I have had my Bosal Catback for about 3 weeks now and have noticed that torque in the powerband from 45.k - redline seems to completely dissapear. It revs faster probably because it is less restrictive but I might as well shift at 4.5k because there is no more power after that. With the exhaust, it feels like I have less power than before. Maybe I'm just trippin' but the exhaust in my opinion is not worth the $400. I get more noise but nothing to show for it.

 

Your statements contradict each other. Since it revs faster from 4.5k – 6.5k, then there has been an increase in HP. HP is a function of torque and engine speed. Since you are looking at the same section of engine speed, then torque has increased. Assuming your test was performed under similar conditions (same gear, flat road, ect.).

Losing low end torque, however, is common when upgrading exhaust systems. Get it back with forced induction or higher compression.

 

I noticed the same thing with the exhaust I just installed. It actually seems as though it revs much smoother now, but from the seat of the pants, it seems a little bit less of a surge of power. I think that it actually is going faster, but because the engine isn't quite as strained at higher rpm's due to less restriction, it feels smoother and therefore slower. Notice how in a car that's straining, you feel like you're going fast, but in a car that's smooth (like a Mercedes), you can be going a lot faster and hardly even tell. Also, the torque is going down after 4000 rpms. Remember, Horsepower is a function of torque at a given rpm. you may have less torque, but you're still making more horsepower.

 

Scarmiglio, I think you hit it on the head. I was thinking the same thing about the noise and the engine not straining... The car does rev a lot smoother and seems to rev quicker. I still find to shift at 5500 proves the best point. How do you like your exhaust? I met you at planet performance one time and may be back soon to get some more stuff. Thanks for your response.

 

I like the exhaust a lot. It's barely louder than stock, but much smoother acceleration. It adds a touch of rumble off idle and get a little louder as it revs, but it's nothing that will turn a cops head. I can't even hear it with the radio on. At cruising speed on the highway you wouldn't even know that it's there. It looks great too. It perfectly fills the indent in the rear bumper, and the tip is double walled so it won't discolor.

By the way, I remember who you are. Check your pm box.