🤔 Hood/ Bonnet Venting 🤔

PaydayGabe

Active member
So,, will most of the mechanical issues resolved, 🙏. I'm thinking about some vent openings in the bonnet.
This Generation Montero Sport (2002) has identical possibilities on either side of the hood. Not excessive but would definitely allow some Hot air escape. 20200525_232605.jpg
The area's considered are highlighted w/Red.
If opened,, they would be screen covered.
The silver magnetic dish is for,, just in case nuts and bolts.
Thoughts are appreciated,, G.
 

Mudrunner

Adventurer
I would check out the diesel hoods for Ideas. The one on those is located left hand side.

Sent from my Moto Z (2) using Tapatalk
 

mudraider

Adventurer
There has been some interesting discussions about this before, all over the Internets. Hood closed, forward motion pushes air through, hits firewall and goes past vehicle. Holes in the hood interrupts that flow, possibly taking away air flow. Otherwise, why don't they just do that from the factory. Some people go with that theory. I go with usage. I don't do a lot of highway driving with mine. Mine is more of a trail vehicle down here in Florida. Where it's already 79° at 0730hrs on it's way to a mid 90°temperature. Slow 4wd driving is the norm. Lots of idling waiting for jeeps to quit posing on rocks. But I have put on a cowl induction hood scoop that allows air to naturally rise out of the engine compartment. Seems to work great with the Volvo electric fan. That scoop on the hood, Mitsu put that there to get cool air to the intercooler, not to vent the engine compartment. Something to think about there I believe.

Sent from my SM-G950U using Tapatalk
 

dos531

Member
There has been some interesting discussions about this before, all over the Internets. Hood closed, forward motion pushes air through, hits firewall and goes past vehicle. Holes in the hood interrupts that flow, possibly taking away air flow. Otherwise, why don't they just do that from the factory. Some people go with that theory. I go with usage. I don't do a lot of highway driving with mine. Mine is more of a trail vehicle down here in Florida. Where it's already 79° at 0730hrs on it's way to a mid 90°temperature. Slow 4wd driving is the norm. Lots of idling waiting for jeeps to quit posing on rocks. But I have put on a cowl induction hood scoop that allows air to naturally rise out of the engine compartment. Seems to work great with the Volvo electric fan. That scoop on the hood, Mitsu put that there to get cool air to the intercooler, not to vent the engine compartment. Something to think about there I believe.

Sent from my SM-G950U using Tapatalk
This is actually a common misconception. The hood area for the most part is a low pressure area. That means at speed the air will flow from the high pressure area of the engine compartment outwards. Towards the rear of the hood it becomes a high pressure area when the air hits the windscreen, so its best to keep the hood vents to the front half of the hood for maximum effectiveness at speed. As you said at low speeds none of that really matters and any holes will help hot air escape the engine bay.

You definitely don't want to add any sort of scoop if there is no intercooler to feed air to. All the air entering the engine bay should pass through the radiator.
 

RyanY

Adventurer
This ^^^. Look at how hood vents are designed and where they are located on factory vehicles, the ones where manufacturers spend millions of dollars on research and design. They are always towards the front of the hood, usually right behind the radiator so they function as a means of extracting the hot air that's just passed through all the heat exchangers in the nose of the vehicle. Vents towards the rear of the hood can allow the high pressure air that stacks up at the base of the windshield to flow into the engine bay, raising it's pressure and actually reducing the airflow coming in through the front of the car.
 

Mudrunner

Adventurer
An alternative to holes would be a second electric fan. I have seen that done I think here in this forum by a few different people.

Sent from my Moto Z (2) using Tapatalk
 

RyanY

Adventurer
An alternative to holes would be a second electric fan. I have seen that done I think here in this forum by a few different people.
Really, if your cooling system is properly maintained and functioning as it was designed, there should be no need for hood vents or extra fans unless you're doing slow rock-crawling in high temperatures.
 

PaydayGabe

Active member
Thanks again for all the replies 🙋‍♂️.
It was a thought initially,, as of September last year, the vehicle has had a complete top end timing service including the cooling system. Everything except the fan clutch, which will be upgraded this weekend.
That said,, I am shooting for reliable/ efficient cooling. The desert SW is unforgiving in the summertime. Today we expect 107° in my area ( Clark County Nv.).
 

Forum statistics

Threads
178,368
Messages
2,782,504
Members
213,218
Latest member
smith123john
Top