Hood Vent to Lessen Underhood Pressure (Page 1/2)
PacNWFiero NOV 18, 12:10 AM
Hello!

I'm wondering if anyone has a suggested/preferred method of reducing underhood pressures at high speeds to help reduce front end lift and headlight pop-up. I've looked at Embrace Racing's cutout aluminum vent (http://embraceracing.com/racespecvent.php), along with a fiberglass graft-on type from Angel on Earth (http://angelonearth.net/customfiberglass/). I have heard good things about the Angel on Earth product, but I'm definitely biased towards a product that doesn't require fiberglassing/grafting or any new painting, so the Embrace Racing one looks pretty tempting. Any ideas?

Thanks!
cvxjet NOV 18, 12:24 AM
I think the hoods of Fieros could use something to break up the large smooth surface, and of course a vent is functional to release pressure from under the hood AND help airflow thru the radiator......But there are a couple of problems with them; The main one is that if you don't have A/C and live somewhere hot, the hot air exiting the radiator goes right in your cowl vent-You could possibly create a flap that closes and opens with a control inside.......Finding one that fits the styling but doesn't require cutting up the front structure under the hood, is another difficulty.

I actually like the one someone did that used, of all things, the dash defroster grill from a Fiero....It fits and matches the theme of the front/windshield/dash shape....

There is also someone who installed body vents(From a 4th gen camaro I believe) in the headlight buckets to vent towards the wheel-wells....Which avoids dumping it into the interior!
tnkgnr NOV 18, 01:13 AM
I was changing the brakes on my BMW the other day and noticed it had channels running from the bumper into the wheel well - presumably to help cool off the rotors. I think you might be able to do the same with the Fiero - at least some overpressure would be vented to your front wheels and have the dual benefit of keeping the brakes cool.
seajai NOV 18, 07:06 AM
I took a pair of trunk vents from a Ford LTD and cut them in to the frame next to each of the headlights to dump underhood pressure into the areas behind the front wheel well liners. I then made custom vent louvers in the liners to exhaust that air. It seems to work quite well, I've had my car up to 115mph and the front end felt stable and the headlight doors didn't lift.
fieroguru NOV 18, 08:14 AM
I did something similar to seajai.
I took a 3" hole saw to the outer edges of the both headlight pockets to make 2 large air holes on each side. Then did the the same to the wheel well liner. I have had my car over 120 mph w/o any noticable front end lift or head light doors popping.


fierosound NOV 18, 11:25 AM

quote
Originally posted by fieroguru:

I took a 3" hole saw to the outer edges of the both headlight pockets to make 2 large air holes on each side. Then did the the same to the wheel well liner.



You don't really need any holes in the wheel well liner.
Air will dissipate from the bottom and the back section by the door.

I did the same as seajai on my GT
http://fierosound.com/moreM...iator%20Area%20Vents

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bjc 350 NOV 18, 11:55 AM
Or, you could just buy this one ready to go, except for paint of course. I have this style on two of my cars. This is similar to Archies Warber style. Works well. No cutting of the inner structure or front trunk bulkhead and everything seals as original at the front trunk edge. Includes the grill for the opening. Located near Clackamas, Or. No shipping. $300
PacNWFiero NOV 18, 12:32 PM
I'll probably go with a 'stealth' vent type like some of the ones posted where they vent to the wheel well. Thanks for the offer on the pre-made one, it looks great, but I just had new paint done and I would like to keep the paint looking new and uniform.
rogergarrison NOV 18, 12:54 PM
The simplest way to let the air out of the headlite covers is what Ferrari did to 308 model. They put louvered covers over the headlights, opened towards the rear. I dont know if that would be enough to prevent body lift. Lots of the sports car series racers like IMSA, have the same style of louvers over the front tires in the fenders. Headlite covers would be pretty easy for some of the fiberglass parts makers on here. Just be a paint and screw on install to replace the original.
cvxjet NOV 18, 01:59 PM
I have always thought that headlight covers with louvered venting would be the best way to go....And being at the edges would mean the hot air would drop over the edges of the fenders- away from the cowl vent.......seems like a simple bolt-on once they are manufactured......