Charge cooling. Which way is best???

moggy · Post by **moggy** » Tue Apr 03, 2001 7:49 am

OK lets have your thoughts and experience on charge cooling. Which way is best for a bug

Air to Air
Water to Air
Water injection

Who used which ones and what do you think??

Steve C · Post by **Steve C** » Tue Apr 03, 2001 8:37 am

Hi
I posted the information on another topic below.
Regards Steve C

The guys down here (Australia) that are running turbos are using programble injection and water to air intercoolers. These are street driven bugs but on the strip they will turn the boost up to 25 - 30 psi, then turn them back down for the drive home. The water to air intercooler can handle high temp spikes and still keep the intake temp down. A friend mine is running a 2007 berg motor with efi and water to air intercooler. He has a probe on his air cleaner and one near his throttle body, at 15 psi he usually runs 40 Celcius at the aircleaner in the engine bay and 50 celcius at the throttle body. It generaly runs this 10 deg variation all the time, see his car here http://www.clubvw.org.au/leigh_harris.htm.
Some suggested reading. http://www.clubvw.org.au/illawara.htm
http://www.autospeed.com/A_0084/article.html
To get the best out of a turbo bug motor you must intercool and air to water seems the way to go on a bug.

turbo6bar · Post by **turbo6bar** » Tue Apr 03, 2001 8:57 pm

Moggy, I have no experience with a turbocharged engine, so what I say next is purely from what I've read.

I think the best way to cool is to use an intercooler, or either type. But, if you can't fit one, water injection does work. Autospeed sells a nice intelligent water injection module that injects water into your pressurized air. www.autospeed.com If I get around to installing my M62 Eaton blower, I will probably do the water injection route. I have heard a 50/50 water methanol mixture is best, and the best results occur when your injection rate is roughly half of your fuel flow rate (via tests conducted by Ricardo). If you are under boost a lot, then you would need a large tank, but if you are only in the boost 5-10% of the time, as I imagine you are, then a smaller 1-2 gallon tank will last you quite some time.

Just my 5 pence.

Jay

volkaholic · Post by **volkaholic** » Wed Apr 04, 2001 8:23 pm

If you do go with a water injection system, spend the few extra $ & put a low level switch on the tank with at least a warning light on the dash so you don't run it dry. If you are depending on it & you loose or use up your water, you melt your engine. You could use a sensor from a watercooled Vanagon as they had a switch in the coolant resevior. I'm sure other cars have something similar. Air to air intercooling is by far the simplest as you have no moving parts, but it takes more room. Air to water intercooling is probably the most complicated as you need a pump, intercooler, lines, small radiator, etc to run it. I've heard of people using 12VDC boat bilge pumps, at least then you don't have any belts & pulleys to deal with.

Bobtail · Post by **Bobtail** » Wed Apr 11, 2001 4:13 pm

Is this for the street and strip?
I would suggest a charge cooler like Russ Fellows uses which is water filled for the steet and CO2 filled at the drags.