Autocross: It's a Jeep Thing

By Staff Writer
Jan 12, 2018 | Jeep | Posted in Features | From the May 2012 issue | Never miss an article

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story by alan cesar • photos as credited

What’s a yellow Jeep doing on an autocross course? Not that its color matters so much—the body could be decoupaged with Maxim centerfolds and then covered with glitter, but the most salient point would still be that a mutated SUV is swerving through the cones at an event full of sports cars. It looks completely out of its element among the production machines that make up the rest of the field, but on the hardcore, anything-goes E Modified grid at Nationals, well, even there it’s a head-turner.

Del Long, the owner and builder of this concoction, started out with an Allison Legacy Race Car chassis. That’s a 3/4-scale replica of a NASCAR Sprint Cup car intended for a particular spec series, but what made it useful to Del was the lightweight tube frame. As prepared for that series, an Allison Legacy weighs 1400 pounds dry, including its Mazda truck engine and transmission. The rest of the foundation on Del’s chassis looked solid, too, as it sported a double-wishbone front suspension and three-link rear live axle.

Del, of course, didn’t have to retain the stock car body. That’s where he faced an interesting choice: He had to skin the tube frame with something, but what?

“There’s only so many cars that are front-engine, rear-wheel-drive, and have an 80-inch wheelbase. There’s the Sprite, the MG Midget, maybe a few TVRs,” Del grins, “and the Jeep.”

Faced with those choices, the eccentric brain ahead of that white ponytail opted to pick the oddball. Del has dubbed it a 1946 CJ2, a Willys Overland-era ute. Its modern sans-serif sticker logos are a bit of an anachronism, but no one seems to mind.

The boxy shape has its advantages when it comes to building a complete shell from scratch. “It’s a simple body. Any blacksmith can make a Jeep,” he says.

It’s true. This car is all flat sides and simple bends; no compound curves or complex angles here. The .04-inch-thick, plastic-coated aluminum panels—the same stuff used for road signs and dirt-track cars—are simply screwed down. Dzus fasteners are used on the removable sections.

Trail-Stomping Grunt

Twist the Jeep’s fasteners and lift off the hoodlike piece, and be careful that your eyes don’t fall out of your head. The 125-horsepower engine from that aforementioned Mazda mini-truck is long gone; Del started out with a rolling chassis, so his engine bay was a blank slate.

A junkyard provided the turbocharged four-cylinder from a 2009 Chevrolet Cobalt SS. These engines are known to be durable and take well to minor modifications. This one was also a bargain: Just $2000 bought 260 late-model horsepower straight away.

That’s a substantial amount of power, but it wasn’t quite enough to make Del competitive in the ultra-bonkers E Mod class. He needed more. So he scrounged up an inexpensive turbo plumbing kit on eBay, fabricated a short side-exit exhaust, then called up Vince J. Geglia II at Trifecta Performance. Vince was able to write fuel and ignition maps optimized to use high-octane, low-cost E85 fuel.

Del hasn’t actually put the chassis on a dynamometer, but his research shows that similarly modified Cobalt SS engines typically make 350 horsepower and an eyebrow-raising 375 lb.-ft. of torque. He says the switch to E85 accounts for about 35 of those ponies. At this point he’s pretty certain the stock fuel pumps—the direct-injected engine has three of them—plus the injectors and turbo are about maxed out.

Of course, if custom intake and exhaust plumbing were required to fit the Ecotec inside the Allison chassis, then a front-wheel-drive transaxle wasn’t going to cut the mustard either. Del mated the Cobalt powerplant to a Doug Nash two-speed, quick-change transmission. The engine’s trail-worthy swath of torque makes even two gears unnecessary, though, as a driver can simply put it into high gear right from the starting line.

That transmission has an interesting story of its own, dating back to the early ’70s. California circle-track racers at the time had a popular Sportsman class that disallowed quick-change differentials. Miffed but determined, Doug Nash decided instead to make a quick-change gearbox that would skirt the rules so he could still swap gears at the track.

Del is happy with his Nash box, but these days they’re becoming very hard to track down. “Find me another and I’ll buy it,” he proclaims.

Since it shares a bolt pattern with early four-speed General Motors transmissions, Del bolted the Doug Nash trans to the Ecotec with an adaptor bell housing sourced from He then fabricated solid mounts to tie the drivetrain directly to the chassis.

All the Axle Articulation You’ll Need

This isn’t just an engine-swapped baby NASCAR, though—it’s been tweaked all around. The rear axle is a trick piece that started as a full-floating Ford 8-inch unit. A full-floating axle’s hubs are independent of the driveshafts, so its wheels and brakes don’t fall off if a driveshaft snaps.

Del narrowed the Speedway Engineering-sourced rear end to fit it to the chassis, but he left it wider on the driver side so its input yoke would line up with the offset powertrain. Camber and toe were built in when it was narrowed; Del had chosen an axle from Speedway Engineering with crowned splines to accommodate the angle.

The suspension is still more or less original Allison Legacy, but it, too, got a bit of a massage: All of the pickup points were moved. The quarter-inch steel ballast plate mounted at the bottom of the chassis—worthy of use as a skidplate—is now a full 2 inches closer to the asphalt. To avoid introducing bumpsteer with the lowered ride height, Del used washers to shift the steering rack upward.

That last change may have caused a minor issue at the SCCA Solo Nationals this year: Del’s drivers experienced some binding in the steering shaft after the first day, but the team ironed out the problem without much hassle. Bob Tunnell and Jeff Ellerby drove it to second and third place in class, respectively, and Patty Tunnell nabbed second place with the ute in E Modified Ladies.

Those impressive results came despite some decidedly low-budget solutions. Del uses heavy steel-body shocks available at a local parts store for $59 apiece. The front splitter isn’t exotic, either: It’s made of wood, something that more often gets in a Jeep’s way on the trails. But it works. After experiencing some teething pains at its first two events, this machine has proved itself extremely durable.

Muddin’ Buddies

Aside from the attention, a perk of racing a Jeep is the cult support. The brand has a huge, devoted fanbase. Del tells a story about meeting Wiggy Greacen, a Jeep fan, at another autocross event.

At the time, Del was having trouble with the cheap blow-off valve that came with his turbo plumbing kit. “It was not up to the task of holding as much boost as we wanted,” he recalls.

Wiggy had a solution back home: He offered to ship Del a sturdier unit in implicit thanks for repping a Jeep on the tarmac. Some time later, Del received a letter in the mail instead of a box of turbo hardware. Wiggy couldn’t find the blow-off valve in his garage, so he instead enclosed a check for $200 to go toward a new one.

In a nod to the purists—Jeep owners are notoriously critical of any attempts to reduce their ute’s off-road prowess—Del assures us that no Jeeps were harmed in the making of this vehicle. What, then, makes this a Jeep? Nothing beyond the stickers and a vague resemblance, though perhaps it has the soul of one, too.

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And since Del built it, much has been done to help improve it.

JimMurphy New Reader
1/17/18 10:02 a.m.

And we have an open seat rental policy on this Jeep - whoever (including ladies) wants to drive it can rent it AND if you are fast enough you can have a shot at driving it at National Tours and the Solo Nationals.  We are based in metro Atlanta.  And, BTW, Steve Brueck took third at the 2017 Lincoln Solo Nationals - not bad for a car that is not 100% developed.

Upgrades are a never ending process.


ps - it does have a chrome Jeep grill, the ONLY thing Jeep on it.

JimMurphy New Reader
9/20/19 4:30 p.m.


Chassis: Allison Brothers Legacy 80” Wheelbase Oval Track Race Car, modified for solo/autocross with both front and rear clips centered, lightened, strengthened and optimized suspension geometry.

Weight: w/o Driver = 1,575 lbs. Class required weight w/driver = 1,750 lbs.

Rear Wheel Horsepower: 450+ on E85

Engine: 2009 Chevy LNF 2 Liter, 4 Cylinder, DOHC 4 Valve, Turbocharged, Direct Injected; modified as follows –

Two mid-range power camshafts w/stronger valve springs with titanium retainers, new valve job, valve guides and valve seals, larger direct injectors/rail, Wiseco coated/lighter pistons, lighter/stronger Molnar connecting rods, balancer shafts/chain drive system deleted/holes plugged, mechanical water pump disconnected and propeller removed, stronger ARP bolts throughout, ATI under-drive crank dampener to compensate for the lack of balancer shafts, Powell Race Shop baffled oil pan, ported/matched intake manifold, upgraded turbo to continue boosting past 7,000 rpm, exhaust manifold and down pipe ported, ceramic coated and heat wrapped, remote oil filter w/-10an fittings and lines for easier filter access along with an AccuSump for pre-oiling. 2.5" diameter all welded intercooler piping with fan mounted air to air intercooler setup and Dial BOV, bigger/straighter/all welded air intake tube with much bigger AEM air filter. Autometer Autolite 2 mechanical oil temp gauge with 2 5/8" display and water temp gauge with 2 5/8" display. HP Tuning installed/programmed in the LNF ECU. Additional motor/transmission mounts and engine bay bracing.

Transmission: Doug Nash 2 Speed Quick Change, Quad Four Rods bellhousing, Custom twin disk clutch/pressure plate/flywheel (much lighter).

Driveshaft: Custom 14” long shaft.

Rear End: Speedway Engineering narrowed/offset Ford Mustang 8” housing, Jaws Gears aluminum center section w/4.62 gear ratio, True Track limited slip differential, Custom floating axles in housing with built-in toe-in and negative camber.

Radiator (located in rear): VW Scirocco w/electric fans and Autometer in-line water pump, aluminum tube direct routed between motor and radiator.


  1. Afco double adjustable, remote reservoir coil-over shocks, custom A-arms and adjustable sway bar. Rear – Afco double adjustable, remote reservoir coil-over shocks, custom three link trailing arms, custom adjustable panhard rod.

Brakes: Speedway Motors master cylinders w/residual valves, brake bias adjuster, Wilwood 4 piston calipers.

Steering: Speedway Motors quick ratio rack/pinion and 10” diameter steering wheel (take-off).

Wheels (Tires): REAL Racing aluminum – front 10x13 (20x10x13) and rear 14x13 (23x14x13)

Body: Custom .040 thick aluminum sheet made to look like a 1946 Jeep (80” WB) for E Mod Solo rules.

Data Logger with ever growing number of data points all over the Jeep.

Original Builder: Del Long, Cedar Rapids, Iowa

Version 2.0+: Chassis builder/tuner – Dan McMahan, Covington, GA

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