A YJ With a Chevy LT-1 Engine
Step By StepView Photo Gallery
From the first moment we heard the throaty growl of this red 88 YJ coming up the hill, we knew there was something special under the hood.
Owner Larry White of Temple City, California, a machinery mover by trade, is accustomed to having a lot of power under the hood in his big-rig Freightliner. Thats why, when we opened the hood of his Wrangler, we werent surprised to see a 94 Chevy LT-1 350ci motor. So begins the saga of how Larry, an ordinary trucker from Southern California, appropriated his daughters bright red Barbie Doll Jeep (with a stock four-banger at the time) and transformed it into a hot commodity.
It started out ordinarily enough. After Larrys daughter, Julie, drove the vehicle to high school for a couple of years, she gave it to her Dad in exchange for a different car. Larry and his son Kevin decided to turn it into a project and build a high-performance off-road machine. According to Larry, the Chevy LT-1 engine swap (out of a late-model Pontiac Firebird) was the logical solution for obtaining high-performance status (300-plus horsepower and 300-plus pound-foot of torque) while also meeting local smog requirements.
Larry says, The motor has a real nice torque curve and redlines at 5,800 rpm, while at the same time, it has the ability to work well at low rpm. It has 10.5:1 compression, a roller cam, aluminum heads, and tuned-port fuel injection, all of which, he thought, were a plus for off-roading. Larry got the complete engine (with only 28,000 miles), transmission, and computer from a wrecking yard in Florida, extracted from a car that had been rear-ended. He claims the swap went rather smoothly, explaining that the engine fit better in the YJ than it did in the Firebird. Nevertheless, engine swaps take considerable knowledge and a fair amount of planning to get the job done right.
To aid in a smooth swap, universal motor mounts from Advance Adapters were used. To clear the front driveshaft, a remote oil filter had to be installed. Larry ripped out a lot of the factory wiring, retaining just the wires for the stock gauges, ignition switch, and headlights to keep the engine compartment simple. From there, with the help of Howell Engine Developments, a simple wiring harness was made that linked the GM computer to all the sensors on the engine. The original GM power steering, 120-amp alternator, and A/C compressor remained intact.
As you can see, the LT-1 V-8 was left fairly stock (for reliability) but now gets a little power boost from the K&N filtercharger in its custom airbox. To keep it all running cool, a custom-built Griffin radiator was installed. The exhaust setup was built by Scotts Header and Muffler and expels the noxious fumes. Power threads through a 4L60E transmission augmented by a B&M trans cooler and a Shift Plus electronic shift improver, continuing on to an Atlas II transfer case. From there, a pair of Tom Woods driveshafts send the power to custom-built axles put together by Tri-County Gear. A Dana 44 with an ARB Air Locker sits up front, while a full-floating Dana 60, locking Warn hubs, and a Detroit Locker make up the rear. Both have 4.88:1 gears and 30-spline axleshafts.
As for the suspension, Larry chose the Warn Black Diamond Kit. The process took him considerably longer than he anticipated, due in part to the fact that the engine and transfer case had to be readjusted (nearly 1½ inches) so the skidplate would fit correctly. Evidently, this problem wouldnt have occurred if the stock motor, tranny, and case were used. Nevertheless, the 47 hours of painstaking labor paid off, since Larry reports that the Black Diamond works like a champ. This killer suspension makes plenty of room for the 33-inch Goodyear MTs that spin on 15x12.50 Center Line wheels. The spray job is the work of Randys Signs out of Irwindale, California, appropriately designed to match the rigs disposition. The flames were painted over the existing Wrangler Red basecoat.
Diamond plating was added below the doors and to the rear corners to protect the body from trail dings. The nerf bars were supplied by Sun Products and provide defense as well. A chrome bumper up front sports a highlift jack and a Warn XD9000i winch. Other trail essentials include towhooks, a chain, straps, and a shovel attached to the spare tire. A customized 28-gallon fuel tank supplies plenty of fuel for long-distance assaults.
Inside, Larry left his rig in stock condition with the exception of an Auto Meter tachometer and a Magellan 2000XL GPS. He figured being lost and having a blown motor were a bad combination.
This rig is a solid example of how bone-stock can be transformed into bad-to-the bone with the help of just a few good ideas. The big engine swap was an important part of this process, and according to Larry, it was a lot easier with all of the aftermarket products available. Larrys vision of transforming a tame little YJ into a V-8 beast really paid off, and we rightfully give him the thumbs up.