Ok, next installment!

The new blower works perfectly so after running it in I'll convert it! Now for the 25cc; I have just stripped it and found the following; 1- It would't run on Gas and standard ignition as the cylinder head had completely cut through the ignition lead! 2- The detonation was caused by a leaking base gasket leaning out the mixture. The engine is actually in remarkable condition considering the fact that it's at least 15 years old!!! There are no scratches on the barrel or piston and no signs of damage from the detaonation although the piston does show signs of ring blow by. The crank, big and small ends have no play and the bearings rotate smoothly. There doesn't seem to be any weeping from the front seal, so all in all a good useable engine. Now for the questions;

Does anyone know why there is a small square lump on the top of the inlet and if I remove it will I need to pin the piston ring? Also the engine is fitted with a Zama CIU H11E carb. Can I use this carb on my 30cc? and is it any good for aircraft use. Can I cut down the inlet manifold so that the engine fits in my cowl or will upset the inlet pulses etc.

Oh in case anyone is interested, this engine as is, with ignition, carb and exhaust weighs in at a hefty 4lb 10oz!!!!! Better get the dremel out!

Thanks

Rich