Liberate the Harwood hood from its box, and you’ll be shocked at how light it is--around 16 pounds and easily manageable by one person. Our first advice is to do all the fitment work on the hood long before you get either it or the car painted. We choked on that score and had both the car and the underside of the hood painted before we realized that was a bad idea. Begin by dropping the hood in place and checking the fit. It won’t be perfect at first.
The Harwood instructions indicate that the 3/4-inch flange at the perimeter of the hood is for protection during shipping and that it needs to be cut back to 1/4 inch. We judiciously trimmed the fiberglass a bit at a time while continually trial-fitting the hood--better to cut four times than ruin the hood with one wrong slice. Ultimately, we trimmed the entire edge down to no more than an 1/8-inch lip except at the very front, where it’s critical that the body edges line up for the car to look right. We made those cuts once the installation was nearly complete. The hood can be trimmed with a saber saw, but we found an air- powered cutoff wheel to be the perfect tool for the job. Don’t be as stupid as us: Wear a respirator, gloves, and eye protection.
To trim the edges straight, we were able to handhold a marker in a steady position and scribe a guideline down the flange using the smooth topside of the hood as our index. You could also use masking tape to make the line.
As we trimmed the hood edges to fit, we worked first one side, then the other, to make sure the hood would be centered when at rest between the fenders. Once we’d trimmed as far as we could go (a small flange must be left to give the hood some rigidity), the hood was still a hair too wide to fit between the fenders. We used some 200-grit sandpaper on a block to shave the edges down by about 1/16 inch per side. The ’glass is very easy to sand. Even so, we ended up having to readjust the fenders outboard a tiny bit to get the hood to fit smoothly between them.
Rather than old-school hood pins, our glass hood will be held down with 10 Dzus-brand, quarter-turn, self-ejecting fasteners: three along each side, two in front, and two in back. Harwood sells a complete kit that includes brackets (arrow), Dzus fasteners and springs, and rivets.
We decided where along the edge of the hood the brackets would go, marked the center location with masking tape, and measured such that the very top of the bracket was about 1/8-inch lower than the top of the fender. Since the hood is about 1/8-inch thick, this placed the hood-supporting surface of the Dzus bracket in contact with the underside of the hood in the correct position to hold it nicely in line with the fender. We didn’t drill the hole at 1/8-inch below the fender, but measured the distance to the three mounting holes in the bracket.
A good smack on the punch with a hammer marked the drill spot, then we held the bracket in position and measured again to make sure we’d drill in the right place. Hours were spent checking, double-checking, and triple-checking to make sure we didn’t riddle the car with misplaced, hogged-out, ugly holes.
After drilling the first hole, we used the end of a rivet to hold the bracket in position while marking the second and third holes. It’s easier than measuring and more of a sure thing. Once the drilling was done, we still left the brackets loose, holding them in place just by slipping the rivet heads into the mounting holes.
Once the brackets were in place, we marked the centerline and both edges with masking tape.
Here’s why: The next step is to drop the hood in place, and make sure it rests evenly in place. It won’t fit well if the fiberglass flange is hitting the Dzus brackets or any other underhood obstacles. Since our hood hit all the brackets, we used the masking tape as a guide to know where to mark the hood for grinding.
The cutoff wheel was too nasty for the small detail work needed for grinding clearance into the hood, but a sandpaper roll worked quickly and cleanly as we sanded the flange flush with the bottom of the hood at the bracket locations we had marked.
After we were happy with the fit of the hood, and all the brackets seemed to be in the correct up-and-down position, we riveted the brackets in place. Our toolbox was devoid of a rivet gun, so we bought this way-bitchin’ Stanley model with a head that pivots 360 degrees. Our buddies were jealous. Once we popped the first rivet, we found that the steel ones provided by Harwood have only a 1/8-inch reach, not enough to go through the two layers of sheetmetal on the flanges of our fenders. Another trip to the store got us some 1/4-inch-reach rivets, and we stepped up to stainless steel to prevent rusting.
After riveting, we left the masking tape in place to show us where the center of the Dzus brackets were when the hood was in place. Holding the measuring tape in line with the masking tape, we measured 1-1/16 inches from the inner edge of the fender and made a mark on the hood. This is where the center of the hole in the Dzus bracket is--1-1/16 is the same as the distance from the mounting flange of the bracket to the center of the hole.
Using the mark on the hood as a target, we drilled an 1/8-inch guide hole, then hogged it to 3/8 with a bigger bit. The 3/8-inch hole was big enough for us to inspect and make sure wed succeeded in drilling the hole centered above the Dzus bracket underneath. If not, we were able to finesse the drill to the center while bringing the hole to a final size of 1/2 inch.
The holes in the hood are for mounting the body of the quarter-turn fasteners, which are a bit tapered. Because of this, youre supposed to taper the hole with a 5/8-inch chamfer bit. We were able to get the job done by carving the fiberglass by hand with an 1-1/16-inch standard drill bit. Dont attach the fasteners to the hood yet--wait until the hood is painted.
This is the spring that the fastener grabs onto to hold the hood in place. The springs come separate from the brackets so you can pop-rivet them into one of the four locations that’s best for your application. You can tune the position of the slot in the fastener heads with the location of the spring. Be forewarned, though: We found out the hard way that the springs cannot be positioned such that the rivets are in line with the rivets used to hold the body of the fastener to the hood.
As we mentioned, the rivets that will eventually hold the Dzus fasteners to the hood may hit the mounting bracket. We used a 3/8 drill bit to enlarge the holes in the mounting bracket that fell directly under the rivets in the hood. Problem solved.
We began by placing Dzus brackets down each side of the hood. Once that was done, the hood could be held firmly in its final position for another fit check. As these side-by-side photos show, now was the time for us to mark and trim the flange around the base of the windshield and the back of the cowl. We cut the cowl roughly to shape, then finished it off by hand with sandpaper. The fiberglass is very soft and easy to sand, and we also smoothed all the cut edges around the hood so they would look good and not fray after painting.
The step we feared most was the fabrication of brackets to hold the hood down at the front and rear. These are the most difficult to do because there is no place to attach the brackets provided by Harwood, but the front and rear fasteners are critical for holding down the hood at 100-plus speeds. We had to buy some steel and bash it into shape in the vise, and do some fancy drilling to make brackets that would work. The position of the holes in the hood also required some dead reckoning and a little luck. At the rear, we were able to measure an X and Y axis from the edge of the fender and the base of the windshield to locate the precise position of the head of the Dzus button. During all of this, we had to remember not to make any bracket hit the reinforcing rib underneath the Harwood hood.
The last step before paint was to lock the hood down and trim the cosmetically critical front edge of the fender. This relied heavily on our ability to simply eyeball the right look, but we used masking tape to assure a straight cutline. We trimmed it with the cutoff wheel while the hood was mounted to the car, smoothed the edge with sandpaper, and did a pretty dang good job if we do say so ourselves. Since all the Dzus buttons were in place, we also drilled the 1/8-inch holes (using the body of each fastener as a guide) that will later be used to rivet them to the hood. Full race, huh? As with the rest of our El Camino, Gonzalez Auto Body handled the Hugger Orange paint. Owner Gus Gonzalez advised that fiberglass hoods should only be block-sanded by hand and not with a machine to prevent waviness in the soft material. Even so, Gus agreed that the Harwood finish was exceptionally nice. The last thing we had to do was clean out the holes we drilled for riveting the Dzus fasteners to the hood, then pop-rivet them in place using the aluminum-bodied rivets provided in the Harwood kit. It’s important to use the aluminum ones because steel models will pull through the fiberglass. If you get the rivets mixed up, sort them out with a magnet (as you know, it won’t stick to aluminum).
A lightweight lift-off hood: Everyone's got one, right? They're all over the NMCA races, and Harwood's 4-inch-cowl version made our El Camino look faster than it can live up to while heaving a hefty 75 pounds off the nose of the car as compared to the stock slab. That makes it worth it. But to tell you the truth, installing the hood was a bigger pain than we expected, mostly because we held it down with 10 Dzus quarter-turn fasteners instead of hood pins. The installation is complicated, but the old four-pin method lets the hood bow drastically at dragstrip speeds.Another hassle with the lift-off design is having to remove the hood to check the oil, but working on the engine without the hood and hinges in the way is a big plus.
There are pros and cons, but this time we selected a lift-off. The installation gave us the chance to feel like we knew what we were doing, play with Dzus buttons, look like race-car guys, and best of all, show you how it's done. Don't know about you, but we've never seen this in a magazine before. The installation will vary a bit depending on the design of the car, but our info will get you in the ballpark and will apply directly to any '70-'72 Chevelle or Elco.
If the procedure looks like a bit more than you can handle, sweat not. Harwood has hoods that bolt to the stock hinges too. They're slightly heavier and more expensive (by about $180), but far easier to install and live with day to day. Either way, the finish on Harwood products has always impressed us--just look at this month's cover to see how smooth the hood looks after paint.