99 Trans Am. I cut off the stock exhaust yesterday. I cut it just before the muffler, so the pipe actually comes to the rear axle and stops there. Its loud as hell without the muffler but what I would like to know is did I gain any horsepower by doing this? I was told that I would, but it almost feels like its slower than before i cut off the muffler.... maybe its just me. anyone know?? by the way, my car is not a WS6. just a reg TA

 

Yes you probably gained a few HP, but why did you not get a cut-out instead of just cutting the whole thing off? If also probably feels slower because running with "open exhaust" you lose most of your back-pressure and therefore you would lose acceleration/torque but would gain more top-end power.

 

Dont listen to the ricer argument made in the previous post. You didnt lose any power. Back pressure is always a bad thing. Period.

 

Ricer Argument? I know it's true, because every time I open my Q-tec's I can feel the shift in power. It's "slower" in acceleration and pulls harder up top. Period.

 

If there's any power less at all, it's not because of loss of backpressure. . Backpressure kills flow AND velocity. The two things you need to make power.

 

And where do we race? I don't know about you, but I'm not racing under 4000 rpm.

Forget low end power, my car doesn't have anything under 4000 rpm.

 

Ok, than why does it pull harder from a stop when I run it through my full exhaust, and slower when I run open headers.

Kain, I see what you mean about the the low-end power. But why can I feel such a significant difference?

I guess I may have some learning to do.

 

It could be purely psychological, being that it is so much louder now and theres not THAT much of a difference? Your butt-o-meters arent always accurate