Would make sence on a N/A car but after the supercharger and increase in pressue temps will rise.
As presure goes up... Tempature goes up.
As presure goes up... Tempature goes up.
COLD AIR INDUCTION WORTHLESS ON 03 COBRA
- Thread starter Fast03Cobra
- Start date
Water Wetter
I drew the following conclusions from cooling expirences with my two Ducati Racebikes (998R, 748R). I would think cooling is cooling.
Removing the fans from behind the radiator reduced water temp by 5 deg. Radiator can flow more air with nothing behind it. A fan only helps when you are not moving.
By using one bottle of Water Wetter for every gallon of water I reduced water temp another 8 deg.
I hope this may help.
sqidd
:xpl: this little guy is great
I drew the following conclusions from cooling expirences with my two Ducati Racebikes (998R, 748R). I would think cooling is cooling.
Removing the fans from behind the radiator reduced water temp by 5 deg. Radiator can flow more air with nothing behind it. A fan only helps when you are not moving.
By using one bottle of Water Wetter for every gallon of water I reduced water temp another 8 deg.
I hope this may help.
sqidd
:xpl: this little guy is great
One thing about that small fan. Exactly how much will you gain?
PROS:
Cooling
More HP (how much)
CONS:
More wieght
More pull on the Alternator = more friction = less free HP to the rear!
Not sure we can gain much there...Dunno
PROS:
Cooling
More HP (how much)
CONS:
More wieght
More pull on the Alternator = more friction = less free HP to the rear!
Not sure we can gain much there...Dunno
There are some Lightning owners who have installed small fans behind their heat exchangers, and some who have increased the size of the heat exchanger.
As someone pointed out, the fan is really only going to help if you are sitting still...or maybe in the staging lanes with the motor off, but fan running.
<---so if its a "track only" type item, then you might as well consider dumping ice water in there at the track. Save the cost, weight, drain on the alternator that the fan will bring.
I _know_ this is what Muscle Mustangs/Fast Fords has done with their Lightning, and I believe this works well.
As someone pointed out, the fan is really only going to help if you are sitting still...or maybe in the staging lanes with the motor off, but fan running.
<---so if its a "track only" type item, then you might as well consider dumping ice water in there at the track. Save the cost, weight, drain on the alternator that the fan will bring. I _know_ this is what Muscle Mustangs/Fast Fords has done with their Lightning, and I believe this works well.
I'm an engineer, and while thermodynamics was never my strongest subject, I'm going to take a stab at this anyway.
I doubt a larger intercooler system would help very much except on a race car which is running at high boost almost continuously. The rate of heat transfer between two fluids (air is considered a fluid) increases as the temperature differential increases. During "spirited" street driving I doubt the air gets hot enough that the intercooler can function very efficiently.
Remember also that air is an excellent thermal insulator, and it is very difficult to cool air just by blowing it over a heat exchanger (especially when the air temperature isn't that much higher than the coolant temp). That's why your cars have A/C systems with compressors, etc. instead of just an "intercooler".
As for the CAI, I would be skeptical of any claims of large HP increases. However, all other things being equal, the cooler the air entering the supercharger, the cooler it should be on exit, even after being heated by being compressed.
I think I agree with that logic.
I was told by a Z06 owner at the track, to run my defroster on high with the heat on to:
1. Disipate heat built up from the 1/4 mile run.
2. Causes the AC compressor to run and thus the fan which should cool off the coolant, etc...
The Z06 has temp gauges that are functional and meaningful (unlike the 03 Cobra). He claims it REALLY bleeds off a lot of heat and cools him to a 194F coolant temp. He does "hot runs" and just runs one lap after another without cooling off with consistent 12.2's...
Dunno if it worked on the Cobra, but my azz was sure sweaty!
WE need some coolant temp and oil temp gauges. They boned us on that with the 03 Cobra IMHO..
I was told by a Z06 owner at the track, to run my defroster on high with the heat on to:
1. Disipate heat built up from the 1/4 mile run.
2. Causes the AC compressor to run and thus the fan which should cool off the coolant, etc...
The Z06 has temp gauges that are functional and meaningful (unlike the 03 Cobra). He claims it REALLY bleeds off a lot of heat and cools him to a 194F coolant temp. He does "hot runs" and just runs one lap after another without cooling off with consistent 12.2's...
Dunno if it worked on the Cobra, but my azz was sure sweaty!
WE need some coolant temp and oil temp gauges. They boned us on that with the 03 Cobra IMHO..
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Running the heat should definitely aid engine cooling, but if anything I would expect the AC compressor to hurt, not help...
I would agree that running the heat definetely will cool your car down because a fan is blowing over a heating element feed by the engine cooling system. That is why on a cold day it might take a couple of blocks for your heat to get hot the engine is still warming up. If you are a hardcore race fan you could probably run your car with the heat on while racing to provide extra cooling. I don't think the AC compressor is turned on there is no reason for it to be running with the heater on there functions are completely opposite.
The best the IC on the '03 can do is reduce the intake air temperature to ambient.
Assuming that the factory IC is sufficiently sized to always bring the intake air to ambient under factory boost levels, then we may assume the CAI will have no effect (the intake air will unltimately get to the same ambient temps anyway).
Now, what happens when we open up the filter element (K&N mounted directly to MAF)? Postban posted temperature differentials between airbox interior temps and underhood temps of 67 degrees.
Can the factory IC reduce these higher intake air temp to ambient under factory boost levels?
If the factory IC is sufficiently sized to lower these elevated intake air temps to ambient, this is all moot anyway. Until someone tests each condition, we will not know.
What happens if we raise boost levels, therefore, increase heat due to more compression?
Assuming that the factory IC is sufficiently sized to always bring the intake air to ambient under factory boost levels, then we may assume the CAI will have no effect (the intake air will unltimately get to the same ambient temps anyway).
Now, what happens when we open up the filter element (K&N mounted directly to MAF)? Postban posted temperature differentials between airbox interior temps and underhood temps of 67 degrees.
Can the factory IC reduce these higher intake air temp to ambient under factory boost levels?
If the factory IC is sufficiently sized to lower these elevated intake air temps to ambient, this is all moot anyway. Until someone tests each condition, we will not know.
What happens if we raise boost levels, therefore, increase heat due to more compression?
I actually wrote on this topic for Nutz and Boltz, but from the other side - it was for an article on "how to get your car to warm up faster on a cold day".
Running the defroster above a certain temp cuts on the compressor - this will pre-heat the air entering the radiator and warm up the coolant and provide heat faster.
For track benefits, you want to run the Heater, not the defroster. It acts as a little radiator, since that is what the core is - a little rad. In heater mode, the compressor is not engaged, and the resultant heat from the thermotropic exchanges will not work against you.
Amazing how a thread can get it nearly 100% right, but miss it by a hair. Good stuff though, I like these threads.
Running the defroster above a certain temp cuts on the compressor - this will pre-heat the air entering the radiator and warm up the coolant and provide heat faster.
For track benefits, you want to run the Heater, not the defroster. It acts as a little radiator, since that is what the core is - a little rad. In heater mode, the compressor is not engaged, and the resultant heat from the thermotropic exchanges will not work against you.
Amazing how a thread can get it nearly 100% right, but miss it by a hair. Good stuff though, I like these threads.
I doubt even an aftermarket intercooler would cool the air to ambient temperature under boost. That would require perfect efficiency, which nothing possesses in the real world.
I agree this usually happens for 'marketing', but I have seen many other posts here to support the power increases claimed by the manufacturer. Besides, if they 'forgot' to mention a pulley change, the dyno numbers would be higher. I guess to only way to 'prove' the numbers would be a video of the dyno session with accountants from Price Waterhouse supervising to verify its authenticity......
No I just trust my experience, knowledge, and the finding of select individuals.
Posting "The dyno sheets don't lie......." does not state any opinion or facts about cold air kits, it only states you believe dyno sheets. What dyno sheets are you referring to?
Btw I have seen several dyno sheets showing loss of power for cold air kits.
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To me, the above post makes the most sense.
Here is the way I look at it.
To begin, we must acknowledge that the supercharger on the Cobra is not an ideal adiabatic compressor. In other words, it is adding heat to the air. In simple terms, the job of the intercooler is to remove this heat(which also serves to increase density, which is good). The problem is, a typical intercooler will have an efficiency of only 60 - 80%. I admit that I do not know the exact efficiency of the '03 IC, but for the sake of argument we can assume 70%. This being true, then one way to reduce heat in the intake charge is to reduce the temperature of the air being drawn into the blower itself. This is where a "Cold Air Intake"(CAI) becomes handy. It is a proven concept, that reducing the temperature of the air prior to entering the blower is beneficial. Mainly because, and once again, the intercooler efficiency is not 100%. Thus any initial decrease in the temperature of the air(prior to entering the blower) will serve to keep the final temperature lower. This is proven science.
Now, there are a few other things to consider that can help cool the air other than a CAI. The efficiency of the intercooler is in part determined by the overall surface area of the core. The required surface area to adequately cool the air can actually be determined, if given information about the engine and blower. If the current IC's surface area is determined to be inadequate to a statistically significant measure in terms of surface area, then by increasing this surface area via a larger core will in fact help in creating more power. This is also proven science. There are some problems associated with doing this though, and these must be considered(room, cost etc).
Also, one might consider N20. This will have the effect of supercooling the intake charge while creating more hp. This can have dramatic positive effects on turbo and blown engines. There are also issues that need to be addressed with this solution.
Bottom line, there is proven science that by reducing the temperature of the air prior to entering the blower will have an overall beneficial effect, mainly because the intercooler is not 100% efficient in cooling the air.
Mordeth
No, actually the Z06 guy had it right. The best way to cool a car engine down is with the ac compressor running and the vent set to high heat.
1) If the car has electric coolant fans they will kick on when the compressor comes on.
2) the evaporator in the dash immediately cools the vent air down before it passes over the heater core, which is where coolant heat it exchanged to the vent air.
I agree, I think it should be stated that this is with the engine not running, If the engine is running it will certainly make more heat, and with the drag of the a/c compressor, even that much more heat. With just the ignition on, (and a/c on) the electric fan will run (for the condensor) it just so happens that this also cools the water in the radiator, since they are right next to each other, and the blower inside the car will remove heat from the heater core. So when you start your engine the next time, you have cooler water in the radiator, and cooler water in the heater core, which will then cool the engine as well.
Couple of things. I still think the AC running helps more than it hurts. It has maybe a 7HP drain/load on the engine. If we assume we are on average 370 RWHP thats 425 at the flywheel and the 7 HP load is a very small load on this engine. Not going to produce that much heat. BUT the defroster forces the AC to run which forces the fan to run. Turning on the water/heat forces radiator fluid through the heater core (another smaller radiator).. NOW you have the following situation:
1. Main engine fan running and cooling the radiator coolant, engine oil, IC coolant, engine compartment, etc...
2. Cold AC air running across the heater core which is also helping to cool the coolant.
Just the heat alone does not force the main fan to run nor does it force COLDER air across the heater core.
--------------------------
Now back to the MAIN reason for the thread. Cold Air Induction.
I have made the logical decision TODAY to:
A. re-install my air silencer.
B. install a K&N filter.
I figure this is the BEST bang for the buck. I get a larger element than the one in the fender, and I am still drawing cooler air from the fender well via silencer, and I have a filter that flows at a higher CFM than the stock paper element.
Until we can prove conclusively that another system works THAT MUCH better, I'm sticken with my current setup....
Thanks for all the GREAT information, debate, posts, what have you... VERY VERY informative and we ALL kept things on a very civil level. Nice job!
Now to have a similar discussion about exhaust systems...
1. Main engine fan running and cooling the radiator coolant, engine oil, IC coolant, engine compartment, etc...
2. Cold AC air running across the heater core which is also helping to cool the coolant.
Just the heat alone does not force the main fan to run nor does it force COLDER air across the heater core.
--------------------------
Now back to the MAIN reason for the thread. Cold Air Induction.
I have made the logical decision TODAY to:
A. re-install my air silencer.
B. install a K&N filter.
I figure this is the BEST bang for the buck. I get a larger element than the one in the fender, and I am still drawing cooler air from the fender well via silencer, and I have a filter that flows at a higher CFM than the stock paper element.
Until we can prove conclusively that another system works THAT MUCH better, I'm sticken with my current setup....
Thanks for all the GREAT information, debate, posts, what have you... VERY VERY informative and we ALL kept things on a very civil level. Nice job!
Now to have a similar discussion about exhaust systems...
1) Yes, I agree to what you said, but the condenser in front of the radiator is hot, and the air those fans are pulling in will be the ambient air temp + the heat exchanged from the condenser. It becomes a volume/velocity issue, and I have to believe that the total BTU's added will be far greater than those removed by a cool a/c charge blowing over the little heater core.
2) The fans after a hot run will be on anyway, likely on high in the hot staging area, plus if you have a chip, they will likely be calibrated to come on sooner.
Mosconiac post makes sense, but it still comes down to whether a bigger gulp of hi velocity air from the straight ahead air inlet will result in better breathing than the fenderwelled approach.
One thing not clear from Postban is how fast the thermocouple responds - does it have a lag which would be longer than the actual air temp drop right in front of the car?
Well, I don't know how you reached these conclusions from this thread.
1) The AC thing is a big mistake. The main thing that determines what temperature the car runs at is the thermostat. You can leave the A/C run all you want, if the rad gets cold , the thermostat will just close off. Like '03 Cobra said, all you are doing is making the condensor core in front of the radiator hot.
2) The silencer is a major restriction, verified by millions of people around the world. J/K
Well, just kidding about the millions of people part, it's probably only thousands.
The best bang for the buck is undoubtedly the K-0945 in the stock housing with the the silencer removed. The opening in the stock airbox faces the fender where it can pull cold air. The 4.5 length inches of 3.5" ID tube is just too restrictive for an engine that needs to pull 800+ CFM. Chew on this tidbit, 3.5 ID tube is 9.62 square inches, 800 CFM is 1,382,400 cubic inches/minute, which leaves a velocity of 143,700 inches/minute which is 136 mph, WOW, can that be right??? Someone check the numbers please!
JT
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