View Poll Results: If you've Overheated What is Your Stage Aero 1, 2 or 3
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ZO6 overheating issues ***MEGA Merge***
#2062
I have now read "countless" threads with opinion and hypothesis.
Respectfully, no opinion, hypothesis, complaint .
HAS ANYONE SOLVED THE HEAT PROBLEM
If so please share it with us and the data to support your claim.
This may be a one post thread, and I really don't mind.
Best
Respectfully, no opinion, hypothesis, complaint .
HAS ANYONE SOLVED THE HEAT PROBLEM
If so please share it with us and the data to support your claim.
This may be a one post thread, and I really don't mind.
Best
#2063
Tech Contributor
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Location: Charlotte, NC (formerly Endicott, NY)
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#2064
Race Director
Didn't someone post in another thread that he had a larger radiator and thought that might fix it? I thought he said that he was going to have to make a small mod to allow figment.
#2065
Race Director
Member Since: Aug 1999
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Since I have a 16 on order........ I'll ask this question. I was told by a tuner that the Hallteck(?) induction reduces the heating issue and adds some significant HP.
Is this not the case?
He says it allows more airflow and allows the engine to run cooler. Also indicated the restricted stock system was designed to meet CA air pollution requirements and GM knew a simple improvement, note I did not say fix is a bigger breather.
As a soon to be Z owner..... I've read lot of threads and concluded you have 2 turbo chargers turning 10K RPM and you are going generate heat. I've also concluded that the 3 to 5 track days I do a year that any overheating or track heatsoak can be managed by balancing track time.
I don't expect nor from what I am hearing would my gas tank allow me to cruise around the track in a 24 hour event.
I am not expecting a heat issue, over or soak driving everyday on the roads. Might be a track only issue????
Can someone verify a novice's expectations?
Thanks!
Is this not the case?
He says it allows more airflow and allows the engine to run cooler. Also indicated the restricted stock system was designed to meet CA air pollution requirements and GM knew a simple improvement, note I did not say fix is a bigger breather.
As a soon to be Z owner..... I've read lot of threads and concluded you have 2 turbo chargers turning 10K RPM and you are going generate heat. I've also concluded that the 3 to 5 track days I do a year that any overheating or track heatsoak can be managed by balancing track time.
I don't expect nor from what I am hearing would my gas tank allow me to cruise around the track in a 24 hour event.
I am not expecting a heat issue, over or soak driving everyday on the roads. Might be a track only issue????
Can someone verify a novice's expectations?
Thanks!
#2066
Thats the thing. When there is a company like LG motorsports ect that do come out with a rad and oil cooler kit that does lower temps to what these cars should be on track then Im sure it will be big news. But Im sure until then everyday someone else will as the SAME mundane question as been asked 6 months in a row now.
#2067
I don't own a new Z but reading all of this and my experience in keeping race engines cool (8-8.2k rpm BMW Race Motors) I have feeling the fix will be relatively "simple". In these high rpm, high compression, bmw motors the main focus in the cooling is:
1. good radiator cooling capacity, that's a given.
2. Oil cooling capacity - on these motors we run an independent BIG oil cooler. Running even 90min races (7-8+k rpm) we see 200 max oil temp post oil cooler and 260-270 max oil temp in the sump after the oil has circulated through the engine. The is PERFECT temps for modern race oils.
The key is independent Oil cooler from the Water Cooling of the engine. It's my guess that combining a boosted engine and the heat that creates, then you use an oil cooler that is relying on water temp to cool it. It's not rocket science to think the oil temps post cooler can never be cooler than the water temp and vice versa.. and once that oil goes up on the 260+ range you can't cool it with 200 degree water..
Perhaps we have some engineers in here that can calculate the thermo efficiency of trying to cool 260+ oil with 200 degree water exchanger vs 260+ oil going through traditional cooler with air temp flowing through it between 60-100 degrees. My guess is even a reasonable sized traditional cooler with ambient air as the cooling source will be much more efficient and capable to lower the oil temps.
Plus I believe it is a self feeding loop of heat in the current set up.. water is not cooling the oil and the oil is actually heating the water.. a circular type of thing
Decoupling this oil and water cooling loop, I believe will get you very close if not all the way there to fixing this issue.
1. good radiator cooling capacity, that's a given.
2. Oil cooling capacity - on these motors we run an independent BIG oil cooler. Running even 90min races (7-8+k rpm) we see 200 max oil temp post oil cooler and 260-270 max oil temp in the sump after the oil has circulated through the engine. The is PERFECT temps for modern race oils.
The key is independent Oil cooler from the Water Cooling of the engine. It's my guess that combining a boosted engine and the heat that creates, then you use an oil cooler that is relying on water temp to cool it. It's not rocket science to think the oil temps post cooler can never be cooler than the water temp and vice versa.. and once that oil goes up on the 260+ range you can't cool it with 200 degree water..
Perhaps we have some engineers in here that can calculate the thermo efficiency of trying to cool 260+ oil with 200 degree water exchanger vs 260+ oil going through traditional cooler with air temp flowing through it between 60-100 degrees. My guess is even a reasonable sized traditional cooler with ambient air as the cooling source will be much more efficient and capable to lower the oil temps.
Plus I believe it is a self feeding loop of heat in the current set up.. water is not cooling the oil and the oil is actually heating the water.. a circular type of thing
Decoupling this oil and water cooling loop, I believe will get you very close if not all the way there to fixing this issue.
Last edited by Ruby6spd; 05-07-2015 at 10:53 AM.
#2068
Ncrowe did not try this on a track, he did not say he tried on a track, the information he posted was clearly from driving on the street. I did test on the track and it did not work! or at least not enough testing has be done, This is how people misinterpret information.
The A8 has a supplementary trans fluid cooler mounted in the bottom of the radiator inlet area. I wonder if an M7 could add that cooler and use it for engine oil?
#2069
I don't own a new Z but reading all of this and my experience in keeping race engines cool (8-8.2k rpm BMW Race Motors) I have feeling the fix will be relatively "simple". In these high rpm, high compression, bmw motors the main focus in the cooling is:
1. good radiator cooling capacity, that's a given.
2. Oil cooling capacity - on these motors we run an independent BIG oil cooler. Running even 90min races (7-8+k rpm) we see 200 max oil temp post oil cooler and 260-270 max oil temp in the sump after the oil has circulated through the engine. The is PERFECT temps for modern race oils.
The key is independent Oil cooler from the Water Cooling of the engine. It's my guess that combining a boosted engine and the heat that creates, then you use an oil cooler that is relying on water temp to cool it. It's not rocket science to think the oil temps post cooler can never be cooler than the water temp and vice versa.. and once that oil goes up on the 260+ range you can't cool it with 200 degree water..
Perhaps we have some engineers in here that can calculate the thermo efficiency of trying to cool 260+ oil with 200 degree water exchanger vs 260+ oil going through traditional cooler with air temp flowing through it between 60-100 degrees. My guess is even a reasonable sized traditional cooler with ambient air as the cooling source will be much more efficient and capable to lower the oil temps.
Plus I believe it is a self feeding loop of heat in the current set up.. water is not cooling the oil and the oil is actually heating the water.. a circular type of thing
Decoupling this oil and water cooling loop, I believe will get you very close if not all the way there to fixing this issue.
1. good radiator cooling capacity, that's a given.
2. Oil cooling capacity - on these motors we run an independent BIG oil cooler. Running even 90min races (7-8+k rpm) we see 200 max oil temp post oil cooler and 260-270 max oil temp in the sump after the oil has circulated through the engine. The is PERFECT temps for modern race oils.
The key is independent Oil cooler from the Water Cooling of the engine. It's my guess that combining a boosted engine and the heat that creates, then you use an oil cooler that is relying on water temp to cool it. It's not rocket science to think the oil temps post cooler can never be cooler than the water temp and vice versa.. and once that oil goes up on the 260+ range you can't cool it with 200 degree water..
Perhaps we have some engineers in here that can calculate the thermo efficiency of trying to cool 260+ oil with 200 degree water exchanger vs 260+ oil going through traditional cooler with air temp flowing through it between 60-100 degrees. My guess is even a reasonable sized traditional cooler with ambient air as the cooling source will be much more efficient and capable to lower the oil temps.
Plus I believe it is a self feeding loop of heat in the current set up.. water is not cooling the oil and the oil is actually heating the water.. a circular type of thing
Decoupling this oil and water cooling loop, I believe will get you very close if not all the way there to fixing this issue.
#2070
Drifting
Member Since: Jan 2005
Location: Tucson Arizona
Posts: 1,827
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St. Jude Donor '08
#2071
I was content without you commenting - your need not mine. Best
#2072
#2073
Burning Brakes
My personal opinion is that it is asking too much for a stock, 3500+ lb, 650 hp, air conditioned car to run at race pace for 20+ minutes in 80+ deg ambient and not overheat. I don't know of a single stock car that can do that. Just the airflow restriction from an A/C condenser is a street compromise that significantly reduces cooling capacity.
At a race pace, you will likely see wide open throttle close to 80% of the time on track. And average speeds are probably in the 80 mph range for most tracks. (e.g. I've run 2:25 at CoTA in a street car, so average 84 mph, despite over 160 mph on the longest straight).
Surely someone can do the thermodynamic calculations to see how much surface area and airflow for heat exchangers is required to dissipate the heat from running 650 hp?
For a purely anecdotal comparison, my Radical SR8 track car has a pair of sidepod mounted radiators that are comparable in size to a normal automotive radiator, that are ducted to enjoy what looks like a lot of air flow and no restrictions like an A/C condenser or even a radiator fan and it makes only about 400 hp. It never overheats, running coolant temps consistently under 100 deg C and oil temps under 125 deg C.
I'd bet that it will take pretty radical surgery to get a Z06 to run cool at race pace, as in lots of mods to improve airflow and much different and more numerous heat exchangers.
The solution is non-trivial.
For example, LG appears to be silent right now. I know Lou and he can drive with real pace and I suspect they are having to do a lot of work to try to make a new Z run cool with him driving it to his potential.
This car was not built for a guy who can run serious pace to track for long periods of time - I felt pretty sure of that when I saw the stats of power, supercharging and weight. It is an awesome GT car, very appealing to the drag racers, and great looking. But a track car it is not.
At a race pace, you will likely see wide open throttle close to 80% of the time on track. And average speeds are probably in the 80 mph range for most tracks. (e.g. I've run 2:25 at CoTA in a street car, so average 84 mph, despite over 160 mph on the longest straight).
Surely someone can do the thermodynamic calculations to see how much surface area and airflow for heat exchangers is required to dissipate the heat from running 650 hp?
For a purely anecdotal comparison, my Radical SR8 track car has a pair of sidepod mounted radiators that are comparable in size to a normal automotive radiator, that are ducted to enjoy what looks like a lot of air flow and no restrictions like an A/C condenser or even a radiator fan and it makes only about 400 hp. It never overheats, running coolant temps consistently under 100 deg C and oil temps under 125 deg C.
I'd bet that it will take pretty radical surgery to get a Z06 to run cool at race pace, as in lots of mods to improve airflow and much different and more numerous heat exchangers.
The solution is non-trivial.
For example, LG appears to be silent right now. I know Lou and he can drive with real pace and I suspect they are having to do a lot of work to try to make a new Z run cool with him driving it to his potential.
This car was not built for a guy who can run serious pace to track for long periods of time - I felt pretty sure of that when I saw the stats of power, supercharging and weight. It is an awesome GT car, very appealing to the drag racers, and great looking. But a track car it is not.
#2074
Alcoholics Unanimous
Member Since: Aug 2014
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St. Jude Donor '15-'16
Another day another overheating thread .. and we're barely into May.
Thank god Corvette owners are not particular about their vehicle's performance and are known to suffer quietly.
I sure hope someone at GM/Chevy is paying attention, otherwise by summer's end this one issue is going to destroy the rep of what is an otherwise incredible vehicle.
------------
So far as solving the problem, the best solution theory I have read is to yank the hood when tracking. My suggestion is go from 1st to 7th after 10mph and stay there for the hole session pretending you're momentum racing a spec miata.
Thank god Corvette owners are not particular about their vehicle's performance and are known to suffer quietly.
I sure hope someone at GM/Chevy is paying attention, otherwise by summer's end this one issue is going to destroy the rep of what is an otherwise incredible vehicle.
------------
So far as solving the problem, the best solution theory I have read is to yank the hood when tracking. My suggestion is go from 1st to 7th after 10mph and stay there for the hole session pretending you're momentum racing a spec miata.
Last edited by soulsea; 05-07-2015 at 11:14 AM.
#2075
Drifting
Member Since: Jan 2005
Location: Tucson Arizona
Posts: 1,827
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St. Jude Donor '08
My personal opinion is that it is asking too much for a stock, 3500+ lb, 650 hp, air conditioned car to run at race pace for 20+ minutes in 80+ deg ambient and not overheat. I don't know of a single stock car that can do that. Just the airflow restriction from an A/C condenser is a street compromise that significantly reduces cooling capacity.
At a race pace, you will likely see wide open throttle close to 80% of the time on track. And average speeds are probably in the 80 mph range for most tracks. (e.g. I've run 2:25 at CoTA in a street car, so average 84 mph, despite over 160 mph on the longest straight).
Surely someone can do the thermodynamic calculations to see how much surface area and airflow for heat exchangers is required to dissipate the heat from running 650 hp?
For a purely anecdotal comparison, my Radical SR8 track car has a pair of sidepod mounted radiators that are comparable in size to a normal automotive radiator, that are ducted to enjoy what looks like a lot of air flow and no restrictions like an A/C condenser or even a radiator fan and it makes only about 400 hp. It never overheats, running coolant temps consistently under 100 deg C and oil temps under 125 deg C.
I'd bet that it will take pretty radical surgery to get a Z06 to run cool at race pace, as in lots of mods to improve airflow and much different and more numerous heat exchangers.
The solution is non-trivial.
For example, LG appears to be silent right now. I know Lou and he can drive with real pace and I suspect they are having to do a lot of work to try to make a new Z run cool with him driving it to his potential.
This car was not built for a guy who can run serious pace to track for long periods of time - I felt pretty sure of that when I saw the stats of power, supercharging and weight. It is an awesome GT car, very appealing to the drag racers, and great looking. But a track car it is not.
At a race pace, you will likely see wide open throttle close to 80% of the time on track. And average speeds are probably in the 80 mph range for most tracks. (e.g. I've run 2:25 at CoTA in a street car, so average 84 mph, despite over 160 mph on the longest straight).
Surely someone can do the thermodynamic calculations to see how much surface area and airflow for heat exchangers is required to dissipate the heat from running 650 hp?
For a purely anecdotal comparison, my Radical SR8 track car has a pair of sidepod mounted radiators that are comparable in size to a normal automotive radiator, that are ducted to enjoy what looks like a lot of air flow and no restrictions like an A/C condenser or even a radiator fan and it makes only about 400 hp. It never overheats, running coolant temps consistently under 100 deg C and oil temps under 125 deg C.
I'd bet that it will take pretty radical surgery to get a Z06 to run cool at race pace, as in lots of mods to improve airflow and much different and more numerous heat exchangers.
The solution is non-trivial.
For example, LG appears to be silent right now. I know Lou and he can drive with real pace and I suspect they are having to do a lot of work to try to make a new Z run cool with him driving it to his potential.
This car was not built for a guy who can run serious pace to track for long periods of time - I felt pretty sure of that when I saw the stats of power, supercharging and weight. It is an awesome GT car, very appealing to the drag racers, and great looking. But a track car it is not.
#2076
I understand and see your point. I saw so much that it all became "words" with no meaning. My hope, a dream really, was someone, within all the bs, had said something I could look at take seriously. The good and bad about this forum, say compared to the Ferrari Forum, is within "seconds" it appears everyone in the U.S. (in this case seldom are their participants from other countries for obvious reasons) have chimed in making any thread another lengthy expression of everyones need to opine. On the other hand, who am I to throw stones given the glass house I am living in. Best
#2078
Burning Brakes
Yup - I bet there are fewer than 20 Z06 owners who can drive truly fast, as in within say 2 sec a lap of Milner or Pobst. They probably lament the lack of cooling. But I think I read that over 8000 Z's were sold for the 2015 model year. That is more than the entire production of Ferrari. Seems like the right call by GM to just sort of fade all the track-worthiness questions.
#2079
Tech Contributor
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"Ask Tadge" Producer
I wouldn't be so quick to write GM off regarding this topic. While I have no details or specifics yet, I do know they're looking into it. Whether they're able to come up with an explanation or solution or not is another thing entirely. And it may be best to hand this off to the aftermarket (see: DeWitt).
#2080
Melting Slicks
I wouldn't be so quick to write GM off regarding this topic. While I have no details or specifics yet, I do know they're looking into it. Whether they're able to come up with an explanation or solution or not is another thing entirely. And it may be best to hand this off to the aftermarket (see: DeWitt).
That being said I hope that GM has a solution ASAP; (and frankly IMHO it only needs a secondary EOC), which we will be able to purchase as an 'off road' item at my Chevy dealer that is warrantied. I even want GM to make some profit on it as long as it performs the functions we want which is to markedly lower the engine oil temps, and then by extension the water temps so that this car can then run 25-30 minute sessions in the hands of an amateur on track in the Advanced run group.
Bish