I have an I30, I have an intake and recently got a universal muffler ( HP racing) of e-bay for a hundred bucks. I went and got it installed. They had to do custom work on it. The put a curved pipe to extend it a little because it wasn’t long enough. When I tried to see if it got any faster, I was very disappointed. The car didn’t accelerate that fast, in fact it slowed down. If I floor it I didn’t feel the same acceleration as before. And I don’t hear my tires “squeak” Why? What’s wrong? Was it because it’s a crappy exhaust? I also discovered that the there is a little leak where the guy soldered the pipe, is that why?

 

A lot of Autos when they change things like Exhaust or Intake notice a low end loss. That may be your problem right there. The exhaust leak your talking of wont help any either.

SuDZ

 

low end loss cause u probably got bigger piping, you will get more high end now ( you lost the backpressure)

 

What type of intake you running? That will determine how much loss you will lose as well. A CAI for instance will give you more low end loss than a cone filter. But the handoff as pointed out is at the top end.

SuDZ

 

You also got to understand when you install an Muffler that is a straight pipe inside (u can look inside the muffler and use it like an telescope),,, U dont have any back pressure... so that means you are going to loose your TORQUE ,,, but maybe MIGHT gain a little horse power.. but notting to bragg about... oh and also make your car louder. IMHO the car is slower. That why when you run a muffler always get an aftermarket exhaust the SPECS for your vehicle. IF not... your car muffle investment would be poo poo.