Author Topic: Another hood vent idea  (Read 554 times)

MiniVanMan

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Another hood vent idea
« on: May 03, 2012, 11:22:07 AM »
The guys on the Cherokee forums keep stressing how great hood vents are to allow hot air to escape the engine bay. If you own a Cherokee, you know just how fucking ridiculously hot it gets in there. It's just poor ventilation design. I know most of the engine is cooled internally, but I don't believe that the residual heat trapped in the engine bay isn't bothering anything, and I'd like a way to vent it out.

BUT, I don't like the idea of there being a gaping hole in my hood. Some of those guys said not to worry about rain getting in there, just use dielectric grease. That's not good enough for me.. I don't trust that advice.

So I was trying to think of a way to make a hood vent that you could cover easily when it started to rain.

Then it hit me.



Aside from fabricating and mounting the flap, I can't imagine it being too hard to use some carburetor hardware and run a choke knob into the cab which can be used to open and close the flap at any time.

Anyone have any bright ideas on how I can make this idea work?

I'd be buying a spare hood to cut apart rather than cutting into my own hood, of course.

Southern_Pride

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Re: Another hood vent idea
« Reply #1 on: May 03, 2012, 08:25:12 PM »
I can tell you firsthand, a cowl hood on my car didn't do shit to remove heat. Ram air works awesome though. And it doesn't take much of a scoop.

87Warrior

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Re: Another hood vent idea
« Reply #2 on: May 04, 2012, 06:30:45 PM »
I would kill to get a cowl hood for my 92. The problem is they are not being produced and when they were, cost an arm and a leg. A few well respected member of the comanche club swear that a cowl hood has done the most for their cooling. The XJ/MJ have such a tight engine bay that no heat can escape from under the hood.

But, back on topic, I think that 'flap' is a great idea. I will probably spend several house looking at my hood to see how it could be done.

GMCBrewski

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Re: Another hood vent idea
« Reply #3 on: May 04, 2012, 10:05:31 PM »
Don't know how the back of the hood looks, or how much space you have, but a simple hinged flap like those trash can lids you can spin around could work. Use a push/pull solenoid and walla. It would be tough to completely keep water out though. It would probably be easier to just inset some open vents, then design some easily removable sealed covers for them. Welding in big louvers would also do the job and keep rain out, but would look gaudy.

My first thought was something along the lines of this.



Disregard my mad art skillz. :lol:

Onyx Dragon

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Re: Another hood vent idea
« Reply #4 on: May 05, 2012, 01:05:45 AM »
I can tell you firsthand, a cowl hood on my car didn't do shit to remove heat. Ram air works awesome though. And it doesn't take much of a scoop.

Bad idea.  "Ram Air" is not supposed to be used to cool off the engine bay.  That will allow a lot of dirt, grit, bugs, and road grime to find their way to your engine, which will then cake on the engine, which will then cause the engine to run hotter.

Nick, I went with a 96-97 Grand Cherokee fan clutch (IIRC, that's the right year).  That does a lot to keep the engine temp down.

Southern_Pride

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Re: Another hood vent idea
« Reply #5 on: May 05, 2012, 02:56:21 PM »
Have you seen how dirt is on my car? Its not any cleaner under the hood.  And its better on the motor than rammed through the airfilter. Motor can be washed on the outside.

Turd Ferguson

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Re: Another hood vent idea
« Reply #6 on: June 06, 2014, 01:17:23 PM »
I have a 1987 Toyota 4x4 p/u with the 22rte turbo motor and with that cast iron exhaust manifold and turbo it gets real toasty under the hood,especially in the summer. I just put a side intake vent off an 80's mr2 in the hood right above the exhaust manifold. Sitting at a stop light you can see the heat waves really rolling out of there. Any rain  boils of instantly while running,and any over night rain cooks off shortly after start up. I have a spare hood I'll eventually put a cowl hood scoop on to keep the rain out.