Which is the more tunable Felicia engine ?? The 1300 or the 1600 engine ? And which has more available parts ?

I would be looking to carry out head work and cams etc .

I'd say the 1600 has more potential as it is a VW engine and would have had more parts developed for it.

do a bit of research for them both before making your mind up.

but it still has the skoda gear box non? can this handle it?

Go with the Skoda engine. The VAG1600 is a cambelted boat anchor, not a light and revvy chain driven motorsport lump. Just remember, within VAG, who got to design and build the new small engines? Skoda have always done well at that.

do like the meatball says. 1.6 is relaible like a tank but the 1.3 is the rally derived alloy headed motor with cams, ports, pistons et al desgned for it and power will soar over the 1.6 for skoda money rather than vw money