes that come out of it.

[LagunaSecaZL1]

Jordan,
I hear ya on the blocking flow with AFCO and that's why I bought both the Ron Davis units from you. I am not big on "tunes" because I live in California and when they smog it comes up as a reflash. My car is also under warranty. I recently brought my car in for an oil change and said my brakes are pulsating. The service writer saw the Laguna Seca License frame and tow hook. He asked if I tracked the car and I said yes. He then asked if I use DOT4 and I said yes. He then said, I'll either get you new rotors or have them turned. The dealership ended up turning the rotors for free, and I have tracked it since and they are fine. This is why I don't want to get a tune, because it should be easier to keep my warranty intact.

Sting808
You are on the right track testing and trying a few different $30 Thermostats. It is very beneficial to use a lower temp thermostat, low cost and easy to install and reverse. This page shows that two thermostats with the same rating operate differently-http://reischeperformance.com/tstatinfo.html


If money is no object, buy a; $1200 radiator, $550 Heat Exchanger, $30 Thermostat, Tune, $1000 Oil cooler setup(parts and labor guess) and be done with it. I report back after July 19th at Thunderhill how my 172* thermostat works with my RD Radiator at probably a 95* track day. At Laguna Seca, my temps were fine, but it was only 75* ambient.

[LagunaSecaZL1]

Originally Posted by Todd in Vancouver

I'm currently in a hotel waiting to do a track day tomorrow at The Ridge in Washington and the temps right now in the West are pretty damn hot. My car is all stock except for a CAI and I put a bottle of water wetter in my cooling system so I Will be watching my temps closely tomorrow during my track time.

I've had some hot temps while on the track but nothing alarming so far but I only drive at 7/10ths so maybe thats why. I will be adding some extra oil cooling soon as it is a concern and that is the only issue that has popped up is oil temps getting uncomfortably hot for my taste. I also only use Pennzoil Ultra and to date have had no oil issues. Will definitely be following along this thread to see where it goes and fixes that come out of it.

Todd, I would recommend turning on the A/C on the cool down lap and in the pits. It may not help on the track since the airflow should be good. Again, this is an easy experiment.