This post is a continuation of the work Don Ostergard did to the original IFG body.
One of the biggest telltale signs of an IFG kit is that the portion of the rocker panels below the doors is actually an integral part of the door skin, as mentioned earlier.
One of the biggest telltale signs of an IFG kit is that the portion of the rocker panels below the doors is actually an integral part of the door skin, as mentioned earlier.
This means the rocker panel which should be one continuous piece stretching from front to rear wheel wells, is actually in three pieces: a small portion between the front fender opening and the front door edge (green), a long section attached to the bottom of the door (blue), and another short section between the rear edge of the door and the rear fender opening (yellow).
It seems easy enough to cut the three pieces from their larger panels and attach them together to form the proper one-piece rocker panels, but it's not as simple as it looks. First, the door sill (below, in blue), which is usually an integral part of the rocker panel doesn't exist and must be fabricated. Second, the IFG rockers don't extend under the car (orange portion) so the bottoms are wide open to the road for wind to buffet, vibrate, and crack them. And lastly, there are no integral ribs or stiffeners (green) inside the rockers to provide proper attachment points to the chassis, as well as to support the ductwork for the rocker scoop. In fact, the IFG rocker scoops are quite shallow and were obviously meant to be decorative rather than functional.
So the first thing Don did after he chopped the rocker pieces from their original panels was to bond them together. Then, he temporarily mocked them up to the chassis and bonded wide door sills to them:
He fashioned the sill plates from masonite, presumably as templates to be replaced by fibreglass, though he didn't get around to it by the time he sold it to me.
This next photo shows a portion of the passenger side rocker upside-down, while looking at the original rocker scoop from the inside out. It shows a few things: First, how the rocker's outside bottom edge has a simple return flange, but doesn't have an underside panel to close the rocker off from the road. Second, it shows how shallow the rocker scoop was made, and by its rounded rear shape, wasn't meant to be opened up:
Don wanted functional rocker scoops so he cut them open and fabricated some sheet metal forms in the shape of deeper, gaping ductwork on the backside of the rockers. This photo shows the bottom of passenger rocker standing upright on it outer surface:
Once he was happy with the fit, he glassed over the metal ductwork to form a fibreglass funnel:
He also created a fibreglass stiffening wall or rib to support the end of the new duct. Here's a look down into the scoop from the rear looking forward once the fibreglass had cured and the metal form pulled out:
And here's the view from the outside looking into the newly formed intake:
It needs some finessing, however it is significantly larger, longer, and more functional than the IFG decorative scoop it replaces.
The last thing Don did to finish off the major reconstruction of the rockers was to close off the bottoms. Here, he used coroplast (white corrogated plastic) panels to rough out the shape needed to seal up the bottoms:
Then he applied a mould release wax to the plastic and glassed over the coroplast from the inside:
Once the resin had set up, he removed the coroplast form and was left with the completed fibreglass bottom panel. Here's a shot showing how the bottom panel neatly fits up against the chassis underbody framerail:
And finally, a photo of the rough-finished rockers with all the modifications completed: