| The piston-bore clearance is a bit more related to the kind of power output you expect to produce with the setup. I have always recommended 0.003" PB clearance for the Wiseco pistons. Not sure if you are aware of this or not, but the original Wiseco pistons suffered horribly from rattle which was a result of an incorrectly designed piston. Wiseco stopped production of their pistons due to these issues and I worked with their main automotive engineer at that time, Brian Nutter, and redesigned their pistons. I installed the redesigned pistons in my personal Z late 2003 and ran them through the rigors for ~1500 miles - no rattle - good performance. The recommended PB clearance at that time was 0.003", which was a bit conservative for a mildly modded ZTT. The thing to keep in mind is that the more torque you produce, the more heat the piston will experience, thus the more expansion the piston will experience during operation. One needs to ensure that the piston never reaches the bore diameter during its expansion, for obvious reasons. In my personal ZTT, which is producing ~700RWHP and ~640RWTQ, I am running at 0.0038 clearance and haven't had any issues with it. Even when cold I cannot hear the pistons when it is free-revved. My recommendation: For setups producing up to 500RWHP, give yourself 0.003" clearance. At 600RWHP, step that up to 0.0033-0.0034" At 700RWHP to 1000RWHP, give yourself 0.0037-0.0038". I doubt you would ever need to exceed 0.0040" for non-nitrous setups. If you are running nitrous, you should add a couple more ten thou to the numbers above to accomodate..
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