Air-to-Water Intercoolers?
 

Has anyone attempted to run an air-to-water intercooler setup on the 993 instead of the air-to-air setup?

Just wondering if this setup would perform better or not.

I think TTP (www.t-t-p.de) did an air/water set up on the turbo kits he did for the N/A engines in order to maintain the standard folding rear spoiler....
9ff used one for the 38Xkph record car - I asked him about its efficiency at the Essen Motorshow a couple of years ago and he didn't really want to enter into a discussion on the merits/downsides of this system.

The Merc 55 Kompressor engines run air/water and in discussions I have had with Wolfgang Vath (www.vaeth.com) they can lose quite a lot of power through heat when they get warm, so much so that he invented a special fuel cooling system which utilises the a/c in an attempt to maintain hp when hot.

Suffice to say all the air cooled racers ran air/air systems. The layout and positioning of the engine makes the big air/airs the best option with the low pressure zone combined with the cooling fan drawing in massive amounts of cooling air once at speed....

Turbokraft builds a real monsters, also these watercooled versions.
See http://turbokraft.com/gallery/Mike

I spent a lot of time on this issue back when making my car. I decided to stay w/the air/air due to:

1. None of the companies doing air/water could give me any facts/temps on effeciency
2. Weight
3. Ruf used it for a very short time and ditched it
4. Porsche used it in racing application and ditched it
5. Air is free and easy to find
6. No one really had their act together to convince me it was a viable option...

I continue to wait to see if anyone comes out w/anything smart on this as I would still like to go air/water if it was a good design, etc.

Keep us informed if you hear of anything that looks cool. I even contacted Turbo Craft in Az re: the 993 they converted to air/water...they could only say they had "tubes" for certain hp applications, which again, didn't make a compelling case to install. They did a very nice job on the car that was featured in Excellence Magazine, you may want to look at that.

I feel guilty that I have water in the windshield washer.

Thanks for all the feedback and input guys!

My other car is a 2003 E55 and it has a few mods.. I have been battling heat soak with the air/water setup but that is because of the poor location the factory chose to install the heat exchanger (sandwiched between supercharger and engine block)..

I thought if a good efficiency air-water system could be put into the 993 it would make the whole setup more efficient (less boost loss)... was experimenting with Barrel intercoolers and water injection...

I might explore some of these ideas on the 993 once I start taking my car apart.. Just wanted to get an idea if anyone else has gone into this yet.

TB mentioned cooling the fuel, which porsche did in the 928S through the air conditioning system. Anybody try that on the 993tt. I've been thinking about it for a year, and there are a number of military hardware parts that are used in jets for this reason. Any backyard engineers try that yet?

If you want to cool your fuel you can grab all the hardware off the 996TT..

Some development is being gained with using A/C to cool your charge air!! Now thats something that I would look into..

My E55 mercedes is rigged with a Fuel cooler that uses the air conditioning system.

I am trying to bring alot of the concepts and ideas I used on my E55 over to the Porsche and see what will come of it. :)

Cooling is the first thing I go after with performance vehicles so I will be trying them on the 993TT soon. Fuel cooler, different intercooler setups, and water injection are the starting points.

I've already found a starting point for the intercooler setup..

This is the intercooler I am going to try first... Testing has shown +1psi increase in boost at the throttlebody over stock setup. :)

The first pic shows it stuffed into the tail of a 993TT without the lid installed.. The second pic gives you a nice visual of the diffference in size between stock and this one that I will be installing.

http://69.17.158.20/vrus/993tt/993intercooler.jpg
http://69.17.158.20/vrus/993tt/993in...er_Compare.jpg

The problem with cooling the airstream w/ A/C is that it ends up being very restrictive.. I dont think they are going to be able to create something that works properly and still flows enough CFM of air to the TB. But.. Hopefully I'll be proven wrong.

Who is working on this by the way?

Bigger isn't always better.. If the air doesn't cover/hit all of the core it will actually start to soak heat from the engine bay.. Not good... The pressure drop isn't as important as the ability to remove the charge air heat.

Last year when I was talking w/ Todd at Protomotive he mentioned this and sounded interested in it. While it's a cool idea I get the feeling when you crunch the numbers any benefit will be small vs going w/ the secan.

Cooling the fuel would be a BIG improvement in the performance department. The use of the air conditioning to do so is counter productive as it would have to be running to cool the fuel, something that's not helpful during track use or 60-130mph.
I've done water injection in another project (944 turbo) and it has reliability issues. I'm looking at military applications that would drop the fuel temp to around 30 deg F. On a 95 degree day we've seen fuel temps over 120 deg f. which causes huge performance drops due to high temps. I believe (without any scientific evidence) that droping the fuel temp would more than make up the intercooler inefficiencies. Any jet mechanics out there that can comment?

Yes.. Good point. I did think of that also. I will place a few thermocouplers in the engine bay and take some temp readings while driving.

If heat soak becomes a problem, a thermal break can be placed between the intercooler & the engine to keep radiant heat away from it.

I also have access to a patented process which coats heat exchangers and provides a 25 - 30% increase in heat dissipation efficiency. Its not cheap to do, but it works. It is used in the aerospace industry and now being used in the automotive sector. Alot of endurance race teams coat their rads & heat exchangers with this stuff.

I've used this on my E55 and it does help. IAT measurements did go down after my heat exchanger was coated.

Do you have a pic of this Secan cooler??

The unit I run on the E55 is hooked up to the low pressure side of the A/C. It works even if the A/C is off.. I just assume its because the system is pressurized and freon is flowing regardless of whether the A/C is turned on or not..