Skip the auto shop - Our mechanics make house calls

Q: What happens if i replace the catalytic with a thrush muffler and put a DC sports exhaust about 2 feet away from the thrush.

asked by on

What happens if i replace the catalytic with a thrush muffler and put a DC sports exhaust about 2 feet away from the thrush. Will this sound bad? Will it make a difference on the HP and Gas mpg. Thxs

My car has 200000 miles.
My car has a manual transmission.

Removal of the catalytic converter on a car that will be operated on the street is very illegal, and can get you a huge fine from the EPA. Also, since most modern vehicles are designed to run with some system back pressure, you may actually notice a decrease in performance, due to the way exhaust flows out of the manifold and through the system.

The vehicle will certainly be louder, and may or may not sound better, depending on who’s listening. Generally small displacement four cylinder engines with an almost completely free flowing exhaust are a love it or hate it sound.

However, I stress again that this is illegal to do, unless you plan to operate the vehicle off public roads only, such as on a race track or for off road use. If you want to increase the performance, it’s best to do some research and decide which exhaust system and high performance catalytic converter would work best for your vehicle, and go with those parts.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  • Home
  • Questions
  • What happens if i replace the catalytic with a thrush muffler and put a DC sports exhaust about 2 feet away from the thrush.

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Ignition timing out of sequence.

Hi there. First you would need to know the firing order for the electronics on the distributor. The distributor number one on the firing order is the terminal on the right side at the front of the vehicle. Since you...

Q: What years ignition module will fit my 1991 Chevrolet Silverado 5.7

Hi - GM V8 ignition control modules from 1987 to 1995 should interchange with your '91 5.7L. For assistance, I recommend a ignition control module replacement performed by a mobile, professional mechanic, such as one from YourMechanic, who will come...

Q: I don't know if I have two mufflers or one if I do have one what does the other one do ? Thank you.

When you look under the back of the car and you see only one pipe out the back then you have only one muffler and a resonator. The resonator is near the back and is used for lowering the exhaust...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...