Screw-Out Hood Vent
	Category:	Performance
	Author:	MachineMan
	Date:	November 17th, 2005

This write up explains how to put a removable port (vent) in your hood to let some heat escape. Most install louvered vents but they can leak water when it rains so I opted to install a marine deck plate which can be removed during hot days and closed back up when it’s colder and/or raining. The idea isn’t new but it super easy and cheap to do. The write up is based on a ’90 Jeep Cherokee but will work for most any vehicle.

Parts
Deck plates come in several different sizes, types and colors. You can check them out at www.Beckson.com. I chose a screw-out 4” opening deck plate. If you want more cooling you could install a 6” or maybe two 4” plates. They can be purchased at most marine stores or online for <$10. They are made from UV resistant polypropylene and are sealed with an o-ring.

Parts I used:
1 - 4” Beckson polypropylene screw-out deck plate, black (DP40-B)
6 - #8 x ½” Stainless Steel panhead screws

Deck plate

Installation

1. Decide where you want to mount the vent. I chose a location above the intake and exhaust manifold where it gets the hottest. The heat will be forced toward the fire wall while driving so the farther back the better.
   
2. Using the radius of the deck plate to ensure that the vent won’t interfere with any of the hood support ribs, drill a small pilot hole for the center.
   
3. Mark out the circumference using the pilot hole as a center point. Make the diameter just larger than the inner flange but not bigger than the bolt pattern. Then drill a larger hole at the edge so you can start off your cut there too.
   
   
   
   
   Hole marked out
   
   
4. Inspect the area under the where the hole is to be cut just to make sure you don’t accidentally cut any thing else; hood release cable, intake hoses, etc…
   
5. Cover the engine and cowl vent so no metal shavings fall in there and cut out the hole. I used a Sabre saw. If you’re concerned about scratching the hood then put masking tape where the saw will ride.
   
   
   
   Hole cut out
   
   
6. Dry fit the deck plate and drill out the screw holes. For #8 screws use a 7/64 bit.
   
7. If you're concerned about rust then put some primer on the cut surfaces.
   
8. Apply some Silicon or water tight sealant to the under side of the plate and screw it in and your done.
   
   
   
   Vent plate installed
   
   
   
   Inside view of plate installed
   
   Tom K. Sept. 2005