I am guessing we have forgotten Ford own attempt at this same sort of thing. lets see, 390 and it anemic 360 clone, 302 and the ever popular 255, and our own 2.3 Ranger 2.0 turd. All were based on proven powerplants, Ford tried to make a more effeciant alternitive and ended up with less power, poor economy and less durability in all cases. Another example is the Lincolns and other full size cars of the late 70's. Had a 460 or the optional 400 for engine choice. Well of cousre the thing to do was get the smaller engine to save fuel. Wrong, too little power for weight of car, overwork the 400, economy goes away and engine was short lived.
Not trying to reopen this can of worms, but those cars are huge. The car I am talking about is an lx hatch fox body. I doubt not having enough power to pull it's weight will be a problem like it was in your other examples. Reguardless, the mustang is in the back yard now, and I think of it less and less everyday as my T-birds makes me fall deeper in love. So pretty much once everyone stops responding to my posts I wont have any reason to make more, and you can all be free of me for at least another year, so let's let that happen shall we? PEACE
I had a 400m in an F150 and I thought it was bulletproof. Got 15 mpg one day also! Got it with 140k miles, drove it 50k and sold it running as good as the day I got it. Actually a really good engine, just never became popular as a performance engine, being overshadowed by the 460.