The Blue Oval Boys are back. The Ford Mustang reclaimed the streets in the early 1990’s thanks to the development of the fuel injected high-performance 5.0L V8 engine. Today, 225 horsepower is laughable from a big displacement V8 but in 1988 225 horsepower was impressive. Tack on 300 pounds foot of torque and we had a heavy hitting engine. And that’s exactly what the lightweight FOX body Mustangs packed from 1987 to 1992 (Ford changed the pistons and down-rated the engine to 205 HP in 1993). Best of all, this gem of an engine could be had in both the Mustang LX and GT in any configuration – convertible, coupe or hatchback.
And then the aftermarket got ahold of this new fuel injected 5.0L V8 and power figures went through the roof. Ford fully backed this performance engine with the release of various cams, intake manifolds and gear ratios. Supercharger companies popped up left and right with bolt-on kits for the 5.0 and in short time tuners had these engine putting down 300 horsepower and well in to the high 400’s with a whistler.
The Bow Tie Boys had something to worry about. That V8 Mustang was now a box of chocolates. Listen closely. Very closely. What is hidden upstream of those mean sounding Flowmasters? This heavy convertible could be a 16-second slug or a unibody-bending 10-second Race Wars Champion.
Blue was anything but the feeling of the oval fans in the first half of the 90’s. In 1994 Ford radically changed the design of the Mustang but it retained that magical 5.0L. Until 1996.
A New Era
Other than vertical tail lights and wheels and fender badge, the 1996 Mustang GT looked identical to the 94-95s. But under the hood, Ford replaced the proven pushrod V8 with a 2-valve, SOHC (single overhead cam), modular V8. Nobody knew what to make of it. Displacement was reduced from 5.0 to 4.6 but horsepower was about on par with the outgoing engine. First impressions of the 2V SOHC 4.6 were commendable. The Mustang GT’s power plant was now smoother and seemed to beg for RPM.
But things weren’t all green. The 2V SOHC 4.6 engine made great exhaust notes however making horsepower was a big problem. The engine was simply anemic. It ran out of steam quickly on the top end and that’s just the beginning. Tuners quickly poked holes in the engine’s design. Ford used fragile hyper eutectic pistons which were not detonation friendly and discouraged forced induction. If boost was added the next concern became the cylinder-head fasteners head gaskets. The intake manifold was made of brittle plastic that was known to crack and leak. And yet we haven’t touched on the biggest power restriction of the 1996-98 2V SOHC 4.6 engine – the heads.
I won’t bore you with the combustion chamber cc’s, cam lift and profiles, but in short the heads on the 1996 to 1998 Mustang GT were paper weights literally holding the engine back from producing decent power. Even with a supercharger, this engine struggles to put 300 horsepower to the ground. The meanest sounding 2V in the world won’t run more than a 14 second quarter mile without forced induction or serious weight reduction and slicks.
But all hope isn’t lost for the 1996-1998 Mustang GT. Ford redesigned the engine in 1999 and power increased to the tune of 260 ponies. These engines became known as performance improved, or PI, and it wasn’t long until we discovered the heads and cam would swap over to the older 1996 to 98 performance starved 4.6. Owners can expect something along the lines of 30 horsepower and 40 pounds feet torque and a bump in compression ratio.
The head swap has become more popular in recent years but the bang-for-the-buck isn’t great nor is it an afternoon job. Unless the owner is completely Gung Ho about their 96-98 Mustang GT, chances are it’s just a loud turd.
//Follow Josh on Twitter @JoshTaylorUSA
Josh’s first three cars were modified Mustangs. He spent way too much time at performance shops, drag strips and autocross courses until giving up on the FOX/SN95 platform and heading for greener pastures.