Say if my code is always going to be run on a particular processor and if I have this information during installation - is there a chance I can avoid JIT?
Use NGEN:
The Native Image Generator (Ngen.exe) is a tool that improves the performance of managed applications. Ngen.exe creates native images, which are files containing compiled processor-specific machine code, and installs them into the native image cache on the local computer. The runtime can use native images from the cache instead using the just-in-time (JIT) compiler to compile the original assembly...
For additional information on using Ngen.exe and the native image service, see Native Image Service...