The engine bay of a '94-'96 Caprice/Impala is easily the most spacious of any LT1-equipped
Man, time flies. It seems like just a couple years ago when GM introduced the first major renovation of its small-block, but of course, that was back in 1991 for the '92 Corvette. At the time, one of the big deals of the Gen II engine was the Opti-Spark ignition system, which was driven directly off the cam and treated the engine "like eight one-cylinder engines," according to GM, in reference to the system's agility in constantly adjusting ignition timing based on need. The Opti-Spark system still used a distributor and conventional spark-plug wires, but it seemed to be considered a maintenance-free device, at least if the 100,000 spark plugs were any indication. But now the youngest of LT1-powered cars have been on the road for about nine years, and it's pretty common to see them with well over 100K on the clock. What's more, time has shown that LT1s tend to be hard on their ignition systems, if only because the plug wires are routed behind the exhaust manifolds where they are frequently baked prematurely. The resulting increases in resistance can in turn stress the distributor cap, and that's where a lot of guys get hung up.
If it isn't the fear of the unknown causing hesitation in tearing the system open, it's the lack of available parts, or at least their unusually high cost. Apparently, since GM didn't intend for this system to need frequent maintenance, the cap and rotor were not initially available on their own, and a whole new Opti-Spark unit had to be purchased. Later, the cap and rotor were sold separately, but often at a price that made the complete Opti unit seem more attractive. Now MSD has stepped up to offer its own version of the Opti-Spark cap and rotor, and by the time you read this, a complete, billet-housing Opti-Spark distributor. Both the cap-and-roller sets and complete distributors will be offered in early and late designs to cover all LT1 applications. We'll tackle the simple tune-up parts and illustrate that getting the job done on a Caprice/ Impala, isn't so bad. Have a look.
Within a few minutes, and with a few twists of a flathead screwdriver, the air inlet ducti
If GM hadn't used one of the water-pump bolts as a mounting stud for one of the air-pump b
The air-pump bracket has three mounting bolts, and a 916 will get them if you don't have a