sorry for butting in but this is the first message that has caught my 
attention.  I have both the O.S. CZ-Z and Thunder Tiger BZ .12 for my RC10GT 
and I'll give you my opinion on the CZ-Z (I haven't run my Thunder Tiger yet 
because of the snow outside here, but I can't wait) The CZ-Z is a big waste 
of money because the piston and sleeve wear out really quick, on mine I had 
to replace it after 3/4ths of a gallon of fuel, after that it's another 40 
bucks added on to the 140 I already spent on it.  The reason I bought the 
Thunder Tiger is because it is supposed to be a TRUE ABC engine unlike the 
CZ-Z.  From what the instructions say about the ABC construction it says that 
when the engine gets hot the piston expands which makes the engine last 
longer. Personally I didn't like the O.S. CZ-Z it wasn't as great as everyone 
says and it's definatly NOT worth the money in my opinion. 
--- InterEcho 1.16
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