Right around the time the Buffalo Bills were appearing in a record four consecutive Super Bowls, Chevrolet introduced the LT1 V-8. Not coincidentally, the two events shared uncanny similarities. Despite a devastating, no-huddle offense that routinely put seven points on the scoreboard in less than a minute, the Bills of the early '90s were known for never once bringing home the Vince Lombardi trophy. 'Tis a harsh fate for a team that was, in reality, second best in the NFL during that stretch. Likewise, from a technical standpoint, the LT1 is arguably the second-best small-block Chevy ever built. However, due to the overwhelming feats of its successor - the LS1 - it's often treated as a lame duck in the history of Chevy small-blocks. As to how history remembers their efforts, the Bills are just screwed, but bringing some hard-earned respect to the LT1 camp is Ben Moore and his '94 Camaro Z28.
Compared to the LS1, does the LT1 really suck that much? Sufficient evidence certainly exists that suggests so, but that isn't so much a sucker punch to the LT1's ribs as it is a testament to the progress of technology. After all, we're comparing the product of mid-'90s engineering to a design that traces its roots back to the mid-'50s. Nevertheless, the modern tweaks engineers infused into the old-school Mouse motor to create the LT1 firmly fortified its status as the pinnacle of traditional small-block Chevys. Reverse-flow cooling, which routed coolant into the heads before the block, allowed for an astounding 10.4:1 compression ratio on pump gas. Instead of relying on the archaic, time-based ignition systems of the day, the LT1's Opti-Spark system used optical sensors to precisely identify the angle of the crankshaft within 1-degree increments, affording individual cylinder timing control and a more aggressive spark curve. With Vortec-style aluminum cylinder heads, poked and stroked LT1s can easily crack 550 hp with factory castings.
Unfortunately, the same features that distanced the LT1 from its lesser forebears resulted in enough parts incompatibility with Gen I small-blocks to limit its ultimate potential. The unique water jackets needed to accommodate the reverse-flow cooling system limit maximum overbore to about .030 inch, making LT1s that eclipse the 400ci mark extremely rare. Likewise, LT1-specific water passages severely limit aftermarket cylinder head availability and worse yet, there's no such thing as an aftermarket LT1 block. Even with tuning software, the factory computer won't rev much past 7,000 rpm, and the brick-shaped intake manifold -designed more for hood clearance than a broad powerband - presents a severe bottleneck beyond 500 hp. As with the block, no one ever bothered to design an aftermarket intake manifold for the LT1.
Suddenly, the view from second place doesn't look so good. But instead of ditching the LT1 like most hard-core F-body enthusiasts, Ben Moore built a car that can handily stomp most LS1s. Clearing the aforementioned hurdles required a combination of ingenuity and compromise. The first compromise was settling on a modest displacement of 396 ci, achieved by combining a .030-inch overbore with a 3.875-inch stroke. Stuck with the factory block, Ben used splayed four-bolt main caps to make the most of a less-than-ideal foundation for building power. Typically, sliding in a big, nasty cam and zinging out the revs can compensate for a shortage of cubes, but there's that rev-challenged stock PCM to deal with, and Ben didn't want to spend the bucks for a stand-alone EFI system. That put an even greater emphasis on the selection of top-end components, so the cylinder heads of choice were 210cc units from Air Flow Research. They have been rubbed on by Meaux Racing Heads (Abbeville, Louisiana) to flow 289 cfm on the intake side and 230 on the exhaust. Moreover, to work around the limitations of the stock PCM, Ben spec'd out a custom 259/267-at-0.050 solid-lifter cam that peaks at 6,800 rpm.
While the selection of parts has been carefully thought out, nothing really stands out as innovative. However, this is where the story gets much more interesting. Since no aftermarket intake manifolds exist, Ben made his own by adapting a Brodix HV1 single-plane unit to fit. This was far from simple and involved welding the water passages shut (the LT1 intake is dry) then redrilling the bolt holes to match the angle on the LT1 heads. The manifold was then shipped off to Force Fuel Injection (Miami) to have the injector bosses installed. Reichart Racing built a custom, 90-degree elbow to fit the Dominator-style flange on one end and an Arizona Speed & Marine monoblade throttle-body on the other. To route fresh air into the motor, Ben took a 4-inch piece of aluminum pipe, massaged it into an oval to fit the throttle-body, then sectioned and welded it all up. The pipe then Y's to the foglight openings, and Ben says the ram-air effect is good for an honest 2 mph in the quarter-mile. In an effort to scratch and claw for those last few percentage points of power, a Moroso vacuum pump mounted with custom brackets improves ring seal and oil control and a Meziere electric water pump reduces parasitic drag on the motor. A custom dual exhaust routes gases into an X-pipe off the headers then dumps them in front of the rearend.
The final product from all this scheming is 456 hp and 367 lb-ft on the chassis dyno: about as good as it gets for a naturally aspirated LT1. However, that's still not enough to propel a porky fourth-gen into the single-digit realm, and it didn't. On its first track outing with the new engine combo, the Camaro went 11.0 at 125 mph. Although Ben's original goal was to run 10.50s, that first trip to the track made him realize there's more potential in the package than he anticipated. Content with the horsepower at his disposal and convinced the engine combo was maxed out, he shifted his attention to suspension setup and reducing the car's 3,417 pounds of mass. In went a BMR tubular K-member, A-arms, rear trailing arms, and a Panhard rod. QA1 adjustable shocks help transfer weight, and a custom torque arm puts the power down.
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