Sleight of Hand
What you see is not what you get with this stock appearing Hemi GTX
Story by Chris Endres 2003
Got a quick street machine? Like to take it out on cruise night and pick on stock musclecars? You might want to think twice before messing with Joel Nystrom's innocent-looking 1967 Hemi GTX. Though it appears suitable for feature in a chalk-mark-and-grease-pencil periodical like Musclecar Review, this GTX is one of the fastest cars competing in the hot new factory-appearing drag race craze. Would you believe this car capable of running deep into the elevens, just as it sits? No slicks, no DOTs, no drag radials. Hell, the car hasn't even got headers. So how does a guy get a car like this to run so quick? Attention to detail? Technique? Magic?
Perhaps the most obvious answer is power, and lots of it. Cloaked under the guise of a stock air cleaner and valve covers is a 484ci short block, based on a '66 Hemi cylinder case. Inside, the rotating assembly consists of a Mopar Performance 4.15-inch stroke crankshaft, Wiseco 11.8:1 forged pistons, Childs & Albert rings, Manley Sportsmaster connecting rods and Federal-Mogul bearings. Engine magician Chuck Lofgren performed all necessary machine work to the block and components, and Nystrom completed the final assembly. Nystrom also fabriicated a custom, stock-appearing, 8-quart oil pan. A stock 2x4 intake manifold was relieved of its plenum dividers and mounts two original Carter AFBs. Fuel delivery is provided by a stock mechanical pump, which is supplemented by a Holley 90-gph electric unit. Lying concealed is an MSD 6-AL ignition box, which in turn is triggered by the factory dual point distributor (with one set of points removed). "I added the MSD box mainly to make use of its rev limiter function," Nystrom said.
The fabled Hemi heads were left in the skilled hands of cylinder head shaman Glen Knowlton for machine work and porting. Manley stainless steel valves (2.25-inches intake, 1.94-inches exhaust) and Landy roller rockers were added to work in conjunction with the solid roller cam of undisclosed specifications. With the engine assembled and dropped in place, extrude-honed exhaust manifolds were added, along with a Dr. Gas X-pipe, a TTI mandrel-bent 2.5-inch exhaust system, and Dynomax Ultra-Flo stainless steel mufflers. Run on a chassis dyno, the big Hemi produced an unassailable 550hp at the rear wheels. What is most surprising about this is just how docile the car is at idle and when puttering around at cruising speeds. Crack the throttle, though, and you'll have little choice but to fall under the spell of the Hemi.
Less obvious is the plethora of unseen tricks populating the car, all made in the name of stealth and quick ETs. The gear set in the original four-speed was sent to Liberty for refurbishment and re-installed in the freshened crashbox by the owner. He also installed a McLeod 800-series clutch with a 14-pound aluminum flywheel. The original Dana 60 rearend now contains 4.10 gears and a pair of Strange Engineering S/T axles. Notable suspension modifications include poly bushings in the rear springs, an adjustable pinion snubber, and Competition Engineering shocks, 90/10 in front and Mopar Performance 50/50 in the rear.
Though most of these mods are pretty much standard fare in the Factory Appearing Drag ranks, one area where Nystrom has bucked the trend is in his choice of rolling stock. While many of his competitors are going the route of stamped steel wheels and hubcaps in the name of reduced weight, the green machine sports factory Magnum 500 wheels. Mounted on the factory chromies are reproduction Firestone F70-14 redline tires that serve duty on both street and strip. "I've played with tire pressures a lot," he added. "Most guys who run small bias ply tires report best traction with 40 psi or more. That didn't work too well for me; 32 psi seemed to provide the best 60-foot times. I've also experimented with many different traction compounds for the tires, and found that Formula V works the best. I apply it to the tread with a paint roller three times a day for three days, then allow it to dry for at least 48 hours before use. It's not a miracle that turns bias-plies into slicks, but it does help."
Very much the hands-on type, Nystrom is proud to say that he has done nearly all of the work on the car himself, including the transmission and rearend assembly. To wit: "I cut the guts out of an authentic (read: expensive) re-pop battery and hid a 15-pound Dyna-Batt dry cell inside. That saved 37 pounds off the front end of the car. At the other end, I filled a spare tire with water and install it when traction is low. This helps a bit off the line, but hurts the top end." Inside is a completely original black interior, looking remarkably fresh for its age. Even the shifter is stock. Or is it? Nystrom confesses: "I modified the stock handle and mounted it to a Hurst Competition Plus shifter."
So which modification has worked best? "I don't think any one mod really dominates. It has just been a lot of little things. Well, I suppose the roller cam really helped. That combined with the extrude-honed manifolds added 60hp. The intake manifold modification added another 25 horses, but it may have actually hurt overall performance. It forces me to rev it higher to launch without bogging. If the track is slippery, that is more likely to cause tire spin. Of course, when the traction is there, it helps," he said. All told, the combination works very well as the car's best pass ever is 11.27 at 127 mph. "The more seat time I get, the faster it runs. Learning to drive a 650hp car on 6-inch wide poly-glass tires takes practice; it's a lot different than running slicks!"
Like any good illusionist, Joel Nystrom is a master of diversion. With nothing up his sleeve but a Hemi, he draws you in and distracts you with a mellow exhaust note and a stock-appearing resto look. But given half a chance, he will be busy making your mean machine disappear... In his review mirror!
WHAT IS FAST?
FAST is the acronym for Factory Appearing Stock Tire drag racing. The FAST idea is to "look stock, sound stock and run fast, the way musclecars should." FAST is designed to allow competition between production musclecars built from 1955 to 1974. Banned however, are factory lightweight cars built for sanctioned drag racing, such as the Super Stock cars. Also illegal are those built or modified by dealerships of the day, such as the Yenko or Baldwin/Motion creations. In other words, the car year, make, model, body style and engine combination must all have been produced and available to the general public. In order to compete, cars must be equipped with "a minimum of four-barrel carburetion, dual exhaust, and other factory installed equipment that promotes a high-performance image." The cool part is that any modification that leaves the car looking and sounding stock is fair game.
This car was sucsessfull in FAST racing, setting a new MPH record at 5 consecutive events, #1 qualifier at it's first FAST event, 6 final rounds appearances and one win. It was also featured in Popular Hot rodding and Mopar Muscle magazines, as well as sevral apperances in other magazines, even Suoer Chevy Mag!
The car is now retired from F.A.S.T. racing, since I built a clone that I can thrash on even harder with no concerns of preservation
In car 1/4 mile pass: http://youtu.be/uu94rcdWFyM
1/4 mile pass from the rear: http://youtu.be/snKfkP8nqg4