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1967 Chevy Chevelle - Lunatic Fringe

Tom Johnson's maniacal, 632ci, 1,200hp '67 Chevelle - we call this the Crazy Chevelle.

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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.

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