Ok, Who wants to do some thinking?

I have been doing some light technical reading lately and came up with some conclusions.

The current crop of Intercoolers is good, but there appears to be an easy way to make another leap in efficiency and power production.

The common thought seams to be:
1) Make an intercooler with the largest cooling area as possible.
ie. Bigger is Better
2) Make the piping straighter and have less bends
3) Make the End-Tanks flow to the entire core
ie. Smooth flowing triangular shaped
Some do these better than the others, but let's forget about that.

**All of these intercoolers use endtanks on the horizontal ends**
ie. <ICPipe> [ENDTANK] -C O R E- [ENDTANK] <ICPipe>

BUT... According to Corky Bell (And some other sources)
You can have the same frontal area, but increase the efficiency of the intercooler with endtanks mounted on the top and bottom.
The path for the air to travel through is shorter, and subsequently you get less pressure loss. The more tubes the air goes through, the better. Period.

An example (I saw this yesterday, and got the PERFECT example)
LOOK at the endtanks, smooth efficient, BUT MOST IMPORTANTLY, it gets airflow to ALOT more tubes. Less pressure drop, same frontal size, greater efficiency.



So, I'm calling out to the tuners!
Who wants to R&D something like this?
Big core, top and bottom endtanks with proper design (Read Maximum Boost), and do some shorter and straighter piping.


JD
jdg228*nospam*@psu.edu

 

From Maximum Boost by Corky Bell
Available at Amazon.com

"When adequate space exists for a large IC, the decision must must be made about the direction in which to orient the core. Unless overwhelming reasons dictate otherwise, the core should always be constructed to provide the greatest possible internal flow area. The direction of flow is unimportant. For example, the ICs in figure 5-15 take up the same space, but the vertical top-flow unit has more internal area and, hence, considerably less restriction."

 

If you are looking for maximum eficiency, why don't you look into an air/water solution?

 

With top to bottom you have less restriction to flow, but you also have less "stay time". The air can end up flowing through the core so fast that it doesn't have very long exposure to the cooling effect from the cross flow of fresh air flowing though the intercooler.

Keith

PS: I have a top to bottom flow sperco FMIC if you want to buy it Used it on my Galant VR-4 to good effect.

 

i agree with fourdoor.

more tubes, but each is shorter.



An anecdotal argument for Air/Water:

my old 5.0 had a Vortech Aftercooled S-trim pushing 13 psi, which is quite a bit of boost for a 10 lb kit (no pulley changes) blowing through a heat exchanger.

the kit worked great. the inlet (near the blower) would be super hot, while the outlet was cooler than the intake manifold that it met up with.

Then I went to the strip to see how much difference it would make to add super cold liquid.

I first tried dry ice and a 90/10 split of antifreeze to water. the antifreeze just got globby and wouldn't flow and the water made ice amidst the 'freeze. trippy lookin' with the fog pouring out of the engine compartment.

drained the coolant and filled the water tank with ice, then water to fill it in. ramped the timing to 30 degrees total on the laptop and that netted a 12.5 @122 on regular radials w/3600 lbs raceweight. oh yeah, and a couple of gallons of 116 leaded to spike the half-tank of 91

 

There's basically no difference in going the long way through the core, or the short way. Assuming a given volume of air, the total cooling time is going to be the same. If the core is long and skinny, the air will go through fast (but there's more air in each tube). If it's short and wide, it'll go through slow (but there's less air in each tube). Assuming the same core size and shape, the total time of a given volume of air through the core will be the same regardless of flow direction.

Up to a point, a larger core area is better for dissipating heat, and I think that's what Corky was getting at. If the end tanks are taking up available area that could be used for a larger core, by all means put the end tanks in a spot that won't reduce the core size.

But there comes a point where you've cooled the intake air to ambient temperature, and you're not going to have any improvements with a larger core.

Who's got some data on before- and after-intercooler air temperatures on the Evo?

--Dan
Mach V
MachEVO.com

 

Air-to-water intercoolers are an interesting method, but they have their pros and cons.

Pro:
- You can load up with super-cooled liquid for a short burst of really cold intake air
- Water has a HUGE capacity for absorbing heat
- The air-to-water core is very small and compact

Con:
- Once the intercooler water heats up, it can take a LONG time to cool down. In the mean time, you've got an interheater!
- Building a whole new coolant circuit in a car is expensive, heavy, and an additional maintenance chore
- You lose efficiency by transferring heat from air to water to air

For a pure drag race car, there's no question, you can't do better than a tank full of ice water for an intercooler. For street cars, it's not practical to load up with ice all the time.

The water circuit behaves differently than an air-to-air intercooler with regard to transient heat spikes. A water system will be relatively insensitive to a short burst of hot air -- the thermal mass of the air is pretty small compared to the thermal mass of the water. (I'm sure I'm not using the right technical terms here.)

So for quick bursts of power, the water-to-air system will be good at keeping the intake temps cool.

For longer-term high-throttle use, though, the water circuit will eventually heat up, and it will take an equally long time to cool back down. If you were doing road racing (with perhaps 40% of the total time at full throttle), a water system probably wouldn't cut it, unless your water radiator were as big as the whole front of the car. Even then it might not be big enough, because of the efficiency loss at each stage.

Some cars that have air-to-water intercoolers from the factory include the Syclone/Typhoon turbo trucks, the newer SVT Lightning truck, and at least one older model of Subaru Legacy turbo.

--Dan
Mach V
MachEVO.com

 

I also heard Ford was in the process of patenting an intercooler cooler using bursts of super cold refrigerant from the air conditioning system. Ford engineers acknowledged that the intercooler would only be effective for about 10 to 12 seconds. Then they noted that the 1/4 mile is usually over with not much after that amount of time.