I've got a 2.0 type4 fitted with a single twin choke weber conversion. Starts up fine but when it's hot develops a huge flat spot. The previous owner has gaffa taped up 90% of the air filter so I'm guessing it's jetted wrong. Anybody ever taken the trouble to find out the correct size jets for these things? Ignition system is spot on and there's no air leaks by the way. Any help greatly appreciated.
