Fox bodies by 87 were 225 horse in that small body alot of fun and squirrely. These cars were the return of "clean" emissions compliant fuel injected performance. Alot of what happened to horsepower in the 70s was purely emissions mandated. In the mid 70s, the best car was the Pontiac Trans am. 400 CI . 77 Bandit Trans Am- 185 Horse . 85 Mustang GT- 210 horse 86 -200 horse 87- 225 Horse. Those Fox bodies were a breath of fresh air compared to what was previously offered. IMO its not a comparison of Fox vs 340 A body its more a comparison of eras. Early 70s vs mid 80s. In each era, both cars held their own. I do believe the 340 A is faster in stock form simply because it has more Horsepower. The Mopar is more user friendly as far as day 2 mods.