anybody know where you can buy performance cummins crate engines  

You mean simply getting one as a hotswap, and not using your own?

I've not heard of any places offering this, more likely due to the cost involved.  Most places offering rebuilt engines for performance usually start with your own engine and will pull it, do the work, and drop it back in for you to make sure everything is running right before it leaves their shop.

You might send a few e-mails out to those companies that do performance engine builds to see if they offer it.



Kris