Good start with the engine. ON a budget first off, as dpk83 said exhaust, heads and KN pod filter (or similar). Next advance your timing. With PULP and an increase of my base timing to about 16 degrees, I got an extra 12kW at the wheels for my EBII MPEFI engine. Not to mention great economy with the engine able to breath.
These engine love a big Cam some I told, so try throwing in a big cam. Crow cams have kits you can buy (for lots of dollars) with the cam and Mod chip for the fuel and ignition map of your ECU, but I donít know about the CPI. Personally with my EBII, I went for a Stage 3 Crow Cam, but I had a wolf3D computer as well. It made good power, 158rwkW.
Give that a go!
Just a EBII I6 GLI with lukey extractors, 2 1/2 inch exhaust, K&N filter, malpassi Fuel regulator, Wolf 3Dv4 computer and stage 3 crow cam with vernier gear. ""158 rwkw""