Intercooler Behind Firewall?
#1
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Has anyone mounted their intercooler in the passenger compartment? I'm selling the aluminum sheet metal intake manifold (ebay item #170446547871) from my FWD Escort (BP powered) and thought to myself "hey this would go great with a cockpit mounted IC in a miata track car". The only problem is that I haven't personally seen or heard of anyone running a setup like that in a miata. It's pretty common in high horsepower turbo and supercharged mustangs as pictured below. Just curious if any miatas have run a similar setup. It would be a great way to improve the center of gravity.
Greg Michalski 1993 Mustang 88mm single turbo
![](http://www.horsepowerconnection.com/CustomersCars/GregMichalski/DCP_2118.JPG)
Greg Michalski 1993 Mustang 88mm single turbo
![](http://www.horsepowerconnection.com/CustomersCars/GregMichalski/Cobra%20010%20(Small).jpg)
#5
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Not many cars do. Just putting it out there.
I'm converting to a top mount air to water setup on my car to shorten my charge piping from about 7 feet to about 14 inches total. I'm hoping it'll help a little in the lag department with the big turbo that's going in.
Here is a link to the intake. Looking at it again, it's probably too tall for a miata so it's not really relevant.
Mazda BP sheet metal alumunim intake manifold : eBay Motors (item 170446547871 end time Feb-21-10 18:30:08 PST)
I'm converting to a top mount air to water setup on my car to shorten my charge piping from about 7 feet to about 14 inches total. I'm hoping it'll help a little in the lag department with the big turbo that's going in.
Here is a link to the intake. Looking at it again, it's probably too tall for a miata so it's not really relevant.
Mazda BP sheet metal alumunim intake manifold : eBay Motors (item 170446547871 end time Feb-21-10 18:30:08 PST)
#6
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Water/air set ups are very common to drag racing, and if you do not have one in a competitive class, you can forget about winning.
Water/air is not practicle for road racing, because it does not take long for the water to get too hot to be benificial. Drag racers use a mixture of ice and water, and the water temps come close to luke warm after just one run.
Water/air is not practicle for road racing, because it does not take long for the water to get too hot to be benificial. Drag racers use a mixture of ice and water, and the water temps come close to luke warm after just one run.
#7
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In a turbocharged application, non-throttled volume between the compressor and manifold is nearly irrelevant. It's an interesting packaging solution in what is obviously a space-constrained install, however I concur with my colleagues that for nearly(*) anything other than a dedicated autocross or drag car, the front-mounted air to air intercooler is far and away the most effective solution. And even for drag and autocross vehicles, if the rules permit carrying an ice chest, then they probably permit carrying a tank of liquefied CO2 as well.
(*) The one street application where I will concede to the benefits of a W/A design is when a positive-displacement supercharger is installed in a single-throttle configuration. In this case, the advantage of being able to idle outweighs the added complexity and inferior performance relative to an A/A design.
#9
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Unlikely.
In a turbocharged application, non-throttled volume between the compressor and manifold is nearly irrelevant. It's an interesting packaging solution in what is obviously a space-constrained install, however I concur with my colleagues that for nearly(*) anything other than a dedicated autocross or drag car, the front-mounted air to air intercooler is far and away the most effective solution. And even for drag and autocross vehicles, if the rules permit carrying an ice chest, then they probably permit carrying a tank of liquefied CO2 as well.
In a turbocharged application, non-throttled volume between the compressor and manifold is nearly irrelevant. It's an interesting packaging solution in what is obviously a space-constrained install, however I concur with my colleagues that for nearly(*) anything other than a dedicated autocross or drag car, the front-mounted air to air intercooler is far and away the most effective solution. And even for drag and autocross vehicles, if the rules permit carrying an ice chest, then they probably permit carrying a tank of liquefied CO2 as well.
(*) The one street application where I will concede to the benefits of a W/A design is when a positive-displacement supercharger is installed in a single-throttle configuration. In this case, the advantage of being able to idle outweighs the added complexity and inferior performance relative to an A/A design.
#10
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I would suggest that shortening up the IC tubes is not a useful endeavor. Figure out how to calculate the time delay of pumping through longer tubes. That will determine the time delay. I would suggest that the IC mounted in the next county will not delay boost response. The air moving through the system moves so bloody fast that distance means little.
Please keep in mind it is not necessary to pressurize the entire system to the max before boost arrives in the combustion chamber. The pressure applied at one end is immediately( or bloody close) felt at the other. They sort of "well up" in rapid sequence. To get an idea of that amount of time, calculate the velocity of the air in the tube. It is the cfm divided by the area of the tube. Remember to get all the inches to feet and seconds to minutes right.
The cfm used must be the flow rate at the time the throttle is mashed.
Then estimate the distance from turbo to intake valve and divide the distance by the velocity and time in seconds should fall out as how long it takes a molecule to get from the turbo to the intake valve at those conditions.
I'd hock my third born for a blender that quick.
The cfm used must be the flow rate at the time the throttle is mashed.
Then estimate the distance from turbo to intake valve and divide the distance by the velocity and time in seconds should fall out as how long it takes a molecule to get from the turbo to the intake valve at those conditions.
I'd hock my third born for a blender that quick.
#14
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Big time! I've seen a back window blown out of an NMRA car on the top end at 160+ mph when a coupling let loose; took 30 minutes to clean all the glass of the track. Another NMRA racer had a weld on an intercooler seam burst at over 35psi and said the concussion wave in the car was like an artillery shell.
#15
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Yeah it really would suck to lose your hearing in that situation.
I'm a huge proponent to air:water charge cooling, and its really interesting how many people (especially those with Sy/Ty experience) say air to air is so much better..
The Syclone/Typhoon IIRC was a failure in the air to water department because it used the vehicles engine coolant through the heat exchangers. Brilliant idea, GM.. I know a lot of retard owners that took the saw to their truck for a frontmount instead of using their brain and making their current system standalone and more efficent.![facepalm](https://www.miataturbo.net/images/smilies/facepalm.gif)
In my opinion if you have enough water in your system, a good pump, and large efficent heat exchanger I don't see anything short of maybe bonneville that could heat up a large volume of water to the point of losing effectiveness as a charge air cooler.. However I could be wrong. . .
I'm a huge proponent to air:water charge cooling, and its really interesting how many people (especially those with Sy/Ty experience) say air to air is so much better..
The Syclone/Typhoon IIRC was a failure in the air to water department because it used the vehicles engine coolant through the heat exchangers. Brilliant idea, GM.. I know a lot of retard owners that took the saw to their truck for a frontmount instead of using their brain and making their current system standalone and more efficent.
![facepalm](https://www.miataturbo.net/images/smilies/facepalm.gif)
In my opinion if you have enough water in your system, a good pump, and large efficent heat exchanger I don't see anything short of maybe bonneville that could heat up a large volume of water to the point of losing effectiveness as a charge air cooler.. However I could be wrong. . .
#16
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Eli? Is that you?
Well, consider this.
I agree that a well-designed W/A system can be made to operate efficiently in most street or track aplications, assuming that one uses a dedicated water tank which is separate from the engine's cooling system, a pump with a sufficiently high flowrate, and a forward exchanger with a sufficiently large area.
What I fail to see is where a system like that would have any advantage over a conventional front-mounted air-air intercooler. The water-air setup we've described will certainly cost much, much more, it will be far heavier, it will occupy a great deal of space, it will be more complex, and it will be more failure-prone insomuch as that it has moving parts, requires electricity (or a belt) to operate, and is intolerant of even tiny leaks.
So in exchange for all this, you get a system which, at best, works just as well as a properly-designed A/A system which is cheap, lightweight, compact, passive, reliable, and tolerant of small leaks.
Clearly I am missing something.
I agree that a well-designed W/A system can be made to operate efficiently in most street or track aplications, assuming that one uses a dedicated water tank which is separate from the engine's cooling system, a pump with a sufficiently high flowrate, and a forward exchanger with a sufficiently large area.
What I fail to see is where a system like that would have any advantage over a conventional front-mounted air-air intercooler. The water-air setup we've described will certainly cost much, much more, it will be far heavier, it will occupy a great deal of space, it will be more complex, and it will be more failure-prone insomuch as that it has moving parts, requires electricity (or a belt) to operate, and is intolerant of even tiny leaks.
So in exchange for all this, you get a system which, at best, works just as well as a properly-designed A/A system which is cheap, lightweight, compact, passive, reliable, and tolerant of small leaks.
Clearly I am missing something.
#17
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The benefit would be more consistent charge cooling at low speeds.
Take an autoX for instance, where you will not spend too much time north of 60 MPH in a lot of cases. You have a lot of time in doing about 30-40. Quite aside from the possibility of simply loading up on ice cold fluid for a run, you will have very good cooling just from the thermal mass of the water even with a pretty small system. The low airflow levels over the A/A IC might be hindering its effectiveness in the same situation. And high flow pumps that will move more water than nessesary are cheap and readily avilable as well as pretty reliable. Shoot there are aquariium pumps that will move several gallons per minute that last for years. With a proper heat exchanger (maybe a Honda Civic radiator?) such a pump may well do great. If you want to go baller, an electronic water pump for a small-block would be great. Or just ice box it. With the power levels and heat created by any of the setups here, such a system will easaly last a full run.
I do agree that you will get very little in the way of lag reduction by reducing piping. Shoot, people have generally shown that huge FMICs dont actually affect spool time much and thats much more of a internal volume difference than a foot of 2.5" pipe.
But I dont wonder about overall flow with shorter piping. Runner length and cleaning up the throat of the intake manifold seems to make a sigificant difference due to less of a restriction. Could the same not also be said of a very low restriction yet thermaly efficient IC?
Honestly I think water/meth and a decent A/A is the way to go, but if yu have a say a highly competitive autoX car that needs some ballast weight, this might be a really good idea.
Take an autoX for instance, where you will not spend too much time north of 60 MPH in a lot of cases. You have a lot of time in doing about 30-40. Quite aside from the possibility of simply loading up on ice cold fluid for a run, you will have very good cooling just from the thermal mass of the water even with a pretty small system. The low airflow levels over the A/A IC might be hindering its effectiveness in the same situation. And high flow pumps that will move more water than nessesary are cheap and readily avilable as well as pretty reliable. Shoot there are aquariium pumps that will move several gallons per minute that last for years. With a proper heat exchanger (maybe a Honda Civic radiator?) such a pump may well do great. If you want to go baller, an electronic water pump for a small-block would be great. Or just ice box it. With the power levels and heat created by any of the setups here, such a system will easaly last a full run.
I do agree that you will get very little in the way of lag reduction by reducing piping. Shoot, people have generally shown that huge FMICs dont actually affect spool time much and thats much more of a internal volume difference than a foot of 2.5" pipe.
But I dont wonder about overall flow with shorter piping. Runner length and cleaning up the throat of the intake manifold seems to make a sigificant difference due to less of a restriction. Could the same not also be said of a very low restriction yet thermaly efficient IC?
Honestly I think water/meth and a decent A/A is the way to go, but if yu have a say a highly competitive autoX car that needs some ballast weight, this might be a really good idea.