“Raging Waters” – Excellence June 1999

  • “Raging Waters – Gary Stone’s turbocharged water pumpers”
  • Excellence
  • By David Colman

Gary Stone has always been a water sportsman. He sells windsurfing gear through his own direct marketing company. When it comes to Porsches, he’s only interested in water pumpers. So far, he’s owned no less than five of them, all four-cylinder models.

So when a turbocharged, highly-modified 968 came up for sale by way of Kelly Moss Racing Stone figured he just had to have what may well e the ultimate streetable iteration of the 944/968 series. The car has proven to be so fast that his most recent flame, a modified 1989 944 Turbo, seems tame by comparison. But Stone’s infatuation with the 944 and the 968 series isn’t a recent affliction. It started 16 years ago, when the 944 was first introduced to a hungry sports car market.

After reading Car and Driver’s review of the first generation 944 in 1983, he ran out to order one the very next day. When the metallic gray 944 with two-tone brown cloth interior finally arrived some six months later, Stone was “furious because it didn’t have the sport seats it was supposed to have.” The unconcerned Porsche sales staff said, “Fine, don’t take it. We’ve got a year backlog on this car… Next!” Stone took the car and learned to live without sport seats.

When Porsche introduced the 217 hp 944 Turbo in 1986, droves of 944 faithful descended on the dealer network with checkbooks in hand, hungry for an upgrade. Gary Stone was one of them, and, late in 1986, he exchanged his 944 for a 944 Turbo. This time, he made sure his new Platinum Metallic Type 951 was equipped with sport seats and gold-centered Fuchs forged alloys.

During the eighties, Porsche was generating new iterations of the 944 series every few years. By 1989, the available models were an upgraded 944 Turbo and a 16-valve 944 S2. Thanks to the outstanding performance of the new Turbo, the S2 was proving difficult to sell because it cost nearly as much as the Turbo. Gary Stone took advantage of the situation and bought a Baltic Blue Metallic 944 S2 with Linen-colored cloth seats at a significant discount.

Though the S2 was a “beautiful color” and even faster off the line than his 1986 Turbo, Stone’s love affair with water pumpers was about to suffer temporary vapor lock. “After the S2, I got married, and Porsche kind of left the equation for a while,” says Stone of his forced hiatus.

But soon after the birth of his two children, he was lured back into the fold by his old autocrossing mate, Denny Voss, who showed up with a 1988 Turbo S decked in 911 Turbo 3.6 three-piece wheels and augmented with an Autothority Stage 2 chip. “I got the car and drove it – it just blew my mind,” says Stone. “I said to myself, I gotta have one of these!”

Soon, he did. It took six months to locate the car he was looking for. Spotting a likely candidate in a classified ad, he drove to Atlanta and purchased an Alpine White 1989 944 Turbo with a white leather interior in the Spring of 1996. With the help of the racing experts at Kelly Moss Racing (KRM), he converted an already-potent performer into an outstanding track car. Thanks to their long-term involvement with winning 944S2 and 986 entries in the Firestone Firehawk Endurance and SCCA World Challenge series, KMR has accumulated a significant body of knowledge on tweaking 944 Turbos for speed and longevity.

The 944 Turbo upgrade program consisted of beefing up the suspension, brakes, and drivetrain. Jeff Stone of KRM equipped the Turbo with adjustable front roller bearings of KRM’s own design and manufacture. FabCar A-arms replace the stock 944 units, which are failure-prone in competition. A strut-tower brace by Brey-Krause triangulates the upper shock towers.

In the rear, KMR’s bearing kit optimizes suspension geometry for the trailing arms, while Porsche M030 sport shocks, springs, and torsion bars snub suspension movement. Club Sport anti-roll bars impart a touch of oversteer to the chassis otherwise bent on understeer. Also added were KMR anti-roll bar mount braces to eliminate substantial play in the anti-roll bar positioning. KMR lowered the ride height, corner balanced chassis, and set the alignment halfway between steet and track settings for all-around use.

Thanks to 968 M030 brakes, Stone’s 944 Turbo stops consistently true. Pagid RS14 pads handle stopping chores, activated by AP 600 brake fluid flowing through stainless steel lines to each rotor. The contract patch of each tire is well beyond what factory offered on the stock Turbo S. Originally, theese cars were sold with 16×7 front and 16×9 rear forged alloys. On the street, Stone runs B&DW Motorosport Turbo 3.6-style three-piece front wheels measuring 17×9 with rears that measure 17×10. These rims carry Bridgestone S-02 rubber, 235/40R17 front and 255/40R17 rear. For track events, he bolts on a set of 944 S2 wheels, measuring 16×7 front and 16×8 rear. These carry BFG R1 tires measuring 225/50R16 front and 245/45R16 rear.

The biggest modification to this 944 Turbo, however, lies under the hood, where KMR has stroked the 2.5-liter motor to 2.8 liters by replacing the original crank, with one from a 3.0-liter 968 engine. Mahle pistons with 968 piston oilers, Carillo rods, a billet camshaft, ported and polished heads, and a stock K26 turbocharger round out the basic specifications of this mtor, which produces 360 hp and 411 lb/ft of torque on the KMR dyno on 110 octane race gas. This compares to the stock 1989 944 Turbo output of 247 hp and 250 lb/ft of torque. For street use on 92 octane pump gas, the KMR motor still produces 305 hp and 360 lb/ft of torque at the crank.

Some of the secrets that make this turbo so potent lie in the redesign of the intake system. KRM shimmed the wastegate and drilled the cycling valve, but retained a stock flapper box because KMR believed that increased air flow would not provide additional benefit due to the use of the stock turbocharger. Except for a catalytic bypass pipe, the exhaust system remains stock. A Bosch Motorosports fuel pump with adjustable fuel pressure regulator maintains the proper flow of gas for all octrane blends. When race gas is used, the chip must be changed and the fuel pressure regulator adjusted.

Interior modifications make the Turbo more comfortable than stock. Stone ditched the factory driver’s seat in favor of a full-race Recaro SPG seat, but soon found the discomfort of driving to the track in the SPG outweighed its benefit while on the circuit. So he removed it in favor of a more all-purpose Recaro SRD. He attached a five-point Sabelt harness to a Brey-Krause harness bar, then tossed the original airbag steering wheel in favor of a one-inch-smaller Mono Corse wheel. He also disabled the passenger-side airbag.

With these modifiactions, the white 944 Turbo was finally the kind of rocket sled Gary had wanted all along. Here’s how he describes it: “This car drives like no other Turbo I have ever been in. The boost comes on immediately and progressively without lag, and pulls like mad all the way to redline.

“The chassis is so connected to the road, you have to drive it to believe it is based on the same car as a stock 944 Turbo. Steering input is perfectly precise and the car gives you complete feedback all the time. Surprisingly, the ride quality is hardly affected. Expansion joints are a little more lavish but in general cruising, it is actually more comfortable than stock because the stock vagueness is gone.”

What really made the project come to life, however, was the addition of a 968 6-speed manual transmission. In the lower gear ranges especially, the addition of an extra cog works wonders for keeping boost ignited. As the owner says, “When shifting gears quickly, there is no loss of boost.” David Stone, one of the partners at KMR (and not related to Gary Stone), claims that the addition of a six-speed transmission is the best single modification you can make to a 944 Turbo.


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