A down pipe and a stage 2 tune will get you about 30hp
If you add a 3" exhaust to that, add another 10hp.
My wagon has a 3" DP, stock midpipe, a little head work, tuned at 21psi and makes 280whp.
226,000miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
Engine Build - Click Here