I've searched all over the 'net and can't find the info I'm looking for. I'm trying to find out the technical differences between a C15 and a C18. There's the obvious stuff I picked up from Cat's website, bore and stroke and whatnot, but nothing more detailed than that. What I really want to know is whether I can use C18 internals to upgrade my tired old C15, the classic hotrod trick of boring and stroking an engine, just on a wee bit bigger scale. There isn't a significant difference in physical size between the two engines, but that doesn't necessarily mean they're at all compatible. Anybody know?  

I would not think anybody around here could answer that but have you tried around CompD  

What's CompD?  

I'm willing to bet Bruce would know, he's one of the few guys who hot rods big rigs....

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