At some point, Hight decided the standard 3.42 gears were too tall; he wanted something more aggressive. After some consultation with Mosello, he went with a 4.10:1 final-drive ratio. As with the intake, this was not an off-the-shelf part. “To make this work,” explains Mosello, “we had to completely replace the Z06 diff with a new housing and special side covers and have the 4.10 ring-and-pinion gears specially re-splined and modified to work with the Z06’s larger output shaft.” While they were at it, the shop installed beefier 300-mm billet axles.
With a stouter rear end in place, the temptation to add more power proved irresistible. Hight decided to have a more aggressive cam installed —specifically, an LG Motorsports G7X3 with a custom grind. Adding a radical bump stick also meant that the engine internals needed to be upgraded, so in went heavy-duty dual springs, titanium retainers and locks, a heavy-duty timing chain, hardened pushrods and a custom ATI underdrive pulley. The stock Z06 rocker arms were also replaced with Harland Sharp units, featuring larger, more reliable trunion bearings.
With these mods in place, the buildup of heat became an issue. Hight wanted to be able to use the car whenever he desired, and New York City can be a hot place during the summer months, so an extra-large DeWitts heavy-duty radiator was fitted.
Underneath, the suspension was also tweaked. The original Z06 transverse leaf springs and shocks were replaced with a set of Pfadt coilovers. This lowered the car, giving it a more aggressive stance, while also allowing the rear wheels to be sprung more independently. To reduce body roll, stiffer GM T1 anti-roll bars were installed. A set of Hawk pads gave the brakes a bit more bite.
But wait, there’s more! Though the Corvette had nearly 550 horsepower at the rear wheels, Hight still wanted additional ponies under the hood. Mosello recalls the day Hight showed up at the shop with a Vortech supercharger in hand. Mosello asked, “Sonny, are you sure about this?” “Hell yes,” was the response, so the blower went in. As with the rest of the car, this was no bolt-on affair. Mosello ended up customizing the plumbing to permit maximum airflow to the intercooler. The fuel injectors were sent to Georgia-based Fuel Injector Connection for some modifications, which would be critical to insuring an adequate fuel supply. The fueling system was further optimized with the installation of a fully ported FAST 102 intake manifold and a Warlbro fuel pump. To give the engine bay a bit of bling, a pair of Katech aluminum valve covers were fitted, as was Katech’s coil-relocation kit.
Hight’s Z06 now produced a stout 700+ rear-wheel horsepower. It also generated a lot of heat. To help remedy this, the stock hood was replaced by a vented carbon-fiber hood from Motor City.
By now, you’re probably wondering if this project will ever end. Probably not. A Katech ZR1-style aluminum flywheel, a GM ZR1 dual-disc clutch and a ZR1 clutch slave cylinder modified with a remote bleeder were recently installed. A B&M shifter was fitted at the same time. The clutch can now handle upward of 900 rear-wheel horses; perhaps another hint of things to come? The Borla exhaust was replaced with an Akrapovic Evolution system, which is crafted for the most part from titanium, but sports carbon-fiber tips. While it’s hard to say how much horsepower this exhaust system saves, it weighs 25 pounds less than stock.
What’s next? The Z06’s interior is still bone stock save for some extra gauges, so it’s a safe bet that some changes are in store for the cockpit. There are a few additional tweaks to the fuel system being planned, but more horsepower is not a priority for Hight at the moment. He is satisfied for now—until the Corvette bug bites again.