I had a pretty tasty Fiesta when I was younger.
A 1982 Mk1 XR2 which I put a 2.0 lt twin cam Lancia engine in. ( the only good thing from a Lancia Beta !! ).
With the extra weight of the motor and the smaller rolling radius of the Fiesta,s tyres, it was pretty quick.
My rally driver mate put a rwd 2.0 lt Cosworth engine in a MK3 Fiesta. That was really fast off the line. He still never reckoned he could get around the stages as quick as he could in his old MK2 Escort.
Del.
While I,m at it.
Of all of the fast, " boy racer " cars I had, the Renault 5 GT Turbo was the quickest by far off the line.
I had mine boosted and fuel adjusted and boy was it fast. If I remember rightly, I think the standard 0 to 60 was about 7 secs ?.
But I think the all round " fastest " was a Series 1 Escort RS Turbo. ( MK3 Escort ). Bigger intercooler, " chipped ", hybrid turbo. It used to spin the wheels in 3rd gear if I was,nt gentle with the throttle !
Thats were its problem was, traction. ( well one of its problems along with torque steer, body flex, poor weight distribution and corrosion ! ).
Its true what they say about 200 bhp in a front wheel drive car. ( they say its too much by the way ! ) I dont think my RS was anywhere near that.
Confession over.
Del.