Turbo kit using Innovate Air-2-Water Intercooler?

[Sellout]

Sigh. This is where a degree might help me explain this shit better. I don't have the vocabulary but transferring heat is how I make my living and understanding the physics involved luckily doesn't require me to be able to explain it so well...

Transferring heat from air to water isn't any less difficult than removing heat from water with air. The temperature differential is where the problem is. If you've got a big enough radiator, you don't need as much TD. If your radiator is big enough, your system will not heat soak on track. Period. The physics just don't support it.

The only problem is that everyone wants to act like the heat capacity of the water is the real beauty of the system instead of designing it to reject heat as well as it absorbs heat. That's all there is to it.

[sw20kosh]

Originally Posted by Sellout

Sigh. This is where a degree might help me explain this shit better. I don't have the vocabulary but transferring heat is how I make my living and understanding the physics involved luckily doesn't require me to be able to explain it so well...

Transferring heat from air to water isn't any less difficult than removing heat from water with air. The temperature differential is where the problem is. If you've got a big enough radiator, you don't need as much TD. If your radiator is big enough, your system will not heat soak on track. Period. The physics just don't support it.

The only problem is that everyone wants to act like the heat capacity of the water is the real beauty of the system instead of designing it to reject heat as well as it absorbs heat. That's all there is to it.

Us track guys (with turbos) are having problems with the stock coolant system heat soaking ... So having a a-w system with a large radiator is going to make things even worse on track for both engine coolant and supercharger coolant. This car suffers from lack of airflow through the front of the car and airflow out.

[iBoost]

If I understand correct, Sellout is referring to the fact that water has a MUCH higher thermal conductivity than air. This means it can transfer, ala "conduct," heat energy much faster either into or out of a medium.

So, this begs the question: What would be a good dual heat-exchanger design as shown in my first post (thickness, length, width, and core style) to keep the intake charge cool enough not to heatsoak? Each heat-exchanger "radiator" could be mounted in a slanted fashion to fit a thicker core if need be because they would have sealed air ducts anyways.

Secondary question: How much does this seibon hood scoop affect the car's Coefficient Of Drag? (this could be used with a topmount air-to-air intercooler as a plan B if need be:

[Calum]

Originally Posted by sw20kosh

Us track guys (with turbos) are having problems with the stock coolant system heat soaking ... So having a a-w system with a large radiator is going to make things even worse on track for both engine coolant and supercharger coolant. This car suffers from lack of airflow through the front of the car and airflow out.

What's the difference? Either way you're rejecting heat from a heat exchanger at the front of the radiator. And water conducting heat more easily means you could get away with less surface area to reject the same amount of heat.

[350matt]

I'd generally agree that in terms of heat rejection there's little to choose between an air / air and air/ water systems

however air/ air adds a lot of volume post throttle so it'll never be as good in terms of throttle response as an air/ water system

water also has a much higher specific heat capacity than air so it takes a lot longer to heat up
so for everyday driving / transients where you're rarely on the throttle for long periods your IAT is typically less that it will be for an air/air system

however if the water radiator is undersized and the pump is too small then yes it'll struggle to deal with extended periods of full throttle - but a well designed system shouldn't suffer from this

bear in mind Jaguar , mercedes etc all use water air systems

OEMS wouldn't add the extra complexity unless it was better for a road car

[Sellout]

Couple things:

I used to know a guy who used a FMIC, that was originally designed for air/air heat transfer, as the heat exchanger for his custom water/air setup. Obviously he had to figure out a way to make the end tanks work for water connection instead of air, but it worked perfectly. He was a track whore too. It never heat soaked specifically because he designed the system to be able to reject heat quickly. It worked nearly as well as his old air/air setup, but with better throttle response. (No exchanger is 100% efficient, using two instead of one means you get slightly warmer charge temps with water)

Air in/air out is the same problem that exists on every other street car turned race car (with few exceptions) and water/air or air/air heat exchangers don't change that in the least.

Water's high specific heat only means it takes a lot of heat to make the water get warmer. That's why water/air intercoolers can be smaller. You can pull the same amount of heat out of the charge air with a smaller mass of water. But you have to remember that the high specific heat of water also works against you when you're trying to shed that heat to ambient air. This is where the designers of air/water charge cooling systems always fuck it up.

And water conducting heat more easily means you could get away with less surface area to reject the same amount of heat.

That's the same mistake that so many people make with these systems. You can't use a small surface area to reject the heat from the charge air. You can't let the water get warm enough to transfer heat effectively through a small radiator, that's why these systems always heat soak. A larger and thinner radiator that didn't have end tanks blocking airflow through the engine coolant radiator is the way I would design it myself, if I were designing one.

You have to remove the same amount of heat at the front of the car as you're removing with an air/air setup. (very slightly more, actually, because the fluid pump adds heat to the water) If you design it right you could have as much or more airflow through your radiator than an air/air setup because the air/air end tanks block airflow.

Water weighs a little over 8 lbs per gallon and the final charge air temps will always be slightly higher than an air/air setup. These are the only downsides to a properly designed air/water setup vs air/air. Heat soak is only an issue when the system isn't designed well enough for track use. You have to decide whether you want to deal with more weight and a few degrees warmer air or imperfect throttle response. That's the choice.

[xwd]

I was going to add that yes the system needs to be designed for the amount of heat it needs to deal with and if it's too small, then it will heat soak.

There are some modern high horsepower cars using AWIC setups, including the Ford GT, GT500, Camaro ZL1, and the Corvette ZR1. It's not like those cars don't see track time. In the case of the Camaro and Corvette they have large front heat exchangers, Mustang is wide but not very tall. They all use reservoirs, albeit not really that large.

Drag racing obviously people use them with ice to drop the temps below ambient, something you'll never get with a air/air system.

I have been toying with using a GT500 heat exchanger with the TRD S/C. It's wide but not that tall, and about the same depth as most of the turbo air/air ICs (4"). There are also aftermarket single and dual-pass ones from C&R, Fluidyne, etc. with fans and integrated oil coolers. Either that or I could run two small PWR ones, one for each IC, but then the plumbing and whatnot gets a little more complicated.

[SprintexUSA]

Just to say it, we do not intend to ever sell our manifold separately. You're on your own.

However---give this a shot

(.160" fin height)(.6)(Laminova core")(2)(# of tubes) = Area"^2 That's the formula for the CFM flow area per Laminova stick.

http://www.frozenboost.com/ Is a spot where you can source pre-built Laminova assemblies and parts.

[CSG Mike]

Originally Posted by dwx

I was going to add that yes the system needs to be designed for the amount of heat it needs to deal with and if it's too small, then it will heat soak.

There are some modern high horsepower cars using AWIC setups, including the Ford GT, GT500, Camaro ZL1, and the Corvette ZR1. It's not like those cars don't see track time. In the case of the Camaro and Corvette they have large front heat exchangers, Mustang is wide but not very tall. They all use reservoirs, albeit not really that large.

Drag racing obviously people use them with ice to drop the temps below ambient, something you'll never get with a air/air system.

I have been toying with using a GT500 heat exchanger with the TRD S/C. It's wide but not that tall, and about the same depth as most of the turbo air/air ICs (4"). There are also aftermarket single and dual-pass ones from C&R, Fluidyne, etc. with fans and integrated oil coolers. Either that or I could run two small PWR ones, one for each IC, but then the plumbing and whatnot gets a little more complicated.

Those stock cars still overheat, and rather quickly.

[Ubersuber]

Air to air intercoolers work well for turbos since there's a bit of lag anyway. They are light and cheap and reliable. Put a big enough one in front of the radiator and charge temperatures go way down. They are also easy to fit with water/methanol cooling.

Water to air intercoolers are more efficient so can be much smaller.

The one designed by Sprintex for their kit marketed by Innovate in North America looks sized for transient efficiency. The whole purpose of the street version of the Sprintex kit is for good torque boost for very short periods. The intercooler design supplements and enhances that basic design intention. For track work or the Autobahn I doubt very much if the heat rejection capability would be sufficient. There's no room for a bigger interooler core (it would have to be deeper) so assuming the water to air cooler in front of the radiator is optimized already I see no potential for use in a turbo set up. Indeed, unless you expect sustained acceleration demands the intercooler is rightly considered an option because it will only show noticable gains when heat soak starts to raise air intake temperatures significantly.

Basically, turbos exploit heat and that heat is utilized and largely rejected right at the turbo so air to air intercoolers make a lot of sense, moving the heated compressed air right out of the engine compartment. Superchargers only heat the air by pumping it, not a lot of this heat is rejected in the engine compartment which favours the water air intercooler design. All the energy required to pump the air comes from the crank. Just BTW, Sprintex uses displacement type twin screw or lobe supercharging which does not compress the air inside the actual supercharger accounting for the measured efficiency rating, compare a turbo to a twin lobe supercharger for power output and there's no comparison.

Superchargers are intended mainly to improve mid range torque in modern applications, and have superior throttle response to turbos. For big torque and big power the turbo remains king of the hill...but off the line or mid range to pass I still prefer the supercharger.

[xwd]

Originally Posted by Ubersuber

Air to air intercoolers work well for turbos since there's a bit of lag anyway. They are light and cheap and reliable. Put a big enough one in front of the radiator and charge temperatures go way down. They are also easy to fit with water/methanol cooling.

Water to air intercoolers are more efficient so can be much smaller.

The one designed by Sprintex for their kit marketed by Innovate in North America looks sized for transient efficiency. The whole purpose of the street version of the Sprintex kit is for good torque boost for very short periods. The intercooler design supplements and enhances that basic design intention. For track work or the Autobahn I doubt very much if the heat rejection capability would be sufficient. There's no room for a bigger interooler core (it would have to be deeper) so assuming the water to air cooler in front of the radiator is optimized already I see no potential for use in a turbo set up. Indeed, unless you expect sustained acceleration demands the intercooler is rightly considered an option because it will only show noticable gains when heat soak starts to raise air intake temperatures significantly.

Basically, turbos exploit heat and that heat is utilized and largely rejected right at the turbo so air to air intercoolers make a lot of sense, moving the heated compressed air right out of the engine compartment. Superchargers only heat the air by pumping it, not a lot of this heat is rejected in the engine compartment which favours the water air intercooler design. All the energy required to pump the air comes from the crank. Just BTW, Sprintex uses displacement type twin screw or lobe supercharging which does not compress the air inside the actual supercharger accounting for the measured efficiency rating, compare a turbo to a twin lobe supercharger for power output and there's no comparison.

Superchargers are intended mainly to improve mid range torque in modern applications, and have superior throttle response to turbos. For big torque and big power the turbo remains king of the hill...but off the line or mid range to pass I still prefer the supercharger.

People use W2A usually for packaging reasons since the IC core doesn't need to be as large and can easily be integrated into other elements like the intake manifold. Or they use it for specific purposes like drag racing where they can get the intake temp below what an A2A system could get. It's popular with superchargers because the superchargers are also integrated into the manifold, unlike a turbo. As for the mid range vs. top end it really depends on the engine and the size of the supercharger. They have efficiency ranges just like a turbo does. Turbos are always going to make more power of course, they have a much larger operating range and can run a lot more boost than a supercharger without the parasitic loss.

Sprintex are twin-screw and absolutely compress the air within the supercharger housing, so I'm not sure what you are saying. The heat is generated by the compression within the housing, similar to a turbo. Roots superchargers generate more heat because they are basically shoving air into the manifold, not compressing it. It's the turbulence and compression at that point creating more heat.

[Ubersuber]

OK, then not a positive displacement type which is then less efficient. High efficiency mechanical superchargers of the twin lobe type do not compress internally.

If the air is compressed within the supercharger then intercooling is more beneficial.

I remain of the view that the Sprintex intercooler is only effective for short term boost events.

[350matt]

Originally Posted by Ubersuber

I remain of the view that the Sprintex intercooler is only effective for short term boost events.

I'd agree with that , I think a lot a people see IAT's of about 60 degrees C / 140 degF with this setup even when the ambient temps are not that high