George Darling's 1988 Porsche Turbo 951In 1988, three years into production of its 217hp 944 Turbo (951), Porsche released the 951 S with a 250hp engine that later became standard on all '89 951 models. It was easily one of the top 10 fastest cars on sale at the time, netting acceleration numbers close to the likes of the Lamborghini Countach, Ferrari Testarossa, Porsche 911 Turbo, and Lotus Esprit. And thanks to a vast aftermarket industry catering specifically to this model, numerous 951 and 951 S cars on the road are fast even by today's standards. This red one, owned by George Darling, is one of the elite.
Red DragonHaving owned two previous '89 951s, including the last one that netted around 400 hp to the wheels, turbo-fueled withdrawal symptoms made Darling realize that he'd made a big mistake by selling them. Soon after, he ended up with this one, which quickly saw a hefty 420 whp at 23 psi with a different turbo. Bitten by the bug, Darling shipped his car to Speed Force Racing where Tim Richards and Shane Johnson used their fabricating expertise to take things to a whole new level.
Basic upgrades like Fikse FM10 three-piece forged aluminum wheels wrapped with wide Falkens were installed. With so much tire, mechanical grip under braking was significantly better than stock. To help stabilize the higher braking temperatures, a set of red Porsche 993 Twin Turbo calipers were also fitted.
More grip means more dive under braking and more body roll through corners. To help counter this and maximize tire performance, a set of Bilstein Escort Cup coilovers were deployed along with Porsche's optional M030 antiroll bars.
Inside the engine bay is a work of fabrication art that rivals pro-level racing teams. At its heart is SFR's custom turbo system. The GTK-650 turbo pumps air into a 3.0-liter block (which replaced the 2.5-liter original) with Nikasil-coated cylinders-a process rendering a hardened surface that doesn't peel and is more wear-resistant than steel sleeves. The extra displacement spools the gigantic turbo with reduced lag and the earth-turning power is repeatable, thanks to Mahle forged pistons, Wossner connecting rods, and ARP fasteners.
A cylinder head from the naturally aspirated Porsche 944 2.7 liter (chosen for its freer flowing characteristics) was ported and polished to further improve flow. With anticipated power levels that most 951 owners would never believe, a larger radiator and oil cooler joined the upgraded cooling systems.
In order to fit the turbo, SFR created a completely new intake system, including an intake manifold housing a 75mm throttle body from a Porsche 928 (the stock one measures 52mm). On the exhaust side, gases exit through SFR's stage two equal-length headers and crossover pipe, and into its 3-inch dump pipe. Up to this point, all exhaust piping is 321 stainless steel to cope with the tremendous heat. From there, the Lindsey Racing test pipe and SFR muffler direct the exhaust, which shoots out the rear with a motorist-frightening fire-fart.
Making everything run in synch is an Electromotive TEC-GT standalone engine management system tuned by SFR for spark and fuel. SFR felt the MAF (mass airflow) system and stock DME and KLR (Porsche's boost brains) computers don't provide the tuning flexibility of the TEC-GT system, and would hinder performance.