I purchased this recreation Porsche 904 from Martin and Walker in England several years ago. Barrie Martin was reconstructing an original damaged 904 using original chassis prints when he got the idea that he might as well make entirely new cars. He now sells the cars under the name Technik. Mine was his sixth, I believe.
I used to own a real 904, a Porsche team racer, and I copied the interior color scheme from that car. We made the driver's seat from molded foam to get my body down low as the 904 does not have a lot of interior height. The gearshift is a bit awkward (as it was on all the 904s), but otherwise this thing really moves.
The car was built with the external visual cues of the late 1964 production four-cylinder 904s, but actually has a six-cylinder 3.0 litre 911SC motor and a SC 5-speed gearbox. Barrie uses an exact copy of the stamped-steel chassis, bonded body and suspension arms and uprights, but with 911 SC vented disc brakes. My motor was built by Arizona engine builder Drew Salter with Webers, 911S cams and 11:1 pistons, so it runs awfully fast.
The visual cues of a late 1964 four-cylinder 904: small air scoops forward of the rear fenders, the later, molded-in rear tail lip, small rear fender flares, and the radial exhaust mufflers. Barrie also installed small reverse-flow mufflers within the engine compartment, like the original cars, so the car does not make an awful racket and is almost pleasant to drive.
The diagonal black tubular braces running from the top part of the roll bar hoop back and down toward the rear shock towers are not original, but most of the vintage-raced original 904s have added these for safety. We replaced the original rear body section parallelogram hinge mechanism with a simple aluminum tube. The wheels are all steel whereas the originals were magnesium/steel.
John Horsman (FAV's former chief engineer) calculated gearbox ratios so we could have proper overlap in each gear. The car will hit 160 mph at 6,850 rpm. The 904, even with a two-liter motor, could pound the Cobra roadsters on twisty and uneven circuits like the Targa and Nurburgring, not only because it handled better, but also (see Ben Pon's comments on page 155 of the book) because it was easier on the driver. On a fast track (like Spa, see page 143) the two cars were very close.