Hi! Here's a video with English subtitles about an engine upgrade I made while ago, from 1.2 8V to 1.4 8V. I used 1.2 8V cylinder head for now because Grande Punto already has VVT (variable valve timing) so there's different camshaft and that's why camshaft position sensor is also different. Plan is to modify the 1.4 8V camshaft to be usable because the 1.4 8V cylinder head has slightly bigger valves (usually means better flow = more power). Combustion chamber and piston crown are also differently shaped. My 1.2 8V cylinder head is already ported and flows about 15% more than original so the gain may be minimal though. But of course I will port that also!
So to the other differences:
1.4 8V has 200mm clutch, 1.2 8V has 180mm (mine was upgraded to 190mm from 1.2 16V). Those engines have different flywheels and clutches so you have to use both from same engine. My clutch was worn out so I used the 200mm clutch & flywheel and it's working fine.
Other thing is ignition. The ignition is one tooth out from crankshaft if you timed it correctly, because of the VVT I believe. It has 23 tooth so ignition is 360/23=15.6 degrees retarded. Crankshaft pulley, where the 60-2 trigger wheel is, is the same so there's no point changing that. So there's two choices, use the 1.2 8V crankshaft sprocket or drill new holes to crankshaft pulley. I chose the later option. I used the alignment pin as my guide, 15 degrees is about 5mm at that point and of course you need to drill new holes for the three bolts also.
And the results:
Power difference is huge! It's under 20hp in paper but you can definitely feel it. 1.2 8V was struggling to go uphill with my 500kg audio system, but now with 1.4 8V there's no need to change from 6th gear. I had to use 3th gear sometimes so it was really struggling, the difference is hard to believe. Of course the 1.2 8V was about 100000km more driven so that can have something to do with it. And yes I have also upgraded to 6 speed gearbox from Fiat Stilo 1.2 16V and there's a video about that (and lots more) on my YouTube channel JoniK
So to the other differences:
1.4 8V has 200mm clutch, 1.2 8V has 180mm (mine was upgraded to 190mm from 1.2 16V). Those engines have different flywheels and clutches so you have to use both from same engine. My clutch was worn out so I used the 200mm clutch & flywheel and it's working fine.
Other thing is ignition. The ignition is one tooth out from crankshaft if you timed it correctly, because of the VVT I believe. It has 23 tooth so ignition is 360/23=15.6 degrees retarded. Crankshaft pulley, where the 60-2 trigger wheel is, is the same so there's no point changing that. So there's two choices, use the 1.2 8V crankshaft sprocket or drill new holes to crankshaft pulley. I chose the later option. I used the alignment pin as my guide, 15 degrees is about 5mm at that point and of course you need to drill new holes for the three bolts also.
And the results:
Power difference is huge! It's under 20hp in paper but you can definitely feel it. 1.2 8V was struggling to go uphill with my 500kg audio system, but now with 1.4 8V there's no need to change from 6th gear. I had to use 3th gear sometimes so it was really struggling, the difference is hard to believe. Of course the 1.2 8V was about 100000km more driven so that can have something to do with it. And yes I have also upgraded to 6 speed gearbox from Fiat Stilo 1.2 16V and there's a video about that (and lots more) on my YouTube channel JoniK