Jim Smart
May 1, 2008
Photos By: William Harvey

Some purists might view this GT350 as sacrilegious-a twin Paxton restomod fastback sporting screaming small-block power well beyond anything Mr. Shelby envisioned 42 years ago. However, this is a GT350 that takes Carroll's vision a step further-a Shelby Mustang rocket hell-bent on challenging one's driving skills. It demonstrates that rewards are there for those bold enough to go where few Shelby enthusiasts have ever gone before. The logic is, you should never modify a historic artifact like a Shelby GT350.

Dave Heald broke all the rules-and wrote a few of his own.

Rule 1: It's OK to modify a Shelby Mustang if modifications can be reversed.
Rule 2: You only go around once in life (OK, so we swiped it from a classic beer commercial); make the most of it.
Rule 3: Apologize to no one; have fun.
Rule 4: Fill it up with 110-octane racing gas.
Rule 5: Please fasten your seatbelts.

When Dave found his GT350, it was complete but in pieces seeking a buyer. It was a numbers-matching Shelby ride that still had its original 289 Hi-Po engine, Top Loader four-speed, and 9-inch rearend with Detroit Locker. Even the original steering wheel was still there. It was an unbeatable deal at a time when good finds were thought to be all gone.

Dave wanted a high-end concours restoration; then he'd put the Shelby away for safekeeping as a good investment. He understood the value of putting the car away for a rainy day, but the desire to drive and enjoy the car overwhelmed him. What to do? First, he honored the car with a 100-point restoration by Paul's Automotive Engineering in Cincinnati, Ohio, based on Paul's 20-year reputation as a high-end Shelby restorer. If you study the details closely, Paul's did a magnificent job. Not one detail was overlooked.

Dave and Paul's Automotive decided to keep modifications hidden to where the car's original character wouldn't be lost. Externally, buried beneath Paxton power, this looks like a 289 High Performance V-8-right down to the open-letter Cobra valve covers and 8V induction. Because Dave didn't want to risk the Shelby's original matching-number 289 block and heads, he elected to build a new 363ci small-block from scratch. That called for a fresh aluminum block from Ford Racing Performance Parts and a Dominator stroker kit from Coast High Performance. Wanting to stuff as much displacement as he could into his blown small-block, Dave opted for Ross 4.125-inch custom pistons with a dish, yielding 9.5:1 compression. Ross slugs ride on Probe 4340 H-beam rods and a 4340 steel crank, all of it dynamic-balanced at Paul's Automotive for smoothness.

When you build a stroker small-block like this one, you can't think of it as a 289 or 302 anymore; you have to treat it like a 351. That's why Dave went with ported Trick Flow Twisted Wedge heads with 2.02/1.60-inch Ferrea stainless valves along with an aggressive Trick Flow hydraulic roller camshaft. It takes a lot of know-how to package the twin superchargers. Each 450-cfm Holley 1850 carburetor has its own period Paxton supercharger, which calls for precision tuning and a lot of common sense. You may look at the Autolite dual-point distributor and scratch your head, but don't. Paul upgraded the Autolite sparker with a Pertronix Ignitor II ignition upgrade, which gives Dave all the benefits of modern electronic ignition while keeping the OEM distributor. You've got to love the car's engine room because it's such a well-integrated combination of nostalgia and current technology. And aside from the hidden Pertronix Ignitor, it sports speed-performance elements from the '60s.

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Dave put his Shelby's Top Loader four-speed away for safekeeping, too. In the tunnel is a Tremec T-5 five-speed transmission built to take the twist of a 540hp small-block by G-Force. This allows Dave to lay down rubber and accelerate smartly while slipping into Overdrive cogs at highway speeds. Because Shelby had brute performance in mind 42 years ago, Dave didn't have to do anything to the 3.89-geared Detroit Locker but freshen it up with gaskets, bearings, and seals. However, because he wanted greater levels of reliability, he had Paul's upgrade the diff with a Strange carrier and Torque Sensing 31-spline differential. In Overdrive, 3.89 gears keep open-road revs modest, and when it's time to rock, all Dave has to do is leave Overdrive and let those Paxtons go to work.

Although Dave's GT350 packs a lot of power underhood, it remains the essential Shelby elsewhere. Paul's Automotive did this car justice by blueprinting the suspension system, including the red Koni shocks. On the ground are period 15x7-inch Shelby Cragars wrapped in BFGoodrich Comp T/A radials for exceptional handling. Kelsey-Hayes front disc brakes deliver the same kind of stopping power they were designed for four decades ago. When you study this Shelby's underpinnings, it's easy to get into details-all those things that make a concours restoration exceptional.

When you slide inside, it's a trip back to 1966, void of the amenities we've grown so used to in the years since. You won't find a 1,000-watt stereo or a "boom-boom" subwoofer to help you forget what's underhood. There's no satellite navigation, video screen, or six-disc CD changer, either. This is about respecting a classic Shelby's legacy, with a splash of salsa beneath the bonnet just for fun [If you call 540 hp at the tire a "splash!"-Ed.].

Although some might consider Dave's approach to an unmolested Shelby unconventional, this man has never forgotten Carroll's legacy, nor what it will always mean for his followers. Meanwhile, Dave's going to have fun, treasure the experience, and go where most fear to tread.

The Details
'66 Shelby GT350 Fastback
Owner: Dave Heald

Engine
363.5ci displacement (302-based block)
4.125-inch bore, 3.400-inch stroke
Ford Racing Performance Parts aluminum block
Probe 4340 steel crankshaft
Probe 4340 H-beam rods (5.400 inches)
Ross custom forged pistons
Trick Flow heads with complete port work by
Paul's Automotive
2.02/1.60-inch Ferrea stainless valves
Trick Flow Stage III hydraulic roller special
(0.575/0.595-inch lift, 298/310 duration)
1.6:1 Trick Flow roller rockers
Dual Trick Flow valvesprings
Twin Holley 450-cfm carburetors
Twin Paxton superchargers
Autolite dual-point distributor with
Pertronix Ignitor II conversion
MSD-6 BTM ignition
Reproduction Autolite ignition wires
Open-letter Cobra valve covers
Heavy-duty battery cables
Two-row aluminum radiator
High-flow aluminum water pump
540 rwhp
470.4 lb-ft of torque

Transmission
G-Force-modified Tremec T-5 five-speed

Rearend
9-inch
3.89 gears
Strange aluminum carrier
Torque Sensing 31-spline differential

Exhaust
P.A.E. stainless 1 5/8-inch headers
2 1/2-inch stainless steel dual exhaust
MagnaFlow stainless mufflers

Suspension
Front: Blueprinted stock coil springs, reinforced upper and lower control arms, Koni shocks
Rear: Mid-eye five-leaf springs, Koni shocks, underride traction bars

Brakes
Front: Upgraded Kelsey-Hayes four-piston 12-inch disc
Rear: Full-size Ford 11x2 1/4-inch drum
Dual braking system added for safety

Wheels
Front: Custom Shelby-Cragar 15x7 mag wheels
Rear: Custom Shelby-Cragar 15x7 mag wheels (factory wheels were 15x6)

Tires
Front: BFGoodrich Comp T/A, P255/60R15
Rear: BFGoodrich Comp T/A, P255/60R15

Interior
Stock GT350, Hurst T-5 shifter, Shelby Eight-Grand tachometer

Exterior
Sapphire Blue by Paul's Automotive, Cincinnati, Ohio