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Through some random browsing on clubroadster, I came across these headlight vents and I'm really taking a liking to them. Anyone seen any like this is Aus or anywhere for that matter?

Some people think they let more hot air out than cold air in, but those ones certainly look the goods!

iirc those are from zoom eng. give them a search in google.

There has been posts on the big forum where it is believed that these vents pressurise the engine bay and thereby reduce the air flow through the radiator and causing coolant overheating. That car might get around that by raising the rear of the bonnet to allow air to escape, although I believe that is illegal.

J

I was a little skeptical about what it would do to air flows through the engine bay and an increase in pressure/decrease in flow does make sense.

still looks cool though...
More researching to be done!

When I was building the MX5 back in 1999, I had a few different headlight intake covers that I cut up just to test any benefits to power. As my mate (the dyno owner) and I were interested in the results for different headlight intake covers and air filters, we utilised a Saturday morning to do just power runs to test this.

Now from memory, the best headlight intake covers were the NACA duct and the 'RS Aizawa' type for a decrease in intake temps (due to slightly cooler air being drawn into the engine bay) which equalled to slight more horsepower. From memory, the increase was approx 1-3 rwkw. The runs were done on my NA6 turbo on 15psi boost in 4th gear, 32 psi tyre pressure, bonnet down, fan on with 15 mins intervals in 40 degree summer temps.

I don't have the dyno sheets as we never bothered to print it out (thinking that no one would care back then about bloody headlight intake covers). I wonder if he still has the files for my runs backed up....will ring him and ask and try my luck

Either way, I just thought this might give a little more information on the topic.
Hope it helps

looking at the picture perhaps thats why the bonnet is cracked open at the back, to let the hot air out

mx52nv wrote:When I was building the MX5 back in 1999, I had a few different headlight intake covers that I cut up just to test any benefits to power. As my mate (the dyno owner) and I were interested in the results for different headlight intake covers and air filters, we utilised a Saturday morning to do just power runs to test this....

Was that over the intake side? or on the opposite side as well?

I should have mentioned this before, the headlight intake cover was tested on the passenger side

I put the driver's side one on as an addition to air flow after testing the passenger side one for effectiveness.

I think the ones pictured are ZOOM

http://zoom-eng.com/catalog/product_inf ... 122405da06

grump wrote:looking at the picture perhaps thats why the bonnet is cracked open at the back, to let the hot air out

I'm on the side of thinking that this is detrimental as the back part of the bonnet is a known high-pressure area so lifting the rear does not extract hot air but more so takes in cool air.

Oh, and just for the sake of being technically correct, let's call them Headlight Cover INTAKES instead of vents, as intakes TAKES IN air, whilst vents LETS OUT air.... not that I'm being pedantic or anything

1red5 wrote:Oh, and just for the sake of being technically correct, let's call them Headlight Cover INTAKES instead of vents, as intakes TAKES IN air, whilst vents LETS OUT air.... not that I'm being pedantic or anything

You pedantic - Never!

The pictured vents look horrible. The NACA ones look OK.

mx52nv wrote:

1red5 wrote:Oh, and just for the sake of being technically correct, let's call them Headlight Cover INTAKES instead of vents, as intakes TAKES IN air, whilst vents LETS OUT air.... not that I'm being pedantic or anything

You pedantic - Never!

Well since you didn't correct him, I thought I would pick up the ball and run with it.

Just to add something more useful, I have a NACA headlight cover intake on the passenger side, as well as turn-signal intakes, and it has not harmed radiator coolant temps. With the stock cooling route, it shows up max temperatures of no more than 203 degrees fahrenheit (95degrees celcius), that's sitting idle for about 10 minutes, after a decent drive, with a closed bonnet.
Cruising, its around 185degrees fahrenheit (85deg celcius).