The turbo coupe is a lot lighter than the SC. The 89-97 mn-12 chasis tbird is about 3800 lbs w/o driver and no luggage, empty gas, with a 5-speed. The auto's were heavier, plus if you get options like moonroof, and stuff. I took the spare and jack out of mine to help lighten up the load. The gears really helped it feel lighter.
The 2.3 turbo is another motor ford choked off at the factory. Just by increasing the boost with a simple home made boost valve it feels like a different car. The mods are similar to those of the turbo buicks, bigger down tube and exhaust, larger turbo, port and polish head, bigger valves. more aggressive cam, gears, slicks, and I'd get a 5-speed TC so you can launch with boost. I've seen a couple in the 11's with the 4 banger. They are on the fox chasis like the mustang.
Another thing, about the head gaskets on the 3.8L SC motor, anytime you use an iron block w/ aluminum heads and throw boost into the mix, you will have issues. Mine lasted 182k miles on my 90 SC. I did the repair myself, instead of paying someone $1500 for the labor. I spent maybe $400 for parts, head milling, ported and polished mildly done in my garage. I also bought all new hoses, belts, cleaned up everything that came off, painted everything, (pullies, brackets, supercharger, throttle body, intercooler tubes, intercooler, etc....)
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