In terms of dollars spent for performance gained I think the tune should be the first thing added.
I got an Ecutek etune for my stock 2013 Z 7AT. That by it self increased power and fixed the throttle response issue. Then I installed the following one and time and noted a performance gain with each addition.
HR upper intake plenum (M370)
Turbo XS cbe
FI Rhfc
I have data logged after each mod and found that the afr's are still right on the original tune.
__________________
Ecutek | DIY HR350 upper plenum | DIY ported lower manifold | TurboXS cbe | FI rhfc
|