Tom and his brother are lifelong gearheads, so this Chevelle is the natural extension of a string of performance cars that dates back to a '68 Nova Tom bought when he was 14, which eventually appeared in a couple of magazines back in the mid-'80s. After a stint with drag boats, which is almost a requirement when you live in the Land of Lakes, Tom decided to build a triple-threat street car. "I wanted to build something that I could do everything with-drive it on the street, show it, and drag race it." That may not sound like much of a challenge, but for those who have attempted it, building a show car that can also run in the 8's is no easy feat. Look closely and there is virtually no part of this Chevelle that hasn't been rubbed on, cut, welded, or alloyed.
The effort was built around a complete round-tube chassis constructed by Greek's Pro Shop in Spring Lake Park, Minnesota. The chassis is NHRA-certified to run 8.50s, but Tom has much loftier aspirations. "I could have built the chassis to be legal for 7.50s, but that would have required a Funny Car 'cage. They're too hard to get in and out of for a street car, so we used the standard 'cage instead." A 7.50-second e.t. may sound a bit pretentious until you realize that in-your-face 632ci Rat, with its split King Demons and multiple stages of nitrous, is not just for show. This is the real deal.
If horsepower is king in the land of musclecars, then Tom's Chevelle is no mere usurper to the throne. The parts rundown for this motor reads like a shopping list for a Pro Mod racer. Let's start with the all-aluminum block for this 632. While Dart or Donovan usually head the list, Tom went with an Arias foundation called the New Century block, a newcomer that impressed Tom with its bracing, cross-bolted mains, and structural integrity. This 10.700-inch raised-deck block also raised the cam location, used a larger 60mm cam core, and spec'd 15:1 CP pistons for the short-block. "CP offers something like 13 options for custom ordering the pistons, and we took advantage of all of them," Tom says. Include a pair of CFE-ported 14-degree Dart Big Chief heads and a Jesel beltdrive and valvetrain along with 2.500-inch titanium intake valves, and the lunatic fringe moniker may seem inadequate.
Forget the all-show and no-go concerns, because he's already leaned on this engine pretty hard. "The motor's been up on the dyno three times already," Tom says. "We've tested all kinds of things like rocker ratios, heat ranges for the spark plugs, different weight oils, all kinds of stuff." At first, the power was, to use Tom's word, "disappointing,"so he bumped up the cam timing where the lift is just shy of 1 inch at 0.930 and the power now is a steam-generating 1,200 hp at 7,600 rpm making 930 lb-ft of torque at 5,800 rpm on a SuperFlow 902 dyno. Consider as well that there are also two stages of Wilson nitrous available that Tom has yet to trigger. "Right now the engine is really safe, and we'll start conservatively on the nitrous, but we can run up to 400 hp on the first stage and 250 on the second." We'll do the math for you: that puts this big Rat at 1,850 hp with both stages. And remember, Tom said he was being conservative.
Ironically, one of the most pedestrian of all production automatic transmissions is most often the trans of choice with high-powered cars like Tom's. His good friend and fellow drag racer Ron Flood at Cedar Machine, who did all the machine work on the engine, also assembled the Powerglide. "It's got all the good parts in it, too," Tom says, which only makes sense with near double-century-mark power numbers. This includes a Dedenbear case and a Hughes 9-inch converter that leads to a Ford 9-inch with a mild 4.11 gear set. With this much power, you don't need a lot of gear. The Greek's Pro Shop welded the all-chromoly round-tube chassis complete with a 14-point 'cage to give the drivetrain something to hang on and to help somehow manage all that horsepower. Morrison supplied most of the components for the suspension with help from a set of Afco aluminum coilover shocks.
All the madness happening under the hood tends to distract your eye from the subtle changes going on with the body. Even card-carrying Chevelle guys might overlook the mild roof slice, artfully executed by Central Avenue Auto Body. Once you look, you may also notice the missing roof driprail, the shaved emblems, and the flush door handles. What isn't hard to miss is the multicolored paint explosion that slides down the Chevelle's flanks.
All told, it took Tom and his cohorts 51/2 years to complete this amazing Chevelle. But this isn't the end of the story. He has several dragstrip adventures in the works for the coming year, and there's already a chassis dyno tuning session planned as well as many more street miles. Regardless of where this car goes, it's bound to attract a following. The lunatic fringe always do.
Who: Tom Johnson
What: '67 Chevrolet Chevelle
Where: Moundsview, Minnesota
Short-block: Let's start with the Arias all-aluminum block stuffed with 4.600-inch-bore CP forged 15:1 pistons, Total Seal Hellfire rings for the nitrous, a Howards forged-steel 4.500-inch crankshaft, GRP aluminum rods, and Federal-Mogul bearings displacing 632 ci. Tom also added ARP studs, copper head gaskets, and a complete five-stage Moroso dry-sump system with the tank located just ahead of the radiator. For oil, Tom uses Redline 5W-30.
Heads and valvetrain: If you're really serious about making horsepower, a set of Dart Big Chief 14-degree heads is a good place to start. Tom then had Carl Foltz's Detroit-area CFE Racing work its port magic, which pulled the intake flow up to around 530 cfm using 2.50/1.88 titanium valves, Isky valvesprings, and titanium retainers followed by a Jesel shaft rocker system using 1.9:1 intake and 1.8:1 exhaust rocker ratios. The Comp Cams mechanical roller is a larger 60mm core that spins on roller cam bearings. Cam timing is, like everything else in this engine, big at around 260-plus degrees at 0.050 with 0.930-inch lift.
Induction: This is the attention-getting part of the car. CFE also built the sheetmetal intake that locates four split King Demon carburetors relocated to sit directly over a pair of intake ports. Each two-barrel flows 600 cfm, making the total potential airflow something ridiculous like 2,400 cfm. Tom also added two stages of Wilson Nitrous Pro Flow nozzles in the intake to add 400 hp in the first stage and up to an additional 300 on the second stage. All this is fed by a MagnaFuel electric pump flowing VP C23 race gas through matching purple anodized MagnaFuel regulators. Tom also has two NOS controllers, one for each stage, as well as EGT probes in each cylinder.
Exhaust: Tom built his own stepped headers, starting with a set of 23/8-inch primary pipes that bump up to 21/2 inches that then lead to a pair of DynaTech merge 4-inch collectors. Because the car sits so low, Tom built his own exhaust using SpinTech mufflers and 23/4x5-inch-wide oval tubing. The exhausts exit through the rocker panels just ahead of the rear tires.
Transmission: The Powerglide uses virtually no original parts, relying on a custom blend of a billet input shaft, 10-disc clutch pack, and other pieces assembled by Ron Flood of Cedar Machine that Tom says is good to 2,500 hp. The Hughes 9-inch converter makes the fluid connection bolted to a Reactor billet flexplate and stalls at a conservative 4,000 rpm using a B&M trans cooler and a 4-inch-diameter Inland Empire driveshaft.
Rearend: The narrowed 9-inch mounts Richmond 4.11:1 Pro Series gears mounted in an aluminum Strange centersection spinning gun-drilled 40-spline Strange axles.
Chassis: If you're serious about going fast, you need a chassis that will back it up. Tom didn't scrimp here either, using Greek's Pro Shop in nearby Spring Lake, Minnesota, to construct the all chromoly round-tube chassis complete with Art Morrison front control arms connected to Morrison spindles and rack-and-pinion steering system. In the rear, you'll find a custom four-link rear suspension with Afco billet coilover shocks to help put the power down.
Wheels/Tires: Minimizing the rotating weight means a set of Weld 15x4-inch Draglite wheels and M/T skinnies up front with 15x14-inch Draglites in the rear mounted with a pair of Mickey Thompson 32x18-15 slicks.
Safety: In the trunk is a complete 15-gallon Jaz fuel cell not far from the Stroud parachute. The interior is sprinkled with a Stroud window net and five-point harness assembly.
Body and paint: Tom had to point out much of the work performed by Central Avenue Auto Body in Minneapolis right down to the 2-inch trim at the front A-pillar and the 1-inch mill job performed at the rear to rake the roof. The drill rails were also shaved, and Tom installed the Percy's Speed Glass flush with the front and rear window levels. Tom retained the stock vent wings to allow in fresh air since the side Speed Glass windows are fixed in place, but he did remove all the emblems, adding flush-mounted Buick Regal door handles. Kenny Zupata spent days custom-mixing the base silver that has pearl, while the blue began life as a Mitsubishi color before they hit it with several pearl concoctions. There's even a little purple added in that was originally a Honda motorcycle color before it too became infused with pearl accents.
Interior: The dash is completely custom sporting an array of Auto Meter gauges too numerous to list. Clint Foner of Big Lake, Minnesota, performed the enormous task of wiring this beast, working around the Kirkey aluminum seats, the 14-point 'cage, the Colorado Custom steering wheel, the Biondo shifter, and the pair of Wilson nitrous bottles behind the passenger seat.
Performance: Engine dyno'd at 1,200 hp with another 700 hp available with nitrous. Tom is shooting for any number in the quarter-mile that starts with a 7.