I haven' still made my mind what kind of engine will find it's way to the engine bay. Somehow I like the nostalgic feeling of the "orginal" 2-syl aircooled engine. I have already bought 750cc kit and panda head from Ebay. That would be easiest and maybe also the "right" way to tune 126. I have still about 2 months to think about this before I continue building my 126.
I have also planned two other realistic options for the engine:
1. "Orginal" 2-syl aircooled engine supercharged. That would need programmable ecu (Megaquirt or similar) and quite a lot modifications to make it work reliably. This option would add a alot fun factor but I don't know how reliable it would be as that is very important for me in all my cars.
2. Cinquecento 0,9l engine with Megasquirt. I have studied a alot which 4-syl engine would be possible to put there and seems that Cinquecento 903cc is the only Fiat engine which is possible to swap according Finnish law's..
I think that with this option the engine would be VERY reliable and there would be a alot potential to tune the engine afterwards.
As a big negative aspect is that the nostalgic feeling is gone after that engine.
I have had quite contradictory feelings what this car will be. Roll cage and hardcore engine modifications would be now quite easy to do as the car is just a shell, but I don't know if those would be " not so good" idea as a long term. Orginally this was supposed to be just a restoration and maybe some small mods. Now it's so close that this will get out of control or "moped starts to do wheelies" as we say in Finland.