911 Shape Shifter

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  • ALMS 2010: Porsche battles for victory
  • Glöckler: A Restored one-off
  • GT3 Cup wins class at Pikes Peak
  • Premiere production 914-6
  • GT3 R Hybrid: It has boost, but no turbo
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  • Stock Boxster S vs. Boxster Spec Racer
  • Mid-engine Buyer's Guide
  • Green Porsche: Cayenne S Hybrid driven
  • Targa California: big thrills, low frills
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Fortunately for Gagen, his wife Yvonne showed her support early on by accompanying him to the races and giving input on aesthetic decisions. One problem they discovered early on was that making molds to replicate the custom body parts would be expensive, and if Mike went off course before that happened, rebuilding the one-of-a-kind panels would be just as costly. Another consideration was the rear flares, which were heavy and contoured for 27-inch tall tires. Gagen had decided to return to a 25.5-inch race slick, so these would need to be reshaped again. That was the last straw, and his “RSR+” concept was abandoned after just one year to make way for 993-style bodywork.

Wanting more performance than the 3.2 could give, Gagen decided it was time for an engine upgrade, too. After locating a 1995 993 engine, he asked an old VW hot rod buddy named Victor Ofner rebuild it. Now retired, Ofner worked in Porsche’s race shops building 962 motors after completing his mechanic’s training in Germany. He would later become crew chief at SoCal’s Alan Johnson Racing.

Built to custom specs, Gagen’s motor is impressive: 3.6 liters with Supercup cams, 964-style cam gears, RSR solid rockers, and Carrillo rods. Before assembly, the crankcase was boat-tailed and some intake blending was combined with stock-size valves. The piston tops and the valve-face surfaces received heat-barrier treatments, while the piston sides received a Teflon treatment and the valve springs and retainers were cryogenically treated. The motor has two Motronic chips, one for 91 octane and the other for 100. Claimed peak rear wheel horsepower is a hefty 306 at 6600 rpm, and torque is reportedly 264 lb-ft at 5500 rpm using 92-octane fuel.

The 915 gearbox rebuild that accompanied the new motor features five custom gears, including a tall first and short ratios for second through fifth. Gear spacing drops 1000 rpm with each shift at 7000 rpm. The box has many Wevo parts, which includes the extra tall shifter, shift gate, bearing bridle, and 8:31 ring-and-pinion setup. A dedicated transmission oil cooler and filter, 60/40 limited-slip differential, and McKenzie-blueprinted 911 Turbo CV joints were added before the transmission was installed ahead of a lightweight flywheel and Centerforce clutch.

By 2005, the time had finally come for version three. Starting in 2003, Mike’s 911 had undergone many changes, including a move back to taller tire sidewalls. Attendant suspension surgery included new spring-plate bungs welded in and triangulated two inches above the torsion-bar tube. Along with adjustable control-arm mounts, this change allowed for proper geometry with a lowered ride height and huge tires.

“With a 27.2-inch diameter slick, you lose suspension geometry,” says Gagen. “So raising the pivots permitted us to have tall rear slicks and a very low ride height.” At this point, the 911 had ERP 935-style front and rear spherical-bushed coil-overs, Smart Racing Products anti-roll bars and JRZ front and rear shocks, all of which were dialed in at Willow Springs Raceway. The old roll cage was tossed in favor of a custom full cage from Auto Power, which was attached at the revised suspension pick-up points and the tubular rear sub-frame using 2×3×12-inch sleeves.

The interior had not escaped Gagen’s attention. Kirkey race seats were installed along with a cool suit/helmet blower that’s located between the passenger’s feet. The Motronic engine-management brain, Optima dry-cell battery, and air jacks were mounted in the back of the interior, under aluminum paneling designed by Jim Copp. There’s more than a little “race car” left in this 911’s cabin. Peering in, Gagen says “See the primer paint under the steering coupler? I had the firewall roof raised two inches above the gas pedal for my size-14 Simpson racing shoe.”

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