The B2K Callaway Corvettes were engineering marvels when the Tune-Ported torque monsters first hit the streets. Callaway drove home that fact with the tagline, “Powerfully Engineered Automobiles.” The cars were highly-capable of holding their own against the best of the day. They have also become highly-prized items for collectors of performance vehicles.

This C4 has undergone a surprising amount of modification since it left the factory, starting with an upgrade to B2K status by Callaway. The next chapter in this C4’s book of mods came through an extensive list of suppliers. Through it all, it retains most of its stock appearance. All images courtesy of Chris Jacobs.

As valuable as they are, Reeves Callaway and company built these cars to be driven, and that’s exactly what this particular 1987 B2K Corvette was doing when its engine went south. The car’s owner, Harold Chapman owns Customs And Hot Rods of Andice, Texas. He knew after almost three decades, there was — technologically — a lot of room for improvement under the hood, even if there wasn’t much actual room under that low-slung hood to make it happen.

Boost made the B2k the powerhouse it was back in the day, and it still has an amazing effect on a car’s performance. Rather than go the original twin-turbo route, Harold and the CHRoA team had a perfectly good Chevrolet Performance LS9 Connect and Cruise powertrain, including a 4L80e trans, sitting around the shop. They started fitting each of those supercharged, 638 horses under the hood and didn’t stop until they got them all stampeding together.

They knew the abuse that this car would be subjected to, so they set out to update the cooling system all around. For that, a half-dozen fans help keep this C4 cool. One pusher fan and four additional units direct air through the C&R Racing radiator — originally designed for the C7R — and custom-fitted it to the C4. One other air-mover helps cool the transmission with a diff-mounted cooler out back.

Beyond Boost

Few may remember how the Cross-Fire-equipped C4 Corvette’s handling turned the world on its ear with one-G-plus turning. Even so, the world has moved on so far as suspension improvements since the C4 Corvettes were introduced, and if this square-bodied C4 was going to make the most of that LS9’s power, it would need to be updated as well.

Harold owns the car, I’m just the lucky guy who gets to beat the crap out of it! – Chris Jacobs

That’s why Harold turned to the folks at RideTech. There, Tom Mcbride and the RideTech Engineering Team created a custom cradle assembly featuring a 9-inch center section and Dynotech Driveshafts completing the width of the custom IRS system. A full complement of RideTech three-way adjustable shocks and R-Joints allow for needed movement while keeping unwanted motion at bay.

A set of 18×11 (front) and 18×12 (rear) Forgeline one-piece, forged monoblock GS1R wheels finished in Brushed Bronze are wrapped in BFGoodrich Rival S tires. Wilwood brakes fill in the extra opening inside each wheel and help bring the C4 down from warp speed to turning speed. With such an aggressive chassis, you can imagine that this car was built to be driven. More so now, than ever!

Howard and company installed 1996 Grand Sport flares to help cover the 335-sized BFGs out-back.

Amazingly, the car only has about 14,000 miles on the clock, but that is changing rapidly, thanks to Harold’s friend, Chris Jacobs. That name may ring a bell with autocross enthusiasts, and yes, THAT Chris Jacobs. He met Harold and his supercharged C4 at a Goodguys’ event in Des Moines, Iowa, in 2009. Chris started helping him with driving in 2015 with his 1968 Corvette and began driving this C4 in 2018. Harold was struggling to tame the twisty ways of the C4 and Chris, a long-time Corvette enthusiast, lent a hand, and his driving gloves, to help sort it out.

Chris drives the car at many autocross events around the country. He is currently enjoying driving the car around his home town until the events start back up.

For the past two years, the duo has been autocrossing the C4 at various events. To make the car more track-capable, and to allow Chris to fit top-to-bottom in the Corvette, a set of NRG race seats and a quick-release wheel hub were added. Additionally, even though the factory “Vetari”  dash still works fine, a RacePak IQ3 digital dash info-system lets them know exactly what is going on during a run. The car has won multiple Goodguys autocross events in the Street Machine class and has been a class leader.

A Mean Street Machine

While this C4 is built to cut an apex with the best of them, it is also adding street miles to that factory odometer. Chris has been using the C4 as his “summer loaner” and admits, “Harold owns the car, I’m just the lucky guy who gets to beat the crap out of it”!

Chris is honest, admitting the feeling isn’t mutual. Seeing how hard he works the Corvette on the autocross track, he says it’s amazing how pliable the car is to drive on the street. Ground clearance has been a non-issue, even with the 2-inch primary headers and 3-inch tubing feeding into a Stainless Works C4 Corvette muffler. It even has the original BOSE stereo system and A/C to help keep its occupants cozy and entertained.

Even with the chassis turned up to eleven, the car still handles the highway quite well in its go-fast configuration. Chris explained the car is “set up so you can drive it,” he says. “There is like two degrees of camber in the front and one degree in the rear and the toe is pretty neutral,” Chris reports that with enough autocrossing, the tires wear pretty evenly, striking a balance between track handling and roadworthiness.

When it comes time for competition, they may adjust the three-way shocks’ compression and rebound accordingly, but that’s about it. Overall, with everything sorted, the car has become a REALLY great handling car! Even with 604 horsepower to the wheels, the car is quite drivable; but just squeeze on the throttle a little too hard, and it’ll annihilate the tires at just about any speed.

For now, and until groups of ten or more can safely congregate at the track, Chris will be enjoying his friend’s super-powered C4 on daily drives and occasional speed blasts. It’ll give him a chance to really nit-pick the car’s manners to ensure it’s as capable on the highway as it is the speedway. He’s already proven its speed worthiness, now it’s time to enjoy the car in the stop-and-go world.