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1973 Mercury Comet -The Quest For 10s

A Mad Scientist Twisting Small Block Ford Dr. Setzer

Photography by , , John Baechtel

'Mix one part rockabilly with an equal helping of gearhead fabricator, stir vigorously, and what pours out is Tom Habrzyk. The guy looks like Brian Setzer but plays the small-block Ford, twisting them till they scream. A Polish exchange student who barely spoke English 10 years ago, he's going to school while spinning wrenches for pennies, driving a primered '58 Fairlane every day, and setting motorcycle land speed records at Bonneville and El Mirage. It's as American as baseball, hot dogs, apple pie, and a dire need for a 10-second '73 Mercury Comet. And not easy 10s, but normally aspirated with a tiny 306ci Ford on pump gas.

Tom turns wrenches at Westech Performance Group, which readers will recognize as one of this magazine's favorite dyno haunts. Tom runs the chassis dyno, but his job also gives him insider access to a SuperFlow engine dyno. That lets him quantify progress but doesn't make the construction any easier. Like most car crafters, Tom doesn't have a pile of money, and he works virtually every spare minute flogging his combination. That means he's able to share lots of information as we follow his quest, this month with the engine buildup, and next month with an in-car flog.

RootsThe whole deal began four years ago when Tom traded a clapped-out '86 Mitsubishi pickup for a Comet with a sick six. Since then he's done all the work on it himself including the paint and rollcage. The V-8 swap began with a $1,000 EFI 302 yanked from a '93 Ford Explorer with all the factory wiring, sensors, and distributorless ignition. Initially the electronics were set aside as Tom gave the Explorer heads a mild port job, stabbed a Comp Cams 266 Extreme Energy cam, and topped the 302 with a Victor Jr. and an 850 Demon to make 400 hp. It only made 388 hp with an Edelbrock RPM Air Gap dual-plane, but that manifold had better low-end and led to the combo's best e.t.: 12.80.

Tom was hooked, and wanted another 100 hp. His strategy included fuel injection, but with an aftermarket controller to easily tune the fuel and spark curves. The short-block was also rebuilt, dumping the stock rods in favor of stronger Scat 4340 I-beams with 31/48-inch bolts and topping them with SRP's budget forged flattop pistons (PN 138734). Tom had the cast crank pins spun 0.020 inch undersized. The block was decked, then the cylinders were torque-plate honed to seal the 11/416-inch Federal-Mogul rings and standard-tension oil rings. Tom tried low-tension oil rings, but oil seemed to be getting into the chambers at part-throttle, so he went back to standard-tension. The 306-incher is buttoned up with Speed-Pro bearings, Fel-Pro gaskets, and an 8-quart Milodon pan.

Heads FirstWith a 500hp goal, he knew it was time to invest in cylinder heads. Cheaping out on heads only mellows the results, so Tom stepped up for a set of Airflow Research 185 CNC heads with 2.02/1.60-inch valves. Because it's troublesome to generate high compression with small-cube engines, Tom had AFR angle-mill the heads for 51cc chambers (58, 61, or 69 cc's are standard). Combined with an amazing 0.015-inch-positive piston deck height (the pistons stick out of the bores) and thin 0.039-inch-thick Fel-Pro head gaskets (PN 1011-2), Tom was shooting for the tightest quench area and smallest combustion space he could create. This resulted in an incredibly tight piston-to-head clearance. In theory he's got around 0.024 inch; piston rock trims the piston clearance to far below 0.020 inch, but so far Tom has had no problems with the pistons smacking the heads. Chalk this up to decent 1.7:1 rod-length-to-stroke ratio and a short stroke, reducing both piston rock and piston speed, respectively.

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