They're good platforms. I had the option of buying a fox body (87-93) but went with the 94/95 5.0's for a few reasons.
And no swaps. They GT's and some of the Lx's came stock with the 5.0's. You wouldn't have to deal with swaps.
Fox 5.0 potential and pros.
*They're cheap
*have the best aftermarket of any modern day v8/domestic
*Lx's 5.0 comes in at around 29XX-31XXlbs depending on options making them fairly light for a v8 equipped car. With some aluminum and fiberglass aftermarket components the weight could go down farther.
*ran mid 14's stock which is pretty darn good for a 15 year old car equipped with loong 2.73 highway gears. A few bolt ons and free mods can put you into the 13's for cheap.
* easy to work on and relatively cheap to fix since parts are readily available and easy to find. You can't go to a parts store without tripping over 5.0 parts

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* They've got arguably the best sounding exhaust note of any small block v8. Even when stock, they sound mean. Throaty rumble is always music to the enthusiasts ears.
* the stock motor isn't really built to it's true potential. In it's restricted state, it produces 225hp and close to 300lb-ft of tq. Witout stroking or forced induction and by just changing the stock components within the engine(heads, cam, intake, exhaust, etc...), power can go from 225hp to over 400hp N/A.
* They can be stroked out to 355ci from the original 302ci. 500hp+ N/A potential without Forced induction. 331 and 347 stroker kits seem to be very popular. Guys in the NMRA have made 2000+ horse with turboed/Supercharged 347's.
* They have a low compression ratio and the early 90's come with forged pistons which makes them FI friendly. But 12psi would be the limit on the stock engine.
* Every means of Forced induction is available. Turbos, Twin turbos, superchargers, Nitrous. They show consistant 100+ hp gains. For example, it isn't uncommon for a STOCK 5.0 with a proper TT kit to belt out close to 400rwhp. A gain of over 200rwhp!!!!.
* you can do a 351 or a big block swap which gives you the potential for more growth. The 351 can be stroked out to about 426/427ci. The big blocks to over 500+ci. Some good numbers if you're really serious about drag racing.
Cons:
* rear drum brakes except on the 93 cobra(which is why i went with the 94+ which had 4 wheel disc)
* weak T5 transmission. With serious mods, you'd have to upgrade or rebuild it to handle the Tq levels the engine would be making. Expect to pay $1,200 for a good strong new 5spd aftermarket tranny. You can spend the extra $$$ and go for a 6spd if you so desire.
* insurance can get expensive depending on age, driving record, and location.
* you'll be making more trips to the gas station compared to a civic. But peformance never equals economy. Just look up the mpg average of the supras, m3's, porsches, NSX's, etc...
Hope this had been some help to you

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