removing catalitic converter

[redbull660]

I know it is illegal, but has anyone ever completely removed the cat. converter and went with high flow mufflers. I have a 99 v10 and would like to try this. Will it hurt my 02 sensor. And what will it do to my mileage. thanks

[WhëëlMå1]

Especially on the new computer controlled vehicles, they can cause more harm than good. The sensors do not read correctly, which in turn cause the computer to compensate. That compensation can often times give you less peformance. The ideal solution is to swap in a high flow catalytic convertor. What state do you live in? Emissions testing? Visual inspections? Have you thought about resale value?


Rich

[redbull660]

we have no inspections here in montana, but I think I will leave the stock cat alone, especially if it will mess up my computer and sensors.

[WhëëlMå1]

If you want performance, I would go with a high flow cat. I have one on my bronco (along with high flow Y pipe), and I passed the sniffer test here in MA no problem. It hasnt set any codes either, and its been on about a year now.


Rich

[boxcar1974]

Moving to Montana.........No inspections!!!!!!!!! Here in Massachusetts we cannot touch our exhaust at all!!!!!!!!!!!!

[victorcharlie]

Originally Posted by boxcar1974

Here in Massachusetts we cannot touch our exhaust at all!!!!!!!!!!!!

That's not what the Massachusetts supreme court said!

[WhëëlMå1]

Have a link or something to elaborate?


Rich

[boxcar1974]

4.04 (b): Procedures for Inspection of
Non-Commercial Motor Vehicles
(5) Muffler and Exhaust System. Accelerate motor to test for prevention of unnecessary noise and emission of any unreasonable amount of smoke. The exhaust system, exhaust manifold(s), exhaust pipe(s), muffler(s), and tailpipe(s), if designed to be so equipped, shall be tight and free of leaks. System components shall be securely fastened with fasteners in place and undamaged. All motor vehicle exhaust systems shall discharge the exhaust beyond operator, passenger, and/or trunk compartment. Unnecessary noise is herein defined as any noise which is louder than that emitted by the vehicle when equipped with the original manufacturer's equipment. A gas or diesel vehicle will be rejected if, at normal operating temperature, at any constant speed over 15 MPH, (approximately 1,000 to 1,200 RPM's) visible black or blue exhaust emissions are evident

This is from www.vehicletest.state.ma.us under the regulations section. You cannot increase the noise emmission over the stock system. So basically you cannot touch it at all!

[Voksboy]

I've removed my cat completely. Modified and returned the sensor and no problems. I lost a bit of torque but gained high speed. After about 6 months I decided to put my cat back. Oh you have to put some kind of silencer if not, it will be really LOUD

[frdstpsd98]

Thats all chinese to some people. All you have to do is run O2 sensor foolers, find someone to print you out a sticker without testing the vehichle, and you can make it as loud as you want. Its actually easier than you think. I have a Feb. 2005 sticker on my truck and it hasent been inspected since I bought it.

[anfo]

I have a 2000 v10 - 3" pipe from the Y-pipe to an FM40 with dual 2.5 out, I am currently in the market for a cheap high flow cat. The v10 with no cat is so loud it sets off some car alarms when I go by, I wish I never took it out.

[Cool1996]

www.mileliminators.com will hook to your downstream o2 sensor and your computer will never know you neutered your truck exhaust