Vented hood?

[UNGN]

We've run the 90's Pontiac GP vents on our hood for 14 years now and they work excellent. I used a Dremel sanding drum to remove the casting flash in the openings and open them up for more flow, but you can't really tell from the outside.



Here are some pictures of the top and underside of our GP vents:




You can literaly see the heat coming out of them. We run a ZZ502 and have covered over the top grill opening for aerodynamics, but the motor stays @ 160 under the worst conditions and there is zero rise of the car nose at speed.

For location on the hood, you want the place with the highest velocity air flowing over it and the largest plenum of air under it. Air slows down at the center of the hood as you go towards the windshield, but has to speed up to break over the fenders or around the sides of the windshield... so middle, forward of the motor is good, as is the sides of the motor as you go back. A vent right above a shock tower, AC box or inner fender won't be as effective as one above the headers where there is less resistance to air movement under the hood.