I am not using the .18 head and am having no problems, but I also used a little bit of copper silicone sealant on the head shim and on the underside of the sleeve. On the old Wildhobbies forum their also was a few people that did the .18 conversion and are using the stock head with no sealing problems.
A comparison would be great. The O.S. engine will have more top end but I am not sure about torque.


rolland