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Engines
There are a few areas of the drivetrain that should receive extra attention when building a Pro-Touring car. Some of these areas don’t get much attention on street rods and Pro-Street cars. Most of those cars don’t see the hard driving a Pro-Touring car will see. When you push your car to the limits and beyond, weaknesses in your engine, cooling and oiling systems, transmission, and clutch will become more evident. The following chapter will be dedicated to these areas and more.
Engine Swaps
To start off, this section will have information some purists will deem ludicrous and downright horrible. With that said, read on.
Swapping in a non-original engine is done for many reasons. Here are a few of them: gain more power, increase the “oooh” factor, save money, or just use what you have laying around. The most common engine swap in the world is to swap from a small-block Chevy to a big-block Chevy or vice versa. Any transmission that fits a big-block Chevy will fit a small-block Chevy. Buick, Oldsmobile, and Pontiac (commonly referred to as BOP and BOPC when Cadillac is added) transmissions interchange with each other, but require different flywheels or flexplates in some cases.
The finger in the picture is pointing to the frame stand. It bolts between the frame and the motor mount (which bolts to the engine block). If you had Pontiac Firebird frame stands, you could bolt them to this Chevy Camaro frame. This makes it easy to install a Pontiac engine in a Camaro, or vice versa. GM did this to save money and time. It helps when doing engine swaps too.
Frame stands make swapping easy with some cars. The frame stands I am referring to are the metal brackets that bolt between the subframe and the engine mount. All the first-generation F-body and ‘68 through ‘74 second-generation X-body engine stands can be interchanged. All the second-generation F-body and the ‘75 through ‘79 X-body engine stands interchange. All A-body engine stands interchange, and so do the B-body frame stands. The frames either have multiple drilled patterns for the different engine stands, or the frame stands use the same holes. GM did this to save money and time when engineering and assembling at the factory. To you and I, this all means that with right frame stands, a ‘68 Pontiac 400 engine can be bolted in a ‘69 Camaro or a ‘74 Oldsmobile Omega. With all the different frame stands available, and all the interchangeability, just about any GM engine will mount in just about any GM body. Of course, there might be some interference with a firewall here and there, depending on what distributor you use.
This ‘70 Pontiac GTO owned by Andrew Borodin is equipped with a 502-ci big-block Chevy. The swap was easy since the GTO frame was shared with the Chevy Chevelle. Andrew installed Chevelle frame stands, so the 502 bolted right up. The Pontiac transmission would not bolt directly to the Chevy engine, but he installed a T-56 to fix that problem. (Photo credit Andrew Borodin)
If you have a rear-wheel-drive 1963 through 1992 (in some cases, earlier and later) Chevy that was available with a small-block engine, and want to stick with a Chevy engine, that is easy too. The inline 6, small block, and big block all had different frame stands. Just swap the stands and bolt in a Gen-I and -II small block or a Gen-IV, -V, or -VI big block.
Then there are the guys who use what they have laying around the garage. Using what you have laying around is a good way to save a little money when building your project. Maybe even go as far as swapping an engine from a different manufacturer. Take Ron De Raad for instance. He is building a ‘68 Camaro. It’s mini-tubbed, has a Martz Chassis front clip under it and a full cage, as well as all the full-on Pro-Touring goodies. He just happened to have an 800+ horsepower twin turbocharged 302-ci Ford engine lying in his garage from a project that came and went. It only made sense to use a nice powerplant like that in a nice project car.
H-Body Engine Swapping
The only four-cylinder GM I am covering in this section is the H-body, so they get their own section, due to modifications specific to them. If you own one and want to swap out the 2300 four cylinder engine for something more powerful, you could try to scrounge up a rare 122 cid twin-cam Cosworth and drop it in, or you could choose from many other more powerful and readily available engines. A Saturn DOHC, a Quad4, or Buick V-6 will give you more power than the 2300. An LS1 or LS6 would be nice and light for a V-8. You could go the traditional route by bolting in a Gen-I or -II small-block or big-block Chevy V-8 and buy special engine mounts and other H-body parts from Robert Gumm of www.v8monza.com. He sells custom rubber mounts that allow you to bolt small- and big-block V-8s into the ‘71 through ‘80 H-body. They are modeled after the factory mounts (which are no longer available).
Just like any car, when installing a V-8 where a much smaller engine was previously housed, check all front suspension and drivetrain components to make sure they are in tip-top shape. Builders have found weaknesses in the H-body front frame when applying lots of V-8 torque. The front frame rails start to spread. The K-member under the front of the engine is stamped steel and has slotted mounting holes. The stamped steel flexes and the slotted mounting holes allow too much play. Welding extra bracing to the K-member and closing the slots so they are round holes increases the rigidity.
The exhaust gets tight in the Vega-sized engine compartment. Full-length headers usually hang down too low, and the fenderwell exit versions limit the front tire width and tend to bake the master cylinder and brake fluid. Sanderson makes a beautiful set of shorty headers that fit the small block. The steering shaft runs between two of the primary tubes, so the shaft must be removed and reinstalled once the header is in place.
The Vega looks a little sedate with Chevy S-10 15x7-inch wheels, but it really moves with an LT1 and the light body. It has a 700R4 transmission, a Monza rear-axle housing equipped with Moser axles, and some ‘98 S-10 12-inch rear disc brakes. The front brakes and spindles are adapted from an S-10 using special adapters from v8monza.com. (Photo courtesy Dave English)
Gen-II Engine Swaps
Putting a Gen-II small block (LT1 or LT4) in a car previously equipped with a Gen-I small-block Chevy is basic, since the transmission and engine mounts are the same. The Gen-I and -II engines share the same transmission bellhousing bolt pattern, so the transmissions from either generation fit. Other than that, there are a few differences that make the swap more difficult. The LT1 is externally balanced, so they use a specific counterweighted flywheel or flexplate. Radiator hose routing is tougher due to the placement of the water inlet and outlets on the engine. The stock fuel-injection intake manifold is very low profile, so hood clearance is not an issue unless you swap it for something else that is taller. Using the factory accessory brackets may require notching the frame if you intend to use the low-mounted air-conditioning compressor. The oil pan from the Gen I starting in 1986 fits the Gen II, so there are plenty of oil pan configurations available. One should be able to fit your engine compartment and frame constraints.
When hot rodders first started putting the LT1 put into older cars, the factory engine management system was used. Using the stock wiring harness proved to be a huge job. These days you can save yourself some time by using custom wiring harnesses and accessories by Painless Performance Products. Or you can totally bypass the factory management system by tossing it in the scrap pile, and install a complete aftermarket engine management system, such as an ACCEL/DFI.
This LT1 was swapped into a ‘69 Camaro. You might think that is a typographical error, but it’s not. The engine was converted back to an earlier-style rear distributor. The owner, Bob Spears, decided the stock GM OptiSpark distributor was not reliable enough. The water pump is the only hint that this is an LT1.
Gen-III Engine Swaps
The Gen-III small block (LS1 and LS6) has been available since 1997. Like all aspects of hot rodding, not even specific to Pro-Touring, it was only a matter of time until people wanted the latest technology in their older vehicle. People like Tyler Beauregard have taken the Gen-III swap to a whole new level. They are swapping in the Gen-III engine along with the C5 Corvette torque tube and rear mounted transaxle. This is highly involved because the torque tube and drive shaft have to be lengthened or shortened to the correct length of the car’s wheelbase. In some cases, builders are getting more extreme and lengthening the chassis and bodies of the vehicle to fit the stock length C5 drivetrain.
The less invasive use of the Gen III is to swap in the engine along with a transmission from the ‘98 through ‘02 F-body, since it has a different transmission bolt pattern than the Gen I and II. This has been made fairly easy by a few aftermarket companies offering custom motor mounts. One of those companies is BRP Hot Rods. They offer custom Gen-III mounts so you can bolt directly into the frame stands in the car. The stock GM accessory mounted air-conditioning compressor mounts low like the LT1 system, so notching the frame for clearance is necessary on most older GM frames. The coolant hoses come out of the water pump housing at an awkward position, which adds a little difficulty to the swap. If you want to mix a little old technology with new technology (and less wiring hassels), you can bolt a carburetor on top of your LSx engine by using a GM Performance Parts or Edelbrock intake manifold. Since these engines don’t have distributor, MSD Ignition and Edelbrock offer an electronic controller to help make the swap easier. Painless Performance also offers a wiring harness to take some of the pain out of connecting the factory engine management system to the Gen III. GM is currently offering three different oil pans for Gen-III engines. They are for trucks, F-bodies, and Corvettes.
The LS1 has an aluminum block and heads, which makes it a lightweight and powerful engine to swap. John Bzdel used a modified F-body oil pan and homemade engine mounts to shoehorn the engine into his ‘88 SS Monte Carlo. It is a clean installation, and at a glance looks like it was meant to be there. (Photo courtesy of John Bzdel)
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