Author: Paul Romanych a.k.a. RedSS
Ram Air/Cowl Induction for your 454SS
Choosing the right hood
Science experiment: Try taking a deep breath through an average soda straw. Not too easy is it? This is basically what your SS has to accomplish with it's stock intake system. Now take a de
Science experiment: Try taking a deep breath through an average soda straw. Not too easy is it? This is basically what your SS has to accomplish with it's stock intake system. Now take a deep breath without that straw in your mouth (for those of you that live in a smog-choked area like Los Angeles or New York City, the State of California wants you to know that this action might be harmful to your health). If you live in a clean area of your state or country, you should feel heartily refreshed afterwards. This is how your SS will feel after you chop the stock intake system and add a new system to help it breath easier.
There are many alternatives to get more outside air into your motor, as it is optimal to duct in cooler, more oxygen-rich fresh air, rather than drawing hot oxygen-poor air from the engine compartment with an open-element air cleaner. One in particular that will use a minimum of duct work to direct airflow, is to install a cowl induction or ram-air hood so the engine can draw air directly from the outside of the engine compartment. An added benefit of an induction hood (be it "ram-air" style, cowl induction style, or via a hood scoop) is that as you drive faster, more air is pressurized in the intake tract, thereby "force feeding" your motor an additional charge of air, proportional to the amount of air the engine needs. Plus an induction hood just has that timeless hotrod appeal that oozes with coolness.
For this buildup, I chose a cowl induction hood, to give my 454SS a look that dates back to it's muscle car heritage in the SS Camaros, Chevelles, and the like, and to keep it smooth and clean. Some other hotrodders might prefer a later-model Camaro-style ram-air hood. Others might find they need a hood scoop to clear some air cleaner assemblies. It is nothing more than the preference of the buyer.
One consideration that is not simply preference is hood material. Realistic, affordable hoods are made out of two materials: steel or fiberglass. Steel hoods are typically more rigid and heavier than glass hoods, and most are a direct bolt-on for the stock hood. Steel hoods also do not require retaining pins on the front of the hood in most instances. There is some variance of quality but most steel hoods are of good to excellent quality, and your body man is probably better suited to work with steel than glass. On the other hand, fiberglass does not rust. Fiberglass does not dent. You can pick up a fiberglass hood (even a superb quality hood). By yourself. A good quality bolt-on glass hood also does not need hood pins to keep it retained. A great quality glass hood costs about the same or less than a steel hood, and due to the lighter weight, costs less to ship. Glass is my choice. Our options- and metal-laden 4800 pound (most of which is in the front) 454SS's need all the weight reduction they can get. Choose your material. Goodmark makes some of the best steel cowl hoods at glass-competitive prices which feature a 2" rise, cowl screen, and boasts an extremely OEM-like fit. They can be reached at 770-339-8557, website www.goodmarkindustries.com. Harwood is THE name in auto fiberglass and Lexan, and they can be reached at 1-800-882-7223, website http://www.martelbros.com/harwood/harwood.
Now with your hood selected and delivered, it is time to fit it on your vehicle. Steel hoods, if you bought a good quality one, should fit right onto the stock hinges, and only require adjustment and possibly some shimming to get the hood in the proper location before you prime and paint. Steel will typically come with a protective black paint coat to prevent rust during shipping. Goodmark notes that their protective coat is meant to be sprayed over, like POR-15 rust preventer is.
Fiberglass requires more prep work. Unlike steel, fiberglass hoods are not stamped out, and thus, must be trimmed, sanded and otherwise fit to the specific vehicle it is being installed on. First, you must remove the stock hood and hinge springs. If it is a bolt-on hood, operating like the one you are removing from the truck, you will be using all of the hardware from the stock hood on the new hood (a sidenote: unless you are building an all-out race truck, you will probably want the bolt-on hood rather than the lift-off or pin-on style hood that requires removal of the hood every time you want to access the engine bay). Now, lay on the new hood and check for fit. The edges of the hood will need to be trimmed. This may be done with a block sander and coarse sanding paper (80 to 120 grit). Sand off a little, then check again, sand a little more and check, etc. until you have the proper fit and finish. Our trucks have a cowl vent between the hood and windshield. Harwood recommends trimming the back edge of the hood to fit this cowl vent as the stock hood did. Once the hood fits perfect, you are now ready to bolt it on the hinges. Bolt it to the hinges, and the hinges to the truck, and check again for clearance.
Included with earlier style Harwood hoods and some other lesser-known brands of hoods is a prop rod. This is intended to hold the hood up, basically taking the place of the hinge springs, as the springs will not be re-used (for steel hoods and for some glass hoods, like the revised Harwood hoods, they are, but most other glass hoods will not withstand this usage). Install the prop rod on the radiator support rail. Harwood said this prop rod is a universal fit, so it is necessary to trim it to fit. Position it in the middle of the hood so as to prevent the hood from twisting while it is on the prop rod. If you position the prop rod to the side, you run the risk of twisting and cracking the hood or paint job.
For the later, revised Harwood hoods the company notes that prop rods are not necessary. I spoke with Ray Martel, president of Martel Brothers Performance who owns Harwood, and he said that the bolt-on hoods for many applications have been redesigned and strengthened, allowing one to use the stock hinge springs. If you do not receive a prop rod with your hood, it does not need one, he says.
Now you are ready to install the hood latch and spring on the front of the hood. Position the hood and adjust it in using the bump stops and adjustment screws. Check again for fit and operation.
After you drive around for a week (or if you are like me, let it sit in the sun for about a week and a half) with an unfinished hood sitting atop your otherwise pristine SS, to allow the gelcoat to stabilize and the fiberglass agents to bond and cure, your truck is now ready to be shipped off to your body shop for finishing, priming, and painting.