Seal the bottom of the engine compartment?

[mustangdave]

Has anybody ever blocked off the bottom of the engine compartment to keep dirt and mud off of the engine? I did this partially on a car one time and it really kept the engine clean. I wonder if it could be completely blocked off without overheating? I'm sure the engine would stay cool enough with a good cooling system, but then I think about the heat from the headers?

 

[HistoricMustang]

I think the result might be high heat and fumes inside the car.

Interesting concept.

HistoricMustang
www.historicmustang.com

 

[mustangdave]

I hadn't thought about the fumes. There would probably need to be an opening or pipe at the back of the engine compartment on each side to vent fumes and header heat. I know some cars have the rubber like material at the bottom of the radiator attached with dzus fasteners. I assume this is a rock guard for the front and bottom of the engine; I was just wondering about carrying that a step farther; ( hey, at least it's something new to talk about).

 

[MustangMatt1966]

yeah it is something new to talk about and its interseting too, it would be pretty sweet, i wonder what it would look like in chrome....

 

[HistoricMustang]

My hood is actually raised about 1/2 inch in the rear to let our air build up in the engine bay while at speed. Perhaps this concept would take out the bad heat and fumes?

HistoricMustang
www.historicmustang.com

 

[2nd Mustang]

My hood is actually raised about 1/2 inch in the rear to let our air build up in the engine bay while at speed. Perhaps this concept would take out the bad heat and fumes?

We used to do this at the drag strip, poor man's cowl induction, being that the base of the windshield is a high pressure area, so it was said. Hmm, gives me an idea for a new thread...........

 

[bnickel]

you could use some 68 gt500kr or 280z style hood vents, that's is truly their only purpose, to vent hot air from under the hood, the closer you can get them to the windsheild the better, because of that previously mentioned low pressure area at the base of the windshield, it will help scavenge or suck the hot air out

 

[HistoricMustang]

On the early models there is a large distance between the edge of the hood and the windshield so the air can actually get out. With late models it gets tougher as the low pressure area gets larger.

I actually tested this theory at Daytona using the tape you see being used at NASCAR. With our stuff the tape is happy!

HistoricMustang
www.historicmustang.com

 

[68_stanger]

That is a interesting concept. What about some kind of louvers cut into the cover on the underside, to let some of the heat/fumes out?... None the less its something to think about.

 

[HistoricMustang]

Louvers are good. I think they can actually be used on the fenders as well to let the air that builds up in the wheel well area out.

HistoricMustang
www.historicmustang.com

 

[68_stanger]

This thread makes me want to go take a closer look at the under side of my stang

 

[Loup-garou]

Check the Shelby Cobra Daytona Coupe hood design. That race car ran a full belly pan and exhausted all of the cooling system air through the top of the engine compartment, right through a sheet metal duct that sealed to the hood.

You *have* to exhaust the air somehow, or the radiator loses effectiveness.

 

[Paul619]

Are you mud bogin that thing is that the problem? I actually think the louvers facing toward the rear of the car would work. The air that flow in from the radiator would get pulled through them I think. The heat from the exhaust may be too much and then where are you going to get cold air from? Actually on second thought I dont think it is a good idea. you may reduce the airflow too much and not have enough through your radiator. hmmm i am going to have to think about this more.... need to think back to my aerodynamics class

 

[DukeGnarley]

wouldn't some sort of upside down bug shield at the front of the engine compartment be sufficient to keep most of the dirt off of the engine? it would also leave plenty enough room for the hot air to escape. just a thought.

 

[302 coupe]

I don't get any mud or dirt on my engine....and I live down a long dirt road. If you have a belt driven fan sometimes they will kick up a lot of dirt, you can put a shroud around it and that will help alot. I think if the bottom of the car were blocked off you would have some serious underhood airflow problems. It would be a lot simpler to avoid flying through the mud puddles.

 

[351carlo]

Think about this as an answer....

Instead of using solid sheet metal to block off the dirt, use a soffit type metal layout. The vents would open towards the back of the car, allowing the air to vent air. Due to the direction of their opening, the dirt wouldn't be allowed in.

Just a thought.

 

[Route666]

I think you'd have to leave room around the exhaust because of engine movement, heat, fumes, and airflow for the radiator. While my car doesn't have it now, in the Haynes manual I have, it was an option to have a shield under the front of the engine bay, where the sway bar is. It is louvred. I think it would help air go through the radiator instead of up from underneath as well, and direct the air over the engine before exiting.

 

[mustangdave]

Glad to see so many ideas. I'm not mud-bogging: I just thought it would be a great leak detection/dirt prevention idea. I also wonder if there would be any aero benefit from keeping the turbulent air in the engine compartment from slamming around by directing under or out the sides of the car. I know this would be next to nothing at highway speeds, but in theory?

 

[Route666]

Yes I've been thinking about this idea, I started around the same time I posted the thread on having a shroud around the radiator to vent air to the wheel wells.

I think it would:

1. Help cooling by splitting the under-car airflow from the radiator airflow, and by directing air over more of the engine (maybe).

2. Help aero slightly, maybe a little more stability.

I'd say the cooling would be the greater benefit of the two, and even then maybe not much. Keeping dirt and water off your belts, p/s pump, altenator, etc might be the most benefit you'll see from it.