The '94-'96 Impala SS's were an unusual car, in reality it was a 9C1 (police interceptor) Caprice just dolled up and slightly more enhanced. The '96, also the last year, were the ones to have. To this day I am not sure why, but in the final year, they actually made it a floor shift (previous two years it was still on the column), they gave it all analog gauges (previous years had the same digital dash as the Caprice) and it was OBDII, whereas previous years were ODBI. There were other little tidbits changed here and there, but those were the big changes. Both of ours (spouse still has hers) were '96's. I have the programmer for flashing the ECU. They allow you to change just about every conceivable function on the car. You can even turn items off and no DTC's will be set if you start disconnecting them, like the final set of O'2 if you want to make it cat delete, or the air pump (which pretty much didn't do anything for emissions anyway).

The LT1 was a bit of a red-headed step child engine. Rather than start with a clean slate, GM took an engine from 1955 and tried to meld it with modern ideas. I applaud that. Just some of the execution was baffling. It had some fantastic ideas incorporated into it. The most notable was reverse cooling. This is brilliant, too bad it's patented, because it makes the most sense. Cool the heads first, then the cylinders By dumping cold coolant into them this engine with cast iron heads with 10.5:1 compression could run on 86 octane fuel and have no worried about detonation.

Evans cooling took GM to court and they settled out of court, funny how right after the Gen II LT1/4 series engines were canceled and they started on a fresh design, the LS series. Although no other engine to my knowledge has reverse cooling.

The terrible change they did was that silly Optispark distributor wedged behind the water pump (driven right off the camshaft front) and front crank pulley. Since the engine was still based on the Gen I small block they added a stub in the back to drive the oil pump where the distributor used to be.

The problem other than location of the Optispark is they equipped the engine with a dual photo sensor for the pickup (low and high resolution) as a result the ECU knows exactly which cylinder is firing. At this point they should have made it coil over plug ignition, but no, there's distributor cap and rotor. The ECU however can and does advance and retard individual cylinders.

Now my '93 Grand Marquis has coil packs, this certainly wasn't out of the realm technology. Heck my Grand Marquis has the bare bones basic multiport fuel injection from Ford. Heck it doesn't have knock sensors or even a manifold pressure sensor. It cannot tell when it's detonating, in fact it has an octane bar (shorted plug) in the harness. If you run a higher octane fuel you can remove the short and it will switch to a little more aggressive timing curve.

The GM LT1 was advanced in many areas, but a little backwards in others. If they would have just made it coil over plug and not even put an electric air pump on it, it would have been a really good and easy engine to work on (well in a B-body anyway).

You've heard that the transmissions were weak. This may substantiate that rumor.

This is the output shaft from my Impala's 4L60E. I sheared the output shaft in two. The collateral damage was extensive, not to mention the noise it made when it let go. The bottom tray is everything that ultimately was replaced. Not pictured is the torque converter, that was replaced too.

This as you say is a prime example of when you start upping the power of the engine and other parts of the driveline start to fail.

Cheers.

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