I agree with the above posts. My centre vent just pours out the heat.

The back two vent on the hot wheels hood are useless as they are over the brake a battery box so I covered mine with lexan. The front 4 helped my oil temps greatly, it used to climb fast any time I stopped but it's very slow now and as soon as I start moving it starts dropping. They haven't been tested side by side so no one knows what hood works best on our cars but I promise you it's not a show piece, if it was I would have already replaced it!

The jpr hood comes with drip pans installed under the side vents, basically cuttting off air flow thru anywhere except the centre vent. I opened mine for better venting at stops and idle. Racers might want to keep them covered for maximum extraction from the centre vent.

Good post but I would also consider that different style vents will have individual perks at different levels of airflow/speed. Whether the consumer matches the airflow modifications to their application or not, or even has the information to do so... probably not in most cases. But we can at least be fairly certain there is another dimension to it.

Example, I am personally guessing that the vents of larger surface area, regardless of consideration to placement, should allow more heat to escape in applications such as idle, auto-x, and other "low speed" environments where there is not enough airflow to achieve a venturi effect or buildup of air pressure at the cowl. What speed these events occur, I have no idea. But I would say that there is probably a changeover that occurs somewhere on the speed axis where the style and placement of the vents needs to begin shifting to avoid areas of high pressure, or other concerns that I am unaware of.

Lol but you just proved my point. It is a show piece. You've already blocked off the back two going from a show piece to a more function piece. And it doesn't matter where the vents are in stopped traffic. Any vent on the hood will keep temps from climbing to fast since there's no movement of air when stopped, heat WILL pour out as hot air rises. The important thing is when moving does it work? With the back two blocked off I say yes.

Ok so I guess the lower temp are in my imagination? I'm not saying they didn't add the third one for looks but my car runs cool in south Florida summer and that's a fact not opinion. If large vents don't work why did it bring the temps down? I ran the car at Sebring a few weeks ago where temps were in the high 90s and 85% humidity and when pulling in the pits you can see the heat coming out the vents like a hot asphalt road. While heat rises the size of the vent still controls the volume that can get out.

http://img.tapatalk.com/d/14/07/16/a8adu3eh.jpg

This is the other side.


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A center vent would have done nothing for my car because the the intake pipe for the Stillen supercharger would block it from flowing any air.

Not sure why you had to say this. I just said "I say yes." When moving I say yes with the back two blocked off it will work. It's not your imagination since I'm agreeing with you but only since you've modded the hood will I agree.

That is a reasonable observation.

Yep. The base of the windshield is a high pressure area. That's how cowl induction hoods get their air for the intake. If the vents are at the very rear of the hood. Don't think they would be good at moving air.