How it was done

This is the only inlet on 305 carbureted engine in Budget 'Bird for fresh air. Quite restrictive, especially when the hood is closed.

Factory air cleaner top is different for '87. New parts don't use a wing nut as used to be the case, but now use a twist nut with a metric stud on the air cleaner side. When getting used parts from a salvage yard get a stud and wingnut from an early model Q-jet. Part of the stud that goes into the carb is standard thread and older stud will screw right in.

Hood insulation has to be removed in order to gain access to scoop inlet. Insulation is held in place with these plastic buttons and can be removed with a pair of pliers. If you're careful they can be reused.

Now you see it, now you don't. Pontiac makes it easy to take scoop block-off plate out. Four screws removed and that's all there is to it. Remember screws are metric. Save screws and block-off plate in case you live in a cold climate and snow and rain are a problem.

After removing factory '87 air cleaner lid, we had to find some sort of seal that would fit around outside edge of air cleaner base. Part we used is the firewall to hood seal from a '74 Buick Apollo with air conditioning. Nice thing about this particular part is that it has little aluminum tabs in its base to help it form to the surface it is being used on- bends around corners very well.

As you can see by this photo, seal fits around air cleaner base quite nicely. Tin snips cut off portion of seal we couldn't use and then silicone sealer was applied to join two ends together to form one piece seal.

After a trail fit it was determined that we would need more height than our particular seal provided at back edge where seal is joined together. Another inch was needed, so we took seal that fits on the back of the hood of Budget 'Bird that isolates engine compartment noise and heat from the fresh air going to the interior of the car. This gave us 1.25 inch height gain, which proved to be enough. Remember to replace the hood seal on the Firebird as it gets quite noisy and very warm in interior compartment without it.

New air cleaner lid came from 250-cid single barrel carb six cylinder Chevy in passenger car. This lid is just a shade larger than 12 inches in diameter which also happens to be diameter of stock air cleaner element for 305 that's in Budget 'Bird. Perfect fit.

Shaded area is where the aluminum panel goes to make fresh air chamber. In our experience it is best to use 6061 T6 aluminum that is about 0.060 inch thick. 6061 is very easy to work with and conforms to any irregularities nicely. In order to find out exactly where hole should be cut for air cleaner opening, we put a light coat of lithium grease on air cleaner seal and then slowly shut hood after securing aluminum sheet to hood temporarily with sheetmetal screws in each corner. Remember to cut hole 1/4 inch inside of grease mark, so edge will seal properly. After the hole has been cut, secure plate to the hood with silicone sealer along border and with sheetmetal screws at corners and along long edges.

Here's finished fresh air induction air cleaner setup. Fresh coat of paint on six cylinder air cleaner lid and hood seal on stock air cleaner base, give it that factory look. Using stock air cleaner base retains factory emissions control equipment.

This setup provided an 18 hp increase at the rear wheels, even though Budget 'Bird was on a stationary chassis dyno, and not taking full advantage of the 'air induction' effect. By switching to a taller filter element and increasing the diameter of the hole in the aluminum plate, they were ultimately able to gain an additional 12 hp at the rear wheels; this came after the addition of Edelbrock's TES and factory 3" catback exhaust, along with the Performer (3701) EGR intake manifold.