I know exhausts are mainly for sound and looks but have read they do add a little HP around 5-10. I know I won't feel this, but I'm wondering is there any proof. Any tests that show an axle back only (I have awd) add HP? And which ones add more? I'm particularly interested in the tanabe medalion

 

The added power usually on the top end. In some cases, the car actually lost power at the lower end (or in the normal everyday driving ranges). Unfortunately some of us equate the added noise and vibration to gain in power.

 

Yes it adds HP. There is an official thread about different branded exhaust that actually been dyno tested by its owners and post status, and another thing is Tanabe was on the fastest IS350 on the drag strip by a clublexus member.

 

But but you will not notice any difference since it is so small.

 

Thanks guys. Some additional searching and I found this thread from 2006 which has dyno results on is250 on page 2 https://www.clublexus.com/forums/per...is250-rwd.html

 

You can replace your factory system with an aftermarket cat back.

It looks better
Sounds meaner

But wont do anything as far as performance because the power gains are so minimal. You cant actually "feel" 2-7 hp.

 

+1 on meine96ws6, it is only for sound and look.

I actually "FEEL" the car being "SLOWER" because the added sound doesn't go with the added speed lol. May be it is just me lol.

 

It will add a little bit of HP but not as much as changing the whole catback system. Most of it is in your head that your car is faster by changing just the axle back maybe because it sounds louder.