The exhaust note is all that gives it away. For Alvin Gogineni, the contemporary note that distinguishes his 1967 Datsun roadster is a soundtrack he's fallen for. You see, under that long, scooped nose is the unmistakable twin-cam burble of Nissan's venerable SR20.
Gogineni's desire to bridge modern technology with an old chassis has nothing to do with stealth, speed, or swagger. His motivation comes from a purist's love for the lines of a classic sports car and the dedication to preserve the roadster's original spirit with an infusion of modern technology.
Having never restored or converted a car, Gogineni was smart to focus on finding a car that was ready for becoming a project and not a project hoping to one day become a car. "As soon as I found it, I saw the paint was perfect and the interior was great. It was the right place to start."
Gogineni's Datsun came with an original, yet anything but stock U20 motor. On an early fun run, the low-slung competition oil pan was holed by a stone; and while the engine wasn't hurt, the idea of swapping to a modern powerplant was cemented.
The dollar figures thrown at him for the hot rod U20 made the decision even easier. "I got $3,500 for my old motor, so I could have bought three more SR20s with the proceeds!"
He'd seen a lot of Datsun roadsters with KA24 or SR20 engine swaps, but since he'd never encountered an SR20 roadster with VTC (Variable Timing Control) in the Bay Area, it became his only choice.
"A lot of people do the KA24 or SR20 (without VTC) conversion. The KA24 is a bolt-in solution and doesn't require a ton of hassle. If I was going to spend a lot of money and challenge myself, I figured the S14 Silvia's SR20 motor with VTC was worth it," Gogineni says.
Knowing his mechanical skills were still developing, Gogineni wisely enlisted Bay Area Datsun wizards Rob Fuller and Dan Gallmeister of Z Car Garage to help with the conversion.
Unlike the easier roadster swaps, the SR20 requires a fair bit of notching and welding to fit the engine bay. The pristine body was kept on the frame, making the swap even more difficult. To clear the oil pan, the lower crossmember had to be cut and boxed. Similar mods to the frame were also needed to fit the Silvia's transmission, which is fitted with a B&M short shifter, and matched with a JWT aluminum flywheel and heavy-duty clutch. The rear-wheel-drive exhaust manifold wouldn't clear the steering column or firewall, so a front-wheel-drive SR20 manifold was sourced to cure the territorial dispute.
The greatest swap challenge was still ahead. "We were able to perform the mechanical conversion, but the Datsun engineers who designed the 1967 electrical system couldn't have imagined it would ever need to run Variable Timing Control." Thankfully, Jim Wolf Technology supplied a first-generation 240SX ECU to provide spark and fuel mapping. Controlling the VTC would call for a very unique application of a JWT product.
The roadster lacked a modern speed sensor to trigger the VTC, so Clark Steppler of JWT looked to the company's Nitrous Control Module to engineer around the input signals normally received to activate the VTC. The first major change was to wire the Nitrous Module to accept a signal feed for rpm rather than vehicle speed. Then the module's output was tweaked into activating the VTC. Genius.
Throttle position and water temperature were then routed through the JWT Nitrous Module. With all three feeds sent to the 240SX ECU, it now controls the variable timing engine as if VTC had always dwelled beneath the hood of this roadster.
To ensure the SR20's cooling needs are met, a new C&R Racing radiator was fitted, in addition to two SPAL high-flow electric fans. And to keep the motor breathing properly, Gallmeister fabricated a custom cold-air plenum to mate with the Silvia's high-port intake.
Gogineni next turned to the cabin. Reupholstering and replacing the interior, he sourced modern retro-look electric gauges from Classic Instruments to retain the dash's original analog look while displaying the SR20's vitals.
NISMO suspension springs and a front anti-roll bar, plus KYB shocks, complete the transformation. Front brake calipers and rotors from a '75 Volvo 240 improve the marginal stopping power, while the car retains its stock Datsun rear drums.
Easing between city blocks in second and third gear, the roadster is mild-mannered. The SR20 is as smooth and tractable as any modern Nissan engine. Below 4500 rpm it's docile and friendly. But between 4500 and 7000 rpm, its smoothness is replaced by winding cams that never tire. And it propels the lightweight roadster to speeds the old chassis wasn't designed for.
But the two different eras of Nissan technology can't be ignored. The spinning SR20 serves to highlight the shortcomings of this cross-era transformation. With all of the new revs pushing the driver forward, the old brakes struggle to slow the roadster effectively. Even launching from a stop sign, the next stop must be planned well before releasing the clutch.
The second major point is that the modern, progressive-rate front springs don't mesh with the covered-wagon-era leaf springs in the rear; bumpy roads or sharp steering inputs make driving the hybrid roadster an adventure in car control. Despite the NISMO suspension package, as the front of the roadster rolls over a bump and gently compresses, the rear prairie wagon suspension bounds over that bump like, well, a prairie wagon.
With the rear bouncing, and the front swaying left to right in response, the long front fenders wandering between lanes will keep the driver alert. The marriage of nearly 40 years of automotive technology is at odds, but it's still cool.
Improving the brakes is next on Gogineni's agenda. Nissan 300ZX calipers and rotors will be mounted up front. In the rear, Gogineni has some rather unique plans: The entire rear drivetrain will be swapped for a Ford 9-inch rear end, Ford differential, custom axle and tubes, and matching 300ZX calipers and rotors. To take advantage of the new brakes, Gogineni plans to fit bigger 16-inch Panasport wheels.
Gogineni fulfilled the dream of every Datsun geek when he recently met Datsun Racing legends Pete Brock and John Morton at a local club event. Both of their autographs adorn the main roll hoop; Brock noticed the BRE sticker Gogineni placed on the hoop and inquired if the roadster started life as an old BRE car.
Between John Morton asking to sit in the car and Pete Brock giving him suggestions on what Panhard bar to mount, Gogineni knew his passion for retaining the spirit of the original roadster was a success. He has no plans to sell the car.
If you ever find yourself in Northern California and come across a jet-black roadster making repeated passes through mountain tunnels or underground parking lots, it's likely you've found Alvin Gogeneni making music. With the SR20 wound to its redline and reverberating off the walls, he still can't get enough of this family airloom.
1967 Datsun RoadsterEngineEngine Code: SR20DEType: Inline four, aluminum block and headExternal Modifications: K&N filter, custom cold-air intake piping, ceramic-coated exhaust header from a FWD SR20DE, custom collector, ceramic-coated heat shield, Borla muffler Engine Management Modifications: JWT 240SX ECU with Nitrous module to control VTC switch, Nissan 280ZX electric fuel pump to support EFI
DrivetrainLayout: Longitudinal front engine, rear-wheel driveDrivetrain Modifications: JWT 9-lb. aluminum flywheel, JWT heavy-duty clutch, shortened/balanced driveshaft, B&M short shifter, Nissan KA24DE clutch slave cylinder
Suspension Front: 860-lb. NISMO competition progressive-rate coil springs, KYB Gas-Adjust shocks, NISMO 23mm anti-roll barRear: NISMO competition leaf springs, KYB Gas-Adjust shocks
BrakesFront: Volvo four-piston calipers, 11-in. rotors, Porterfield R4S padsRear: Stock drums with new wheel cylinders and Nissan pads
ExteriorWheels: 14x6-in. Panasport FS, +15mm offset Tires: 195/60-14 Falken Azenis