I had 2 escort gt's with the 1.8 - I hit the rev limiter countless times every day, neutral dropped it almost as often, street raced it every weekened, and took it through the mud more times than i should have... and this was with over 150k miles on each. Shit, i even dumped it from 7200 into reverse to make it do backwards wheelies every few days for laughs. There were countless times that ahem, my friends, would take it down the highway, putting it at 7200rpm in 4th gear for good amount of time, and the engine only wanted to go again afterwards.

I could not have treated those 2 cars any shittier if I tried. On one of them, I cut the exhaust off at the header and advanced the timing by ear, which was probably way too much. It never smoked, it never stuttered, it never broke. I'm not joking when I say that it's one of the toughest engines I've EVER fucked with.

300hp on a BP with the stock forged internals should be no problem, it's been done a thousand times.

edit: and a v8 swap would just kill you, or at least make you go broke. you'd need a new engine, tranny, mounts, new modded rear end, etc. it's a wonderful idea, if you want to die broke.