1994 Pontiac Firebird - When LT1s Attack

Since the plugs in the '94 'Bird were no doubt the factory originals, it was about time to give this baby a tune-up. Stock replacements probably would have worked fine, but we plan to make some decent power down the road so we went with the new ZEX Power Tune plugs (PN 82070-8) for naturally aspirated applications up to 400 hp. These babies sport four ground straps, unlike traditional plugs that use just one, for a cleaner center electrode that doesn't have to rely on merely the heat range to keep from fouling. The ground straps are constructed of a durable nickel exterior with a copper core for better spark transfer than even iridium or platinum. This will help prevent detonation by transferring heat faster. At about $57, they are quite reasonable, too.

The plugs are gapped to .050 as per GM's specs, which you can find on the radiator support, then coated with antiseize before going into the heads. Putting the plugs in before the headers negates the use of a special plug socket with an open end.

Getting the driver side header situated correctly required an extra set of hands just like on the passenger side. Eventually Pedro and Junior got the header sitting flush to the head, slipped in the provided gaskets, and tightened the provided Grade 6 hardware.

The EGR tube is connected on the passenger side header with the supplied hardware and gasket. A 1/4-inch bolt secures it, tightened down with a 5/16 wrench.

The two-piece Y-pipe is loosely connected and bolted up to the headers with the supplied 9/16 bolts and gaskets. The junction between the driver side extension pipe and the Y-pipe is treated with antiseize,...

...while the bolts receive blue Loctite. A clamp prevents any leaks with the slip fit driver side extension and the Y-pipe. The last step is bolting the hanger back up.

In order to match up the MONZA Universal 3-inch cat to the Y-pipe and cat-back,...

...the ends of the stock cat need to be cut off and welded to the aftermarket unit....

...Usually, Junior farms out any welding duties to a local welder, but he managed to come through for us in a pinch.