LF3 vs LF4?

[GTANotch88]

What are the main differences between the v-sport LF3(2014) and an LF4 engine?
I might be buying a cts v sport and I'd be interested in doing some mods but I was wondering how different it is from the atsv/ct4bw engine. I assume turbos, tune, and non-special rods. Is there anything else?
As soon as I started considering the car, I checked tapout's site for possible mods.

 

[WONT TAP]

The primary differences are that the LF3 has smaller turbos and different connecting rods.