#TBT: A budget CRX racer built with a Chevy V8 and a Mustang chassis | Articles

Hatching the Plan

The Crabill team decided that if they were going to enter the 2004 event, it wasn’t going to be with a bolt-together package; it was going to be with something that Denny had been wanting to try for a long time: a radical transplant of a small-block Chevy V8 into a first-generation Honda CRX, the engine driving the rear wheels.

The Mongrel cars built for the past Challenges established the formula that Denny knew worked, since both of those entries were small, lightweight cars that had received big power and did well in the drag race portion of the event. With a little work, the package could be made to handle well.

The choice of an early CRX was easy, Crabill explains: “The first-gen CRX HF is the lightest, cheapest commonly available car. It weighs in at around 1745 pounds from the factory, and after looking at CRXs closely, as long as we were going to convert it to rear-wheel drive, I thought we could physically stretch the wheelbase to 90 inches to comply with NHRA rules [for the drag racing portion of the event]. “And I think the CRX looks pretty sporty, too.”

Chassis and Suspension

There were two 1986 CRX HF chassis used in the build. The first was purchased for $50, and had taken a hard front hit. Fortunately, the cost was completely recouped by selling the dash glove box, door speakers and miscellaneous interior pieces. That car was the source for all of the major exterior body panels from the A pillars back.

The second car was purchased for $150; it was rusty, but had good bodywork and glass. Again, since Challenge competitors are allowed to sell parts off their cars in order to recoup the cost of those cars back into their budgets, team members sold almost everything else off of the second car to recoup most of what they paid for it.

While these efforts yielded a usable set of body panels, the original Honda chassis underpinnings were clearly not appropriate for a domestic V8 to drive the rear wheels. So the intrepid Mr. Crabill and friends looked elsewhere for a suitable floor pan.

“A friend of mine had stripped an ’80-something Mustang for parts and was looking to get rid of the chassis and some of the parts he’d removed but didn’t need,” Denny explains. “We took it and cut the floor out to use for the CRX.”

The floorpans were trimmed quite a bit to fit, and moved backward somewhat to accommodate the engine’s location entirely behind the centerline of the front wheels.

Things were looking good for the team’s original plan at this point, but they had some additional items to consider in planning the build. “When the $2004 rules came out, they specified factory frame rails, which forced us to not build the custom front suspension I wanted,” Denny relates. “So we looked for factory components that were the equivalent of what I wanted to do.”

After doing a good bit of leg work, the team came up with a solution. “After visiting a lot of swap meets and doing a lot of research,” Denny recalls, “we ended up spending $600 for a complete C4 Corvette front frame and suspension, including brakes.” For a few dollars more, a set of well-used C4 wheels was brought into the bargain.

While he acquired most of what he thought was needed for the front end of the car, Crabill was still investigating his options for the rear. Many road racers and autocrossers probably wouldn’t consider a live axle for the rear when building a car from a more or less clean sheet of paper, but Denny thought differently.

He believed that a good four-link rear axle arrangement could be successfully employed for autocrossing, while maintaining the traction qualities that make live axles so popular for drag racing. Initially, Denny thought they’d have to fabricate the rear suspension links and locating points entirely. Fortunately, he found a rusty four-link kit for $150 at a Pennsylvania swap meet, which gave him most of what he needed to accomplish the job. He sourced the rear axle from a totaled 1996 Mustang.

At this point, to align the hard points and see how everything fit together, the team laid out the basic pieces in Denny’s garage. In general, everything looked okay, but there were some definite issues that needed to be addressed on the front of the car.

“The front suspension was really interesting to do,” he explains. “We didn’t want to use the transverse leaf spring because we couldn’t adjust the ride height, and it would have looked like a four-wheel-drive truck, as light as that car is. I found some old drag car coil-over shocks that looked like they might work at the Maple Grove swap meet for $15; I had to disassemble them, clean them up and paint them.

“I found the springs at the GMs at Carlisle meet, 550-pounders from a dirt track car; they still had clay all over ’em. Fitting and locating those coil-overs and shocks between the A-arms and arranging the anti-sway bars was challenging.”

Once he’d gotten the layout of the front suspension mapped out, he mocked up the engine and transmission location, and again found that there was some rearranging that needed to be done. “We ended up moving the engine forward and down from Chevy’s original location because we wanted the engine to fit under the Honda hood and windshield,” Denny explains. “Also, the alternator wouldn’t fit in its original location, so we had to mount it to the chassis of the car and run it backwards. Good thing we weren’t using a generator,” he laughs.

The engine was set so far back into the chassis that the team made arrangements to make the front clip removable to provide for access to the engine and accessories. A light tube skeleton was employed to attach the factory plastic Honda fenders to the grille and chin pieces, while the hood remains a separate piece.

As the team set about fabricating transmission tunnel tinwork to adapt the Mustang floor pans and Corvette frame to the CRX body, they found that there wasn’t much room for pedals in the footwell once the roll cage was figured in.

At one point, they considered putting the throttle pedal up on the transmission tunnel, more than a foot elevated and to the right of the brake. When they mocked up the driving position, however, consideration was given to the idea that it probably wasn’t going to be easy for autocross drivers who were unfamiliar with the car to get comfortable driving it in just a few tries, so a somewhat more conventional pedal arrangement won out, involving a gas pedal hand-fabricated out of scrap tubing.

After all of the experimentation and compromises made at the front and passenger compartment of the car, the final arrangement and build of the four-link rear suspension and Mustang axle went relatively conventionally, though adapting the swap meet sprint car anti-roll bar arrangement to the drag car suspension required a bit of planning. Also, a fair bit of bodywork needed to be cut away to clear the rear tires.

When asked what was the most difficult part of the chassis and suspension builds, Crabill shrugs and smiles. “It’s all just metal,” he says.

Driveline Decisions

Once the chassis was constructed, it was time to get serious about the powerplant. Used small-block Chevy parts are cheap and easy sources of prodigious power, so it made sense for the team to use one for this project, particularly with the Corvette frame and suspension.

Denny scrounged for the engine’s foundation: “I got the block, crank and rods—from a van—in a trade for the two CRX drivetrains and what was left of the Mustang. I couldn’t come up with a full set of pistons, so we used a mismatched set of sprint car flattops that I got at the Maple Grove swap meet. The heads came in a trade for the van heads and some other stuff. We used epoxy to seal some cracks and make the heads Challenge-ready.”

Denny acquired a set of exhaust headers at a swap meet, but the team had to modify the front driver’s-side primary tube to clear the steering shaft after the engine relocation. The Holley carburetor and Weiand Racing Enterprises intake were found at the Carlisle All-GM Nationals swap meet, and the kitchen strainer air cleaner came from Wal-Mart in a pack of three. (The other two were last seen in the Crabill kitchen.) Denny had previously bought a small aluminum fuel tank to use for the car, but an acquaintance was willing to trade him for a nice black plastic one.

The two-speed Powerglide transmission and shifter came as part of a package of parts bought from a guy who was cleaning out his garage. Fortunately, the purchase netted some other items that weren’t needed for the project, so they were sold off to drive the costs down. While the Powerglide was nice to have, it didn’t have a valve body, torque converter or flex plate, but Crabill had purchased suitable items at the same swap meet where he got the pistons.

While these guys made implementing their unique plan look much easier than it really was, not everything went perfectly. The planned cooling system for the car was originally going to include a pair of micro-midget (think of karts that look like sprint cars) 8×12-inch radiators arranged in series, with 12 computer cooling fans to pull air through them at low speeds. As neat as that sounded, it just didn’t keep the engine running cool enough, and very late in the game the team was forced to order a radiator out of the Summit Racing Equipment catalog.

A used MSD 6 AL ignition, coil, plug wires and a box of used gauges were received in a trade for a used fiberglass Mustang hood. The gauges that weren’t used in the car were sold off to reduce the original cost of the hood.

Show and Go

One of the trends in traditional hotrodding during the past few years has been the unfinished black primer look. This look has spread to other auto enthusiasts, and Denny, Brian Keener and Jamie Redcay, visual trendsetters in the Challenge community with their work on the Mongrel Motorsports $2002 and $2003 entries, thought about that look and how they could apply it to the $2004 CRX.

“Coming in as Crabill Racing this year, we thought we were flying a bit under the radar, so that’s how we came up with the Stealth Bomber paint and graphic scheme,” Denny says. He also notes with a laugh that the spray can semi-gloss paint touches up easily and unnoticeably.

GRM Challengers are a resourceful bunch, and many have excellent fabrication skills, but Crabill & Co. have consistently shown a knack for hitting home runs on the visual, engineering and performance fronts.

As technically spectacular as it is, this CRX is no trailer queen. It knocked out an impressive 12.337-second quarter-mile ET for sixth at the Challenge drag event—almost as quick as a new $80,000 Dodge Viper—and made a 55.017-second lap of the Challenge autocross course, only three-quarters of a second away from FTD and good for seventh in that event.

Although Denny did much of the work himself, he gives a lot of credit to the team members. “Jamie Redcay and Brian Keener did a great job on the graphics and paint, Joel Barnett did the engine work, Pat Brown and Patrick Caherty helped out with the braking system, Jerry Shaffer’s contribution was his usual heckling and moral support, and Chad Brodbeck did a lot of work with the overall construction of the car,” he says.

Why?

Ask Denny why he and his friends continue to turn out such impressive entries in the Challenge year after year, and he replies that there’s actually a positive message behind it all: “We build these cars to show people what is possible if they apply themselves.”