DIY - Free cooling system upgrade

[Jackal]

I had done the same thing within days of owning my car, but did not take off as much of the sheet metal and I actually wrapping the edges with foil tape so it looks factory and I don't ever having to worry about cutting my self. and yes the car loves the fact cool air now comes in hit the firewall and is forced between it and the heat sheilds this keeping the turbo cooler.

[Blaze]

Originally Posted by TheBlackBeast

For the NACA Styled ducting vent, there is a lovely metal plate blocking most of the air flow from getting into the engine bay to help cool down that wonderful turbo. I have yet to decide if I want to completely remove the metal plate or modify it with some tin snips. I'll post back when I get around to this part.

I'm not a physicist and I mean no insult, but I do find it somewhat amusing when the average back yard mechanic presumes to improve upon what Mitsubishi engineers with cad designs, wind tunnel testing and degrees have determined to be the most efficient designs for the car.

I say this because the vent over the turbo is specifically designed to focus and direct the air to where the most heat is. The smaller port is there to focus and increase the air pressure at speeds and focuses the inbound air. Opening it up or removing it the panel is like switching from a laser beam to a flood lamp (if that makes sense). The air is going to go everywhere.

So, the center vent is designed to draw air in, but the forward two vents have low pressure areas on top of them and are designed to pull air out. You can do a tuft test to see how this works. The fact that one vent is capped leads me to suspect that it's there for cosmetics only. Opening it up might upset what has been determined to be most efficient for evacuating heat from the engine bay (using one vent).

[TheBlackBeast]

No insult taken. I usually come up with the same argument when people talk about removing their rear wing and adding VG's with no wing. I see your point about this possibly being tested, but how would they test for air flow inside the engine bay and directing flow to a certain area? I understand how they do this in a wind tunnel with air flow and testing for VG's & rear wings. To do what you are suggesting would require a full Computational Fluid Dynamics simulation to be run (a department in the company I work for actually sells software capable of doing this). Seeing that this car isn't built by Mitsubishi from the ground up to run in a racing event, I find it hard to believe that they would go to that length for analyzing air flow in the engine bay. I could very well be wrong on that too, but as long as we are bench racing air flow dynamics in an engine bay, why not?

[MTZL]

Its still hear say.
Whats funny is,
the wind will most likely skip over the Middle vent in the tunnel test anyhow.
Everything is a double edge sword.
If you can live with the downside of things, go for it!
Thats how I buy into thing,
if/when the bad things about the mod doesnt bother me or that I can live wit it.

[Mondo]

I love this post!

[Jackal]

The Best part is if you drive your car all year long and live in one of the most extreme climates on the planet like I do up to +35 Deg Celcius plus humidex in summer and -38 plus windchill sometimes = -57 deg Celcius. You can take out the vent plates and open up the scoop for summer then put the plates and custom cap in for the winter.

[Ralli]

Odds are pretty good the restrictors are there for rain, and rain only. I say this because Ive been into Trans Ams all my life and on my last, a '98 with Ram Air, the factory completely (or almost completely I should say) blocked off the "Ram Air" so water could'nt get into the engine (this was verified by talking to one of the engineers who participated on our board), he said though water could realistically never make the two "L" shaped bends, then get past the filter the fun killers made them close them off anyway. This is more then likely the same case here. Removing the restrictors on those cars was good for 15-20 hp on the dyno, it would be interesting if it did anything for these cars on the dyno, or if it just help cooling. My car runs cool enough, but I can never have enough power.

[Ralliart23]

my RA came with one of the vents already open, and one of them blocked off.

[TrailBrake]

I've run for several months now with the vent plates gone and fog lights removed. The car consistently runs cooler.

For car washes, I use pieces of cardboard under the vents to keep things dry. The key thing being to take them out afterwards

[BravoZero]

Originally Posted by TrailBrake

I've run for several months now with the vent plates gone and fog lights removed. The car consistently runs cooler.

For car washes, I use pieces of cardboard under the vents to keep things dry. They key thing being to take them out afterwards

Not a bad idea. I'm all for making things cooler under the hood, but that was one of my worries.