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I've asked you this many times but how significant of an effect did it have on your ECT's? I still haven't seen ECTs over 190 with this new setup even while doing 85 up a hill on the interstate with the AC on.
I've asked you this many times but how significant of an effect did it have on your ECT's? I still haven't seen ECTs over 190 with this new setup even while doing 85 up a hill on the interstate with the AC on.
The biggest difference is down the interstate.....187 to 192. Before the heat exchanger pushed the air out of the way and lack of air deflector had it all over the place. Was around 205 to 214 at 75 to 80mph on 90 to 98 degree days.. I'm still going to upgrade the radiator and have a separate trans cooler. I replaced the thermostat to the larger opening of the 2 available.
The biggest difference is down the interstate.....187 to 192. Before the heat exchanger pushed the air out of the way and lack of air deflector had it all over the place. Was around 205 to 214 at 75 to 80mph on 90 to 98 degree days.. I'm still going to upgrade the radiator and have a separate trans cooler. I replaced the thermostat to the larger opening of the 2 available.
I would consider that significant. I think mine must be closer to stacked than it looks like in the picture. Even when my fan wasn't kicking on I wasn't getting hot as long as the car was rolling. I was recently told on facebook that because of a piece of sheet metal I have running on the bottom of my front mount to the rear of my radiator that I will have even more cooling problems. I thought running without a working fan or going down interstate 85 mph with AC on a hot day would be a decent indicator but apparently it's not. People look at one picture of my rigs and tell me it won't work but when empirical evidence says otherwise I will side with reality until it doesn't. Basically I'm not going to change my setup if all the indicators point to it actually working just because internet strangers anecdotal evidence. Unfortunately it will take a day at the track with the gopro rolling on my ECT the whole time to convince people that my cooling system actually works fine. I will say that based on what people have told me, such as your experience here, it does seem to be working better than it should. I'm sure there are other little variables that are affecting it as well. Do oil coolers help lower engine temps at all? That could be part of the reason I'm seeing even lower temperatures than last year. Last year same interstate situation I would be at 195-200.
My recent work over the last few months.
Wrap is Satin Pearl White with Gloss Green Envy stripes. Engine powdercoat is Illusion Money green.
I posted pics of the engine parts when I got them back from powdercoat, it was mentioned that the fuel rail internals may not of survived. Well they have been working properly for nearly 2500km now.
Looks good but you dont drive around with those headlight covers on at night do you? lol
Looks good but you dont drive around with those headlight covers on at night do you? lol
LoL, I don't drive around at all with them on anymore. I just put them on to cover up the water filled headlights I have on the car until my others are rebuilt.
Interstate test at 85mph (speedo 5% slow due to tires and general error, gps verified), uphill, and with the AC on while ambient temp is 92 degrees and humid. This is for all the people telling me I increased the ECT's with both my bottom baffle plate as well as intercooler mount location. Real world data>internet's assumptions based on anecdotal evidence. It was a 92-95 degree day and the highest ECT I saw was 185 and that was while cruising at 93 mph keeping up with the caravan for a while.
^ most people weren't saying you would adjust things at cruise speeds, even at cruising load you're not stressing anything. I saw the thread on FB and Johns responses are related to road racing, thats when you'll stress the cooling system. If you don't see elevated temps during your auto-x events then perfect the modifications don't effect your cooling enough to make a difference in those events, but just be ready if you get into road racing to watch the temps.
^ most people weren't saying you would adjust things at cruise speeds, even at cruising load you're not stressing anything. I saw the thread on FB and Johns responses are related to road racing, thats when you'll stress the cooling system. If you don't see elevated temps during your auto-x events then perfect the modifications don't effect your cooling enough to make a difference in those events, but just be ready if you get into road racing to watch the temps.
The efficiency of the system will correlate. It's not like road racing takes place where the laws of heat transfer and thermodynamics are different. If my cooling system increased efficiency (from stock) on the road why would it decrease the efficiency on road course? That doesn't make any sense. I would also argue that doing 85 down the interstate with the AC on is a decent load (though not road course levels) as others have high coolant temps on stock systems in those conditions. I have also tested the system without the fan on at all and the coolant temps were great as long as I was rolling. This also indicates a healthy natural airflow. The only point I am trying to make is I have not hindered the cooling system in any way. How can anyone say I have?
Also I NEVER made any claims about road racing. The car is setup for autocross. I posted in an Autocrossing & Road racing thread. John said my "Your ECT's will go up with that setup, Oh well" and after that is when John started saying "Oh well autocross isn't fast racing.... won't work on road course" even though I never made any claims or even mentioned road course racing. John straight up just said I would have higher ECT's to start and that is just flat out inaccurate. I know he knows his **** and have followed his opinions many times and have bought a lot of his parts but he doesn't know everything about everything in every scenario so well that he can look at one picture and tell me my ECT's will increase definitely. There are more than 2 factors when it comes to the fluid dynamics of the cooling system. No one could tell me what specifically about my system would hinder airflow. All they did was list examples of other cars with different setups and what happened there.
The efficiency of the system will correlate. It's not like road racing takes place where the laws of heat transfer and thermodynamics are different. If my cooling system increased efficiency (from stock) on the road why would it decrease the efficiency on road course? That doesn't make any sense. I would also argue that doing 85 down the interstate with the AC on is a decent load (though not road course levels) as others have high coolant temps on stock systems in those conditions. The only point I am trying to make is I have not hindered the cooling system in any way. How can anyone say I have?
No going 85mph is completely different than going WOT for 20-30mins on a road course. You just proved it wouldn't affect the cruising heating load, AC is not a decent load by any means.
There is a reason OEMs test the cooling system on tracks, it's the only way to stress them. Cruising at 85mph is consuming 3-4lb/min of air and fuel at stoich, cylinder temps are mild but some heat is being removed by the cooling system. At WOT I'm going to assume you're flowing 20-25lb/min of air and enough fuel to burn rich to help with cylinder cooling by excess fuel evaporation. The heat generated from WOT is significantly different than what is generated at cruising speeds.
Logging the coolant temps during a auto-x would indicate more than cruising, but to formulate a proper conclusion you need to monitor the temps using just the engine coolant sensor, you need pre and post radiator temp measurements and coolant flow measurements. Then if you can calculate based on heat capacities how much heat the radiator is taking out then make an extrapolation from there to determine when the unit will be overcome.
In the Camaro Z28 they literally hollowed out the bowtie to flow more air into the radiator during racing, it wasn't for cruising speeds.
No going 85mph is completely different than going WOT for 20-30mins on a road course. You just proved it wouldn't affect the cruising heating load, AC is not a decent load by any means.
There is a reason OEMs test the cooling system on tracks, it's the only way to stress them. Cruising at 85mph is consuming 3-4lb/min of air and fuel at stoich, cylinder temps are mild but some heat is being removed by the cooling system. At WOT I'm going to assume you're flowing 20-25lb/min of air and enough fuel to burn rich to help with cylinder cooling by excess fuel evaporation. The heat generated from WOT is significantly different than what is generated at cruising speeds.
Logging the coolant temps during a auto-x would indicate more than cruising, but to formulate a proper conclusion you need to monitor the temps using just the engine coolant sensor, you need pre and post radiator temp measurements and coolant flow measurements. Then if you can calculate based on heat capacities how much heat the radiator is taking out then make an extrapolation from there to determine when the unit will be overcome.
In the Camaro Z28 they literally hollowed out the bowtie to flow more air into the radiator during racing, it wasn't for cruising speeds.
So absolutely no correlation between cruising airflow and road course airflow? How could airflow increase while cruising and do the opposite while on road course? The point of stating that I am running the AC is I am heating the air via the condenser before it flows through the radiator not that it drags on the engine real hard.
I will say again I never made claims about superior performance on road course. The ONLY point I am trying to make is I did not hinder the performance compared to stock.
Also I NEVER made any claims about road racing. The car is setup for autocross. I posted in an Autocrossing & Road racing thread. John said my "Your ECT's will go up with that setup, Oh well" and after that is when John started saying "Oh well autocross isn't fast racing.... won't work on road course" even though I never made any claims or even mentioned road course racing. John straight up just said I would have higher ECT's to start and that is just flat out inaccurate. I know he knows his **** and have followed his opinions many times but he doesn't know everything about everything in every scenario so well that he can look at one picture and tell me my ECT's will increase definitely. No one could tell me what specifically about my system would hinder airflow. All they did was list examples of other cars with different setups and what happened there.
The page is road racing and auto-x most people think about what they do the most, John doesn't auto-x a lot.
You need to generate a significant amount of data before you make conclusions. John worked with the GM team on the Cobalt, he bases his information on what they discovered. You start adding pieces and then you start messing with the aerodynamics and air flow around the car. Without a DEM software and a proper model mockup it's difficult to explain the different effects that can occur, John maybe generalizing but overall he's correct, the majority of the heat from the radiator exits the car below the engine. Stacking extra radiators in front of the stock unit does decrease airflow to the main radiator. Also the front heat exchanger increases the air temp by 3-5*F (I'm guessing to lazy to calculate out the estimated temp increase for a given radiator) that decreases the amount of heat the radiator can loose since the incoming air is hotter.
So absolutely no correlation between cruising airflow and road course airflow? How could airflow increase while cruising and do the opposite while on road course?
I will say again I never made claims about superior performance on road course. The ONLY point I am trying to make is I did not hinder the performance compared to stock.
You're not maxing the system at cruise, therefore the system has excess cooling capacity. This is getting into thermodyanmics and the heat transfer available for a given system.
The page is road racing and auto-x most people think about what they do the most, John doesn't auto-x a lot.
You need to generate a significant amount of data before you make conclusions. John worked with the GM team on the Cobalt, he bases his information on what they discovered. You start adding pieces and then you start messing with the aerodynamics and air flow around the car. Without a DEM software and a proper model mockup it's difficult to explain the different effects that can occur, John maybe generalizing but overall he's correct, the majority of the heat from the radiator exits the car below the engine. Stacking extra radiators in front of the stock unit does decrease airflow to the main radiator. Also the front heat exchanger increases the air temp by 3-5*F (I'm guessing to lazy to calculate out the estimated temp increase for a given radiator) that decreases the amount of heat the radiator can loose since the incoming air is hotter.
The opening for the air to exit from underneath is not blocked off in any way!
John may have seen setups with similarities to mine but I don't think anyone had this exact setup. Also, look at this picture and tell me how I am hindering bottom evacuation of air from the radiator. My plate does not extend beyond the rear of the radiator.
You're not maxing the system at cruise, therefore the system has excess cooling capacity. This is getting into thermodyanmics and the heat transfer available for a given system.
Steady state temperatures definitely can indicate an improvement in airflow regardless of load. If steady state temperature under similar conditions is lower than before the addition that indicates higher efficiency.
09-18-2017 | 01:12 AM
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