Drivetrain New R53 A2A Intercooler from DoS
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New R53 A2A Intercooler from DoS
Hi All,
With the our latest R56 Intercooler development now completed, we've turned our efforts back toward the R53.
What you see in the picture above is the product of realizing that:
1) Water-to-Air intercoolers (W2A-IC's) don't have super-stellar recovery time after heat soak (parked for an hour after a hard run) on street driven R53's. W2A-IC's are great for track driven R53's, but you need to allow a slightly longer time for recovery when on the street.
2) The R56 is a much better candidate for a W2A-IC on the street and at the track. (We used our R53 research as our baseline and the R56's recovery numbers kicked its butt at the track and on the street -- Sad but true.)
3) We always knew that the R53's intercooler is in a crappy location, but we needed a way to cool the charge air effectively while creating a completely reversible, easier-to-do mod.
4) The GP intercooler works great, but we've always thought that there was a way to use a smaller volume to do the same amount (or more) of charge cooling.
5) Removing your intercooler to do minor maintenance (like changing your plugs) is (more than) annoying at times.
With these factors in mind we put aside all our R53 W2A-IC fun and embarked on the path of Air-to-Air intercooling (A2A-IC). This took-up the better part of this summer, but it was well worth it.
We ended up building an A2A-IC that gave us the performance that we were looking-for with quick recovery on the street and track.
How did we do it?
A) We did a TON of materials and suppliers research and found that copper has a thermal conductivity of 231 Btu/hr/ft. Aluminum has a thermal conductivity of only 136 Btu/hr/ft. This means that copper can conduct heat 59% more efficiently than aluminum.
B) We fabricated several core designs using copper fins, copper turbulators, and brass tubes with a very high copper content (85%). The space available for the IC limited us slightly, but we created a core that outflowed and has less pressure drop than the stock A2A intercooler and the GP intercooler.
C)We did a major study of the stock A2A intercooler and GP intercooler to see why they both worked fairly well given their constraints. Matt Richter ("Dr. O" of MC2 fame) always likes to point out how the intercooler tubes are crimped in a way so that the air is ramped to minimize disturbance. However, I noticed there are 2 major areas of disturbance at the corners of the endtanks where the air does not flow smoothly (to ease manufacturing).
With the factors above in mind, DoS designed special endtanks that have airfoils at the entrance and exit to each tube to promote laminar airflow. We also made the end tanks out of a high performance, high-temp resistant, engineering plastic to create contoured airflow surfaces and minimize heat soak whererever possible.
In 100 degrees F conditions, initial datalogging is showing 5-10 degrees F above ambient at cruise and 20-30 degrees F above ambient under full load/boost. (Better than what we expected). As an added bonus, our copper A2A-IC recovers from parked heat soak & after heavy load/high boost conditions 60-to-75% faster than DoS's Gen III R53 W2A-IC kit and 35-to-45% faster than a stock A2A-IC.
Projected retail pricing is ~=$900.00-to-$1000.00
I'll keep you posted on the details. These are projected to start shipping in October.
-Clint
With the our latest R56 Intercooler development now completed, we've turned our efforts back toward the R53.
What you see in the picture above is the product of realizing that:
1) Water-to-Air intercoolers (W2A-IC's) don't have super-stellar recovery time after heat soak (parked for an hour after a hard run) on street driven R53's. W2A-IC's are great for track driven R53's, but you need to allow a slightly longer time for recovery when on the street.
2) The R56 is a much better candidate for a W2A-IC on the street and at the track. (We used our R53 research as our baseline and the R56's recovery numbers kicked its butt at the track and on the street -- Sad but true.)
3) We always knew that the R53's intercooler is in a crappy location, but we needed a way to cool the charge air effectively while creating a completely reversible, easier-to-do mod.
4) The GP intercooler works great, but we've always thought that there was a way to use a smaller volume to do the same amount (or more) of charge cooling.
5) Removing your intercooler to do minor maintenance (like changing your plugs) is (more than) annoying at times.
With these factors in mind we put aside all our R53 W2A-IC fun and embarked on the path of Air-to-Air intercooling (A2A-IC). This took-up the better part of this summer, but it was well worth it.
We ended up building an A2A-IC that gave us the performance that we were looking-for with quick recovery on the street and track.
How did we do it?
A) We did a TON of materials and suppliers research and found that copper has a thermal conductivity of 231 Btu/hr/ft. Aluminum has a thermal conductivity of only 136 Btu/hr/ft. This means that copper can conduct heat 59% more efficiently than aluminum.
B) We fabricated several core designs using copper fins, copper turbulators, and brass tubes with a very high copper content (85%). The space available for the IC limited us slightly, but we created a core that outflowed and has less pressure drop than the stock A2A intercooler and the GP intercooler.
C)We did a major study of the stock A2A intercooler and GP intercooler to see why they both worked fairly well given their constraints. Matt Richter ("Dr. O" of MC2 fame) always likes to point out how the intercooler tubes are crimped in a way so that the air is ramped to minimize disturbance. However, I noticed there are 2 major areas of disturbance at the corners of the endtanks where the air does not flow smoothly (to ease manufacturing).
With the factors above in mind, DoS designed special endtanks that have airfoils at the entrance and exit to each tube to promote laminar airflow. We also made the end tanks out of a high performance, high-temp resistant, engineering plastic to create contoured airflow surfaces and minimize heat soak whererever possible.
In 100 degrees F conditions, initial datalogging is showing 5-10 degrees F above ambient at cruise and 20-30 degrees F above ambient under full load/boost. (Better than what we expected). As an added bonus, our copper A2A-IC recovers from parked heat soak & after heavy load/high boost conditions 60-to-75% faster than DoS's Gen III R53 W2A-IC kit and 35-to-45% faster than a stock A2A-IC.
Projected retail pricing is ~=$900.00-to-$1000.00
I'll keep you posted on the details. These are projected to start shipping in October.
-Clint
Last edited by Mini'mon; 09-03-2010 at 03:49 PM.
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You only need to change the foam seal (on the plastic duct panel that mounts to the hood) to a new configuration that we've spec'd.
There will be some slight cosmetic changes on the production units that will have proper mating surfaces for the new foam seal configuration, but all else remains unchanged.
-Clint
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scolburn, it has a high content of copper, which is muuuch more expensive than aluminum. its not more expensive just because they think highly of themselves or anything, but it will mean that it probably will not sell in large numbers. But the people who want/need it will buy it.
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I'm an Electrician, you don't need to tell me about the price of copper Hell, i've got more than enough scrap copper in the back of my car at the moment to be able to make 10 of them!!! If only I could melt it down and send it to him!!! But I will take it and get some $$$$ for it. Also, I didn't once say they think highly of themselves or anything like that. I just said that with that price they might be pricing themselves out of it. But I will say that if it works as good as they say it does then people will pay the extra for it. Lets just hope, with some more data, that this blows everything out of the water
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We will have a heat dispersant coating option available to customers that want it.
Personaly I would like to see the same design cues you used (copper fins, brass tubes, and the airfoils) on a flow through design like M7's DFIC, That would be one that I would spend a grand on.
Nothing against your I/C, just dont care much for the 90 degree turn method of airflow.
Direct Flow Intercoolers are interesting, and we looked to see if this type of design could be of benefit. However, you always need to take into account 2 factors:
1) The second half of any intercooler core does only 1/4 of the the work. Air gets warmer as it gets deeper into the core. The front half of the core does a great job, but the back half of the core suffers due to progressively increasing air temps.
2) Even though the airflow is 'direct', because this is a very thick core, there's a great amount of drag on the cooling air passing through. The drag on the incoming air actually increases the deeper that you go into the core.
When an exit scoop is involved, the first factor can likely be somewhat minimized, but that involves some substantial cutting to bonnet sheet metal.
True, MINI's GP unit and DoS are both asking the air to take a tumble as it enters the intercooler (but turbulence is not always the enemy when you're trying to cool surfaces). Additionally, the fact that the core is 1/3-to-1/4 the thickness of a comparable direct flow intercooler, has greater frontal surface area, and more charge air channels means better performance.
Our R53 A2A-IC unit is 15 lbs lighter than a DoS R53 W2A-IC that's filled with coolant. The weight difference between the DoS A2A-IC + mounting hardware and the GP unit + mounting hardware + diverter is negligible.
OK, going to head out and enjoy some Labor Day Weekend fun.
Enjoy your day!
-Clint