Do vented hoods actually work?

[dawagarage]

Originally Posted by Def

You're wrong. The base of the windshield is a high pressure area at speed. It will force MORE air into the high pressure underhood area.

this is what ive heard from a lot of ppl that track their cars. however ive also heard (& speak from experience) that @ a stop, ie traffic light & 'pit stop areas'.... vented/raised hoods do help to allow hot air to escape from under the hood.

[Def]

Originally Posted by hotboiblaze

this is what ive heard from a lot of ppl that track their cars. however ive also heard (& speak from experience) that @ a stop, ie traffic light & 'pit stop areas'.... vented/raised hoods do help to allow hot air to escape from under the hood.

Just one question... how would an aerodynamic high pressure zone form at the base of your windshield when the car is NOT moving?


So yea, I guess it "vents heat" when you're stopped, but when do you want more cooling when your car is stopped and less when it's moving? Engine running hot as you're creeping to the local hard parking spot?

[dawagarage]

Originally Posted by Def

Just one question... how would an aerodynamic high pressure zone form at the base of your windshield when the car is NOT moving?


So yea, I guess it "vents heat" when you're stopped, but when do you want more cooling when your car is stopped and less when it's moving? Engine running hot as you're creeping to the local hard parking spot?

'when do you want more cooling when your car is stopped' = in the shitty bumper to bumper traffic that LA and san diego provide us with, especially on hot days. im speaking in regards to a dd, non tracked car. on the highways/not in traffic/etc, the inrush of air through the radiator negates the 'base of the windshield' problem.

[S14DB]

Originally Posted by hotboiblaze

on the highways/not in traffic/etc, the inrush of air through the radiator negates the 'base of the windshield' problem.

No, it won't. The pressure in the cowl area is greater then the air in front of the radiator. The airflow through the radiator is reduced.

[S14DB]

Originally Posted by hotboiblaze

this is what ive heard from a lot of ppl that track their cars. however ive also heard (& speak from experience) that @ a stop, ie traffic light & 'pit stop areas'.... vented/raised hoods do help to allow hot air to escape from under the hood.

Yeah, it will let heat out when the car isn't moving. But, will force air in when moving. Fighting the air coming trough the radiator. I'm sure it works great for Drag and drift where you do a quick run and the radiator doesn't heat up. Then cool off in the pits.

Vents in the hood should be behind the radiator and in front of the engine. I have seen a ton of vented hoods for the 240sx over the coil packs or core support. Just because they look cooler there on the out side.

Also, mentioned earlier. Make sure you have a under tray/panel from the front bumper to the subframe/crossmember. As air enters the bumper it will look for the easiest way out. If there is no panel between the bumper and core support it will hit the FMIC/Radiator and go straight down. There is low pressure in the engine bay from the air rushing under it. If you block off the front half from the ground it will suck air through the radiator then out behind the subframe. No panel behind the radiator and you will get air coming up spoiling the low pressure zone.

[ROOSEY]

well i learned something today thank you for the correction!