DIY - Free cooling system upgrade

[TheBlackBeast]

For those looking to keep their RA a little cooler, there are some factory installed inhibitors that restrict airflow in/out of the engine bay. Some might argue that well, the factory must have put them there for a reason. I argue that, well, they must have originally designed the opening the sizes the way they did for a reason and then thought to cover them up with restrictive plates.

One might also argue that by removing the plates you will allow water into the engine bay. I would ask this of you first before making such a statement. Go drive your car on a rainy day and then look under the hood and tell if everything is dry or wet. Or wash your car and tell me if the engine bay is dry when you are done and first open up the hood.

However, if you are worried about voided warranties and such, then this probably isn't for you. If you are looking to give its air system some proverbial ex-lax, then check out the following areas on your car.

[TheBlackBeast]

For the first 2 vents on the hood, there are metal plates sandwiched inbetween the hood and vent. In the pics for this post, they are already removed but I've gone ahead and pointed out what needs to be done to remove them.

[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.

[TheBlackBeast]

Finally there is the fog light housings at the corners of the front bumper. I understand if you like your fog lights there. I did too until someone in front of me launched a piece of road debris and broke the glass cover on my front right fog light. The bulb amazingly still worked. However, it just didn't look right so I thought I may as well pull both of them. This will also let more air through the front of the car to cool brakes and other things. One of these days I will run a hose of some type from the hole from the fog light to the brake system.

[TheBlackBeast]

As an added bonus, Evo's have additional venting in the front air dam area but not the RA's for some reason. I did a little dreaming with photoshop to see what it would look like with the same vent holes. Not bad I think... Depending on whats behind there, I may or may not modify that piece. Another weekend project.

[Ladogaboy]

Something to consider with those vents is that the EVO, RA and all other Lancers share the same chassis, but have different body panels and other bolt-on supports. I'm wondering how many of those covered gaps wouldn't be covered in other models?

Either way, I have to imagine that more airflow into the engine bay has to be a good thing. :)

[MikeW-RRE]

The designers put the vents there because that is what is needed to keep the engine cool when you are having too much fun. Then later the VP of Foo-Foo and No Fun comes along and points out the mother-loving bed-wetting sissies will cry about water spots under the hood so they order them blocked them off.

Here in So Cal it rains 4 times a year and you can always pop your hood and dry things off after washing the care. The cool kids yank out the block off plates. I cant speak for the rest of the country that actually has "weather"

Mike W

[AVENGER]

Living in New Jersey, we get every season.. But HELL,,, Rally cars are meant to get dirty.. Nothing a little water and a towel won't fix..:rolleyes:

[MTZL]

^ OR STEAM CLEANING and pressure wash with degreaser or engine cleaning foam. Thanks for the picts BlackBeast.

[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.Well, looks like tin snips were in order for the day.

The black plastic clips were the biggest PITA. I lost one of them somewhere in the engine bay when pulling it off. Don't expect the plate to come off in perfect shape either, unless you have a special tool to pull those off. The metal clips came off easy with pliers.

I used a sharpie and eyeballed the extents of where I wanted to cut and went to town (hence the curved edge). The plate cut really easy. I took the pliers and slightly bent the edges up so there wouldn't be sharp edges protruding into the engine bay. Since I cut off part of the plate that one of the clips held it on with before, I used the left over clip for the hole that lost a plastic clip.

I'm glad everyone is enjoying the write up!

[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]

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? :D

[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]

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.

[TheBlackBeast]

I've been running this way for close to 50k miles. Car hasn't broke yet (knock on wood)...

[mitsufast]

I would say another thing to consider with this modification is the aerodynamics. The skid plate under area there makes it so air passes under the car instead of going up into the engine bay. I would say however the holes are small and probably wouldn't make enough of a difference to effect MPG.

[Esco]

Ill try this when I get home, cuz I do notice the car runs pretty hot! Sometimes I can smell it when I get out

[Esco]

My question now is, if everybody's car runs cooler after doing this from all the air getting in, would you consider a SRI intake now?

[BravoZero]

My question now is, if everybody's car runs cooler after doing this from all the air getting in, would you consider a SRI intake now?

Negative, opening those vents is going to give you slightly cooler temps but not enough to really make a huge difference. It will still get hot as balls under the hood.

[Esco]

Negative, opening those vents is going to give you slightly cooler temps but not enough to really make a huge difference. It will still get hot as balls under the hood.

Aight thanks! This is why I like this forum, y'all are really helpful

[BravoZero]

Aight thanks! This is why I like this forum, y'all are really helpful

No worries, that's what we're here for! :D

[Mkid]

Has anyone actually proven this yet in any reliable manner? I still question if it is like this by design to allow for a specific flow of air.

[zeRep85]

The designers put the vents there because that is what is needed to keep the engine cool when you are having too much fun. Then later the VP of Foo-Foo and No Fun comes along and points out the mother-loving bed-wetting sissies will cry about water spots under the hood so they order them blocked them off.

Here in So Cal it rains 4 times a year and you can always pop your hood and dry things off after washing the care. The cool kids yank out the block off plates. I cant speak for the rest of the country that actually has "weather"

Mike W

Mkid, Mike explained it perfectly! ha

Also, lets say you switch to a ebay body kit or any other body kit/front bumper...most these body kits dont have these restrictors, some even have MOARRRR vents...i.e. fq400 kit w/ the intake opening.

[BravoZero]

Can the pictures on the first page be restored? I think they were lost when the site crashed.

[TrailBrake]

Worst-case, I'll take pictures in the fall when I put the vent shields back in.