Tuning 1272cc GF

I want to fit oversized pistons to my Driver, (and yes i want to keep the original rev happy engine!) does anybody know what piston size i can go up to? haynes say 75.98mm (from 75mm) but id like to go a bit further say, 77/78. also does anybody know of a VW crank i could use to increase the stroke of this engine?

Not sure on the pistons but you'll affect revving capability if you change the crank

it doesn't matter as i will be lightening and balancing the crank to retain its revvy nature! anybody? does the 1.6 crank fit?!

just done a quick search on google and wikidpedia details the engine's from that era as the EA111 engine's so I think the crank's are possible interchangeable! here's a link

http://en.wikipedia.org/wiki/List_of_discontinued_Volkswagen_engines#50-75_hp_1.3

ya know what i think i got that wrong lol its the engine below called the EA827

Using that data the 1.6 crank has a longer stroke so your 1.3 pistons will come out of the top of the bore by 3.3mm - 1.6 pistons will be too big as the bore is 4.5mm bigger.

Whaterver you do you'll be raising the capacity which will affect the revving capability - not by much probably but noticeable.  You'll probably end up with a 1.5 engine (1457) so might be worth starting there.

Cheers

Rich