I'm not too familiar with inline engines. I've only rebuilt v6's, and thier are many differences. The only thing I can think of that would really make a difference would be a Paxton Supercharger. Paxton's tend to be on the expensive side though. Turbo would be the only way to go with a 4cly in my opinion, but then again, I'm not too familiar with anything other than the 2.8 and 3.1 v6 family. Tell me if you find anything that makes a massive difference.