Pro Touring 1981 Chevy El Camino - Planning For Power

Building a Budget Supercar on Paper

Scott Crouse Jun 1, 2002 0 Comment(s)

Step By Step

One of the major dilemmas in choosing to build a California smog-legal 350ci or 383ci engine is the state’s emission law, which requires the restrictive factory feedback Quadrajet carburetor, EGR intake manifold, and single catalytic exhaust system.

Barkley wanted to increase the horsepower of the Impala’s LT1 so he added a Crane hydraulic cam, matching valvesprings, and 1.6 roller rockers. He also had some minor bowl work and a valve job on the cylinder heads.

The 4.3L ’85-’87 fuel-injected El Caminos came from the factory with a baffled fuel tank that featured an in-tank fuel pump. Without a baffled fuel tank, fuel slosh is likely to occur causing fuel- starvation problems.

The bolt holes shown at A, B, and C are where the late-model LT1 350ci engine motor mounts adhere. The extra hole (D) allowed engineers to move the motor mount rearward to provide clearance for the Impala’s air-conditioning compressor.

The 4L60E and TH700-R4 transmissions are slightly longer and larger than the TH350 and the TH200-4R. This requires a custom crossmember and driveshaft to install into an A/G-body vehicle.

In order for Barkley’s Pro Touring project to keep up with the exotic sports cars, the factory 10.5-inch front disc brakes are going to make way for Baer’s 13-inch brake kit.

This is the area where the frame will have to be notched if the factory Impala accessory configuration is used.

If Barkley were to use the LT1 Impala accessory configuration in his El Camino, this mount would have to be placed approximately 1 inch farther back to match the Impala frame-mount location.

How often have you walked the isles of an automotive event daydreaming about building the perfect ride? The reality is that very few of us act on those thoughts. Imagining the perfect ride is like opening a book and reading the first paragraph. It's the introduction to the rest of the story.

John Barkley has played the same "what if" game but finally landed on a vision of building a Pro Touring '81 El Camino. He acquired the El Camino from a fellow Chevy enthusiast who had previously installed a high-performance 350ci and TH200-4R transmission. While the stout small-block offered plenty of power, California's tough emissions laws banned it from the streets. Barkley's only option was to extract the offending engine and replace it with something more emissions friendly. This bump in the road presented Barkley with several options. Before he began, Barkley established the "rules of engagement" that the El Camino would have to play within. Barkley wanted a daily driver, but he also demanded the performance of an exotic sports car. While these parameters may seem polar opposites, they're quite close to Pro Touring.

After much deliberation, Barkley came up with four possible directions his supercar could follow. The first route involved modifying a 305ci engine. Since Barkley's been keeping up with CHP's "My Generation" Camaro project car, he had a good idea of what the smog-legal, budget 305ci engine could produce and decided he wanted more. His second option was to build a mild 350ci engine and recycle the overdrive TH200-4R transmission. Chevy High has been planning this engine build for several months in the "My Generation" Camaro project car and tipped Barkley off to the potential power this setup could produce. After much debate, he decided that building the 350ci would be too much like his current combination, only with less power to keep the smog police away. Even though a modified 350ci is probably the best bang for the buck, Barkley wanted something different.

Another idea was to build a 383ci that would create massive amounts of torque. However, upon investigation he found that emissions laws required a factory feedback Q-jet carburetor, EGR intake manifold, and single catalytic converter in order to comply with the California visual inspection. While changing carburetors for a quick smog test isn't that difficult, Barkley decided to pass. He figured that adding cubic inches to the engine only to restrict the amount of airflow isn't the smartest route.

Finally, after pondering numerous combinations, Barkley chose an LT1 engine and 4L60E-overdrive transmission from a '95 Impala. The LT1 fuel-injected engine is capable of providing plenty of power and reliability, while the 4L60E-overdrive transmission would allow the use of a steep rear gear.

A stock '95 Impala LT1 engine is capable of producing 260 hp but Barkley wanted more. He plans to add a Crane Cam, matching valve springs, and 1.6 roller rockers. He'll also have some minor bowl work and a valve job done to the cylinder heads. The LT1 fuel injection requires a high-pressure return fuel system to supply the fuel injectors with the proper amount of pressurized fuel. Since Barkley's El Camino originally came equipped with a carburetor, his entire fuel system requires re-plumbing. The 4.3L '85-'87 El Caminos with factory fuel injection were offered with baffled fuel tanks that feature an in-tank fuel pump. These particular fuel tanks are a direct replacement for Barkley's El Camino.

The LT1 and 4L60E transmission are a great choice when used as a factory package, but they can create some interesting dilemmas when installed in a vehicle originally equipped with a first-generation small-block and TH350 transmission. A late-model LT1 Impala engine places the air-conditioning compressor on the lower passenger side requiring an extra motor mount hole on the left side of the engine block. This extra mounting hole allows the motor mount to be placed farther back on the block to clear the air-conditioning compressor. Since Barkley was installing a '95 Impala engine into his El Camino, he had two choices. He could have used the factory Impala LT1 accessory brackets and relocated the passenger-side frame mount approximately one inch back. The front passenger-side framerail would also have needed to be notched for compressor clearance. Instead he chose to convert his Impala engine over to LT1 Corvette accessory mounting brackets, which moved the air-conditioning compressor to the upper driver side of the engine. Had Barkley decided to use a Corvette LT1 engine, the oil pan would have required replacing. Converting to Corvette LT1 accessory brackets allowed Barkley to use the standard (non-Impala) motor-mount bolt pattern on the passenger side of the block and keep the frame mount in the factory location.

The 4L60E transmissions closely resembles a non-computer-controlled TH700-R4 design. Both of these transmissions are larger and longer than a TH350 requiring a custom driveshaft and crossmember if installed into an A/G-body car. The TH200-4R is similar in length to the TH350 and would eliminate the need for custom installation pieces while offering the 0.67 Fourth gear overdrive. Most '80s El Caminos are factory equipped with 2.41 gears and a 7.5-inch 10-bolt rearend. Since Barkley is using the 4L60E-overdrive transmission, he plans to leave the stock 7.5-inch rearend housing in the car and install a posi-traction unit with 3.42 gears.

A high-performance LT1 and 4L60E transmission are capable of producing plenty of power to the rear wheels, but for Barkley's El Camino to be the true road warrior he desires, it's crucial that the suspension be first class. After referring to several suspension stories in Chevy High Performance, Barkley decided that lowering the truck, shortening the springs, and increasing the diameter of the sway bars would offer the best bang for his buck. He consulted Hotchkis Performance and a sway bar kit seemed like the way to go. The 1-inch solid front sway bar and 1-inch solid rear sway bar come with all the necessary bushings and end links. With the upgrade bars in place, Barkley also added a Hotchkis 1-inch lowering-spring kit to create a lower center of gravity and improved handling. The last thing on Barkley's list of handling upgrades is a set of high-performance tires and wheels. Barkley plans to eventually use a set of '99 C5 Corvette 17x8 fronts and 18x10 rear wheels wrapped in factory rubber. Of course, this will require wheelwell modifications and wheel spacers.

For the average enthusiast thinking about bolting on some wide wheels without the hassle of modifying wheelwells, Barkley recommends using '91-'92 Corvette 17x8 wheels on the front and rear. Maximum tire size will vary according to the ride height of the vehicle.

Once Barkley figured out how to accelerate his El Camino through the corners he had to come up with a way to stop it. This led him to Baer Brake Systems in Phoenix where he learned that his El Camino could be treated to some monster 13-inch front rotors with the proper spindle. In order to install the larger rotors, Barkley has two options. He can use the factory spindle from a 12-inch rotor B-Body car and match it with Baer's B-Body spindle kit, which requires aftermarket upper A-arms. The other route is to add Baer's complete13-inch brake kit that supplies all the necessary parts including the special spindle. This particular kit has been designed to eliminate the need for aftermarket tubular arms.

The next best alternative to the aftermarket 13-inch Baer setup is to hunt down a '77-'96 B-body station wagon or police car with factory 12-inch rotors. In the event that you come across a Caprice (B-body) with 12-inch rotors, the bolt spacing is 5 inches versus the El Camino's smaller 4-inch pattern. If you want to keep the 4-inch bolt spacing with the larger 12-inch rotor, you'll need to order an '88-'92 1LE Camaro rotor.

There are many different rear-brake systems to choose from. While Baer offers its 12-inch rear disc conversion kit for the 7.5-inch rearend, Barkley managed to get his hands on a 10.5-inch Stainless Steel Brakes conversion kit. While the larger 12-inch rear brake kits may seem to be the ultimate choice, be aware that the massive rotor and caliper design requires at least a 17-inch-diameter wheel to clear the special caliper.

Designing the perfect automobile in your imagination is one thing, but actually making it happen is another. Barkley's momentary thought of building a Pro Touring El Camino is currently transforming into an ongoing labor of love. So the next time you catch yourself daydreaming of the perfect ride, be careful what you ask for—you might just get it.

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