Castrol Mk II
If at first you don't succeed, just start again with a much simpler idea. Buy another two door Allegro. Acquire a manual six speed, 6.3 litre stroked V8, 1989 C4 Corvette (one careful owner, 40,000 miles), which just so happens to have the same wheel base as an Austin Allegro (really it does); strip the Corvette back to basics (and then a bit more), find a genius with a welder (big shout - aka Simon at Suffolk County Manta's); do some jiggery-pokery, eat some chips, do some more jiggery-pokery and bob's your uncle. One V8 Allegro - now in primer - and soon to be deafening pedestrians (and the occupants) in a town near you.