Exotic composite materials and billet aluminum would never be things one would associate with classic cars, but for Watanabe-san of Rocky Auto, these words are music to his ears. Forget your nostalgically restored old school rides, Rocky Auto does things its own way when it comes to fixing up classics, and the shop's latest creation raises the bar well over anything it has ever done before. Weight saving was a key objective on this dry-carbon-bodied S30 Fairlady Z, but it's what lies under its ultralight skin that will really leave you speechless.
Most of Watanabe's projects are financed by wealthy customers who want to create the classic car of their dreams, based on vehicles they lusted over during their teenage years. Using modern components - be it engines, brakes or suspension - Rocky Auto not only makes older cars more fun to drive, thanks to the additional performance, but also makes them safer by allowing them to handle better and stop more efficiently. This may be considered blasphemy for those who believe that vintage machinery should never be fettled with in these ways, but you really can't ignore the cool factor of cars of this caliber.
After the 600hp RB26-powered S30 Watanabe made for the Tokyo Auto Salon earlier in the year, he wanted to concentrate on using all of his company's expertise to create the ultimate driver's Fairlady Z. Balance was to take over outright power to help make a car that would tantalize the senses with just the right amount of performance. Weight saving came courtesy of custom-made carbon body parts that replace the thick steel panels of the 36-year-old S30. Watanabe didn't cut any corners by using cheaper wet carbon, he had every panel molded and subsequently formed in lightweight dry carbon, which for anyone who doesn't know, has to be vacuum-sealed and pressure-cooked in an autoclave to guarantee its rigidity.
Looking at the car head-on, there's nothing other than tantalizing composite fibers to see as the bumper, front splitter, hood and front fenders have all been replaced. Even the headlight bezels are dry carbon, finished off with slightly smoked acrylic covers shielding the Rocky Auto projectors. Even the riveted-on overfenders are carbon, as is the Rocky Auto dry carbon hatch, which joins the taillight and number plate panel at the rear.
The roof, doors and some of the rear end were left stock since they are an integral part of the chassis itself, but they've been wrapped in 3M carbon look vinyl to help the rear blend in with the real carbon front end. Rocky Auto carbon mirrors are the final pieces in the intricate exterior transformation, which has kept the S30 looking very standard - except for the actual material, that is. The wheel of the moment for any classic car was the natural choice for this project, a set of deeply dished Volk Racing TE37V, where the "V" stands for vintage. These were chosen in a15x9-inch size for the front and slightly wider 15x10 inches at the rear. The Toyo Trampio semi-slick tires are a great touch as they have a very classic design about them with an angular tread pattern and big chunky, rounded sidewalls when chosen in 205/50R15 front and 225/50R15 rear sizes.
Watanabe explains that for years they have been upgrading the suspension on S30s via borrowed components from various generations of Skylines; everything from complete subframes to suspension links and arms have proven to be a cheap and very effective way to inject extra feel and performance into the aging S30 chassis. But the carbon Z called for something far more advanced. Watanabe had a complete custom rear subframe created, first carefully designed in CAD and then precision-cut from billet aluminum to guarantee the best performance. This is joined by billet aluminum front and rear lower arms and a host of other linkages that give the S30 incredible precision coupled with yet more substantial weight savings. Joining these modifications are the Rocky Auto adjustable dampers, valved and especially set up to take into account the car's lower mass. Since weight is just over 2,200 lbs, braking requirements were perfectly satisfied with a set of overhauled Nissan R32 Skyline 4-pot calipers at the front and 2-pots at the rear. These also clear the tight confines of the 15-inch TE37V, a size that's perfect for that true old school look.
The work to the suspension might be unlike anything anyone has ever seen on this level of car, but the engine bay is bound to drop more jaws. Over the years Rocky Auto has swapped all sorts of engines - from Nissans and even Toyotas - into the S30 chassis, but the shop wasn't going to go for just any run-of-the-mill engine on this one. The RB30 was deemed the best choice for this application, a motor that was created using an RB30 block imported from Australia, and fitted with an RB26 twin-cam head. The only modifications made to the engine are the cams, 270-degree bumpsticks fitted to both the intake and exhaust sides along with adjustable HKS cam pulleys. The engine might be modern, but the way in which fuel is supplied isn't, as the electrical injection system and ECU management has all been eliminated in favor of a triplet of 50mm Solex carburetors, custom-fitted to the intakes. These are fed via the Nissan Stagea fuel pump and custom laid braided lines. The exhaust manifold is a work of art, a 6-into-1 design that mimics the curves of the headers used on older engines like the S20 and L24. It then connects directly to the Rocky Auto custom stainless steel exhaust system, which doesn't really have much in the way of silencing. The sound of this RB30 is simply breathtaking, mixing an uncanny resemblance to engines of yesteryear in its response and induction noise with a smoothness and urgency of a modern race-bred motor. After fine-tuning, it now develops a more than adequate 300hp punch. Looking at the gold-topped RB sitting in the vast engine bay, it's obvious that a lot of work went into custom-fitting it; sitting on custom mounts about 20cm back toward the firewall compared to usual installations, it also sits about 5cm lower to help create a true front mid-ship layout. The driveline was the final piece of the puzzle with a 5-speed Nissan transmission borrowed form an R32 Skyline and slightly modified with an OS Giken close ratio gear set, which brings the first three cogs closer together. An ATS carbon plate clutch and Cusco LSD finish things off in the rear.
The interior is more akin to a race car than a road car, with a custom rollcage and plenty of additional chassis bracing and spot welding to help make it more rigid. The Bride buckets are fitted onto the bare metal floor and the heat shielded transmission tunnel protect both passenger and driver from the radiating heat of the engine and transmission. The three central air vents have been converted to house the Omori gauges, while a pair of smaller Auto Meter gauges keep an eye on fuel level and pressure. The stock speedometer has been left intact but is joined by a large Auto Meter rev counter with warning light, as the carbed RB30 has no kind of rev-limit control so the big red flashing light is something you really want to keep an eye on.
It might no longer be considered a true classic by the die-hard aficionados out there, but you just can't help but marvel at the amount of painstaking work that has gone into creating this Carbon Z. Content with the way the car has turned out and its performance, Watanabe has just put the car up for sale and is already thinking of his next project. We can't imagine how he will top this!
Specs & Details
'74 Nissan Fairlady Z
Engine RB30 engine block (2,960cc), RB26DETT twin cam head; Rocky Auto custom engine mounts & positioning, 270º camshafts (interior & exterior); HKS adjustable cam pulleys; Solex 50mm carburetors; custom aluminium funnels; Rocky Auto custom throttle linkage & aluminum pivots, 46mm stainless steel 6-into-1 custom exhaust manifold, stainless steel exhaust system; Stagea fuel tank, in-tank fuel pump; Braided fuel lines; Spitfire direct coil packs; Rocky Auto custom radiator, custom oil catch tank
Transmission Nissan R32 Skyline 5-speed transmission; OS Giken close ratio gear set (first 3 gears); ATS carbon clutch; Cusco LSD
Suspension & Brakes Rocky Auto adjustable suspension, solid bushes, custom billet aluminium rear suspension member, billet aluminium links, billet aluminium lower arms, stabilizer bars, custom tubular front subframe, reinforced front struts & engine bay; Nissan R32 Skyline 4-pot front calipers & 2-pot rear calipers; slotted front brake discs
Wheels & Tires Rays Engineering Volk Racing TE37V 15x9" (f), 15x10" (r), Toyo Trampio 205/50R15 (f), 225/50R15 (r)
Interior Rocky Auto spot & seam welded chassis, rollcage; Bride carbon bucket seats; Sabelt racing harnesses; Momo Corse suede steering wheel; dry-carbon door cards; Auto Meter Sport Comp rev counter; Omori Meter gauges: oil temperature, water temperature, oil pressure; Auto Meter fuel pressure gauge, fuel gauge; custom manually operated heating system, centrally mounted battery