Intercooler in luggage area

[wookey]

Hi all

Thinking where i can mount intercooler. thinking behind the back seats. I have the half moon vents so was thinking of steeling this feed (one or both) to feed a enclosure. hot gas escape above the gearbox.

Has anyone done this? photos or experiences ?

Thanks

w

[petew]

There is some merit to the idea of putting an air-to-air intercooler in the luggage area behind the back seats. The Kremer Porsche K3 IMSA racer did exactly this.

With bodywork...

http://www.motorsportretro.com/wp-conte ... GTP-15.jpg
Without bodywork...



You'll need to cut that L shaped panel out (firewall/luggage floor) and flip it around. You're biggest challenge will be getting enough air into that space for the intercooler. As for the half moon vents, I suspect they don't have enough surface area to capture enough air to cool the intercooler effectively. What you're looking for is 40% of the surface area of the intercooler and an unobstructed (laminar) airflow to the intake. There are a couple of ways of doing this. None of them are super subtle.

The easiest is like the "Inch pincher" sidescoops...
]http://aws-cf.caradisiac.com/prod/mesim ... hertoo.jpg

You're other alternative NACA scoops in the windows...

http://images.thesamba.com/vw/gallery/pix/348820.jpg
http://images.thesamba.com/vw/gallery/pix/789480.jpg
I spent time with a guy who had a WRX motor in a bug and used 2" holes in the top of the rear fenders to get air to the standard subaru intercooler on top of the engine. He said, "air velocity helped" as the car sped along.

You're other big challenge will be adequately sealing the new open area in front of the motor as well as the motor so that hot air exits the engine bay UNDER the motor. Which is why, I think the easiest thing is the use a water-to-air intercooler as many of us have. Kremer went from water-to-air to air-to-air on the Porsche 930 track specials. However, they had a couple of advantages.
1. The car was doing high speeds so getting lots of cool air into the intercooler was somewhat easier and it was less prone to heatsoak accordingly.
2. The bodywork of the car was largely free to modify.
3. They didn't have to see out the back window of the car.
4. They had an unobtainium budget and a wind-tunnel

Me personally, I had the radiator for the water-air-intercooler mounted under the car next to the gearbox. I found there was LOT of heat coming off the drivetrain. While intake temps stayed low from startup, once the car stopped is suffered instant heatsoak it never really recovered from it. I put the radiator at the front of the car after that. My experience tells me, it's easier to run a few pipes to the front of the car and use a water-to-air intercooler than duct out the whole back of the car for an air-to-air intercooler.

[wookey]

Thanks for the comments and time to input.

agreed that if i simply ducted off the cresent vent and pushed it into an airbox, the very tight angles would actually stall the air or at least make it very inefficient . Speed would help "push" it through but thats not really helping the design again as you mention.

I think I am quickly comming to the same conclusion, you simply cannot offer a smooth enough airflow at volume required to cool. The only other option would be to cut scoops into the floor pan and drag it up and through but i dont like that option either.

I was really trying to stay away from water to air. It is more efficient and the sensible option, however as there currently is not a motor built, MY current thinking is " well if i am running water hoses, why not make them bigger and add a subaru engine out back. Certainly cheaper and more reliable big HP"

Thanks for the input appreciated to think through the next phase of the build. will continue to be reading T1 turbo applications

[Chip Birks]

I have a water to air setup in my car, sitting above the package tray. Works just fine. I have a fairly large water tank filling the cavity opposite the battery under my backseat. I can run 25psi and see intake temps increase 10-15°F and then come pretty much right back down to where they were previously. I have never done anything to chill the charge, always just run water at ambient temps. I have a temp sensor in my water, but haven't seen summer temps since i installed the sensor. I hope to gather lots of data this next year though. My biggest gripe with the intercooler being mounted in there is that it makes the cabin of the car very loud.

[MarioVelotta]

Here is the package tray intercooler setup I was running for a couple years. I really liked how it worked out. The plumbing could have been a little nicer but it did the job Motor was a 2276, Only pushed to 20psi a couple times, normal boost was 15-16psi.