Catalytic converter 1999 V10 275 hp

[Lake11969]

I see my 99 has a catalytic converter, my last class A chev didn't have any with duel pipes. So my question is has anybody taken there catalytic converter off to run better?

[Nick-B]

Are you SURE it is a catalytic converter you are seeing and not a resonator?
Regardless, as long as you are compliant with your state regulaltions and inspections (if you have one) removing the converter will not hurt the engine and will likely improve performance. Ford exhaust systems are fairly restrictive and the muffler probably has more restriction than the converter.

[Topflite51]

Unlike previous years of F53's, the V10 does have a convertor. Removal would hinder performance, as the 4 O2 sensors 2 before the convertor(upstream) and 2 after(downstream) would feed confusing info to the computer.

[Wanabee FTer]

In the state of CA it is illegal to modify the factory emissions system. It may or may not be illegal in your state of residence to remove emission components. 1999 was the first year Ford used OBDII emissions on the F53 chassis. 1997 was the last year Ford produced the F53 with OBDI and did not use a catalytic converter. The OBDI F53 was not produced in 1998, but rather the V-10 OBDII was built mid 1998 and introduced as a 1999 model.
I agree with Topflite51, it will definitely confuse the emission control computer and will cause drivability and gas mileage concerns, also a check engine light will stay on at the dash. In this case it pays to be environmentally conscious.

[tderonne]

Some info:

It's illegal in all 50 states to remove your cat.

OBDI and OBDII have nothing to do directly with emissions levels. Sure they are related, but tailpipe standards and tailpipe standards, and the "D" in OBD is diagnostics, different animal. Some OBDII faults are tied to relative emissions levels, unlike OBDI which just monitored basic system function.

At least '99-'04 V10 F53's have no downstream O2 sensors. Hence, there is no catalyst monitor in the OBDII system. (Not sure if the 3 valve's have downstream sensors or not.)

In reading probably 1000's of posts about "improving" the performance of both Ford and Workhorse motorhome chassis, I haven't read 1 single post with any real data about modifying the exhaust. Like the cat is has XX kPa of backpressure near peak power. Mine is bone stock, and will stay that way until I put some pressure transducers in the system and get some data.

[Wanabee FTer]

Quote:

Originally Posted by tderonne At least '99-'04 V10 F53's have no downstream O2 sensors. Hence, there is no catalyst monitor in the OBDII system. (Not sure if the 3 valve's have downstream sensors or not.)

Tim,
This statement is contradictory to what OBDII actually is. OBDI (On Board Diagnostics standardized version 1) did not require a downstream O2 sensor.
OBDII incorporates 1 or 2 downstream sensors to monitor actual performance of the catalyst system. Check this site for more OBD info

[tderonne]

I'm fully aware of what OBDII is. It's been part of my job since 1992.

'99 - '04 F53's do NOT have a downstream O2 sensor. There's a '99, '01, and '04 in my family. No downstream sensors. I don't know if Ford used an exemption (there were fines per vehicle you could pay to not do certain things), or if over 8600 pound GVWR trucks got a break on cat monitor.

[Wanabee FTer]

I have no first hand knowledge of '99 to '04 Ford Super duty design, but coming from an automotive background it does not make any sense to me.
Are all your SD's Federal or CA?

[Topflite51]

I do not know for a fact, but at a recent family get together in CA, a relative who does tend to exaggerate issues, was claiming he had just picked up his MH (99 F53) from a Ford truck center for some engine repair work. They replaced his cat and 4 O2 sensors and muffler for $2100 and change. I guess he was ripped off more than I thought. Maybe I will call him up and stir the fire up. Nah

[Lake11969]

Thank alot, great information, will leave mine on, but I have no downstream 02 sensor on my pipes.

[Wanabee FTer]

Lake,
If your looking for more power have you looked into the Banks system. I have read good things about their products for the early Ford V-10.

[Lake11969]

Don't know, just pick it up in Dallas tx. Very happy,going to fl. soon pulling 92 toy celica convertible will see then.