[War_Wagon]

Have you removed the silencer from the air intake airbox? They are fairly restrictive in those cars.

Also, keep an eye out for a used aluminum drive shaft for it. They are popular with the 5.0L Mustang drag race crowd, so you might find a used one cheap somewhere. I am pretty sure that your style Mustang uses the same shaft as the earlier Fox bodies, but you might want to double check. We put one in my friends '86 GT and not only did it save weight, but the reduction in rotational mass actually made a noticeable difference in acceleration. Not huge, but you could feel it.

And check your timing, those cars were supposed to be set at 8 degrees advanced from the factory, but we have found a lot of them that were at 6, and one that was at 4 from the factory. Up to 10 degrees advanced still runs fine on 87 octane, around here at least, YMMV.

An aluminum radiator / electric fan set up is another used hi-performance part that you may be able to find cheap, saves weight and cools better, and swapping the electric fans in takes mechanical load off your engine.