Looking to rebuild a 1.0L engine? Sweet! Exhaust valves burning are a common problem with these cars. Most mechanics consider them "Disposable" and off they go! Well, these cars are so easy to rebuild! First off, remove the head and either send it off to a machine shop or rebuild it yourself.............
1.0L Head Repair Guide
Detailed 1.0L head rebuild guide
Burnt valves are a common problem.............
Stainless steel exhaust valves will last forever and are cheaper than crappy valves if you get them from
3Tech Performance. So either you rebuild the head or have the rebuilder use the stainless valves.
If the car has over 100,000 miles on it, you may want to consider rebuilding the bottom end...........
Bottom End Rebuild Guide
It's only a few hours extra work and well worth the trouble. You can also check the bottom end first if you don't want to rebuild it by pouring solvent or gas down the cylinders with the head off and check for leakdown............
More detail here...........
Mrs. Mullet's Extreme Metro Makeover
Boring out the cylinders will not gain you any MPG and will not be needed unless there is cylinder wall damage or other major issues. After rebuilding the engine, if you have a 1996 model, I suggest using at least a 10 degree timing gear from 3Tech for better power and economy. If you do not drive the interstate and do a lot of city driving, I suggest also getting the economy grind camshaft from 3Tech.
If you drive highway speeds, then you need just the 10 degree cam gear and consider a trans upgrade. A manual trans from a 1.3L Metro has a higher gear ratio and will net better highway MPG's. Aeromods will also increase highway fuel economy.
Good luck with your project!