I have installed a HKS up pipe and a Tanabe Ultra Medallion cat back exhaust on a 2004 WRX. Ran at the track and couldnt do better than a 15.3. I ran under that in my civic si. No exhaust leaks before or after the turbo. Is the cat back exhaust the cause for the feeling of power loss from 2500 to 5000. Any suggestions for the next step. I need more power captain.

Is the cat back exhaust the cause for the feeling of power loss from 2500 to 5000.

What power loss? These engines don't have power until 4000. Try driving in the power band and see if it gets better.

wrong forum. this should be in the Factory 2.0 Turbo forum.

i don't see how adding the upipe and cat back could have made the car slower. Are you using the stock downpipe? If you are then i wouldn't expect any noticable gain from those mods. You're still choked after the turbo...

wrong forum. this should be in the Factory 2.0 Turbo forum.

i don't see how adding the upipe and cat back could have made the car slower. Are you using the stock downpipe? If you are then i wouldn't expect any noticable gain from those mods. You're still choked after the turbo...


As mentioned above. Don't expect big power gains from an uppipe and catback exhaust - without upgrading your downpipe.

A good question would be what did your WRX run stock? Also let us see what your time slip looks like. If your running slow 60' times, that would explain your slow 1/4 mile times.

I've seen guys with stage 4 WRX's (270 whp) run 14s in the 1/4 mile. So its not always the car. In most cases its the driver.