gutting cats cause drivability issues?

[SuperHO]

pretty sure i'm suffering from at least one clogged cat on my 98. my cheap, easy shadetree solution? gonna pop the y-pipe and 3rd cat off and gut em. now if memory serves, there's 4 O2 sensors on the gen III...two of which being after cat...so will hollowing them out cause any issues?

 

[bacernate]

ses light will come on. low end power will be compromised. also you'll have to cut the pipes or the cats themselves to gut em. x-cal might be for sale soon off my 97 if the programs are the same.

 

[SuperHO]

an X-cal won't solved my clogged cat problem. the SES bulb hasn't worked since i got the car. i'm just worried about a further reduction in fuel economy caused by improper O2 readings. will MIL eliminators from the mustang crowd work on the SHO?

 

[ThatShoGuy]

an X-cal won't solved my clogged cat problem. the SES bulb hasn't worked since i got the car. i'm just worried about a further reduction in fuel economy caused by improper O2 readings. will MIL eliminators from the mustang crowd work on the SHO?

i think he was tryin to tell you the xcal will allow you to fix the issues.. not sure....

 

[warmonger]

mil eliminators will fix the cel/ecu issues. personally i noticed no seat of the pants diff in the low end having no cats. felt more of a tq loss with open secondaries to be honest

 

[HotRodKid]

i'm just worried about a further reduction in fuel economy caused by improper O2 readings.

Primary o2's control the AFR, and the readings at the primary o2 wont change, the only thing that might change your mpg's is the change in backpressure

 

[SuperHO]

lower backpressure = higher fuel economy, yes? in the end, that's my goal...well, that and get rid of the rotten egg smell under WOT acceleration.

 

[stephen newberg]

lower backpressure = higher fuel economy

And greater chance of burned exhaust valves.

pax, smn

 

[Ian Macoomb]

lower backpressure = higher fuel economy, yes? in the end, that's my goal...well, that and get rid of the rotten egg smell under WOT acceleration.

I had that problem when I first got the car. It seemed to go away on it's own.

 

[warmonger]

And greater chance of burned exhaust valves.

pax, smn

never heard of that? if your running no exhaust manifolds,sure i could see it happening.

 

[bacernate]

A sulfer smell under hard load is absolutely normal!!! Three way catalytic converters are not like the ones made in the eighties. If that's the reason you're gonna gut your cats don't do it man. If the cats are bad you should throw a code for catalyst inefficiency.

 

[SuperHO]

i've got codes...but the check engine light's been burned out since i bought the car. three things lead me to a clogged cat...first is the rancid fart smell under hard acceleration. second is it seems down on power, and not as loud as a straight piped V8 should be. third, fuel economy sucks...like high teens, mixed city and highway. and finally, we've really started smelling gas when parking it in the garage. thoughts?

 

[SHOZ123]

Usually the sulfur smell is from the gas you are using. Try a different brand.

If you can smell gas then something is leaking.

I have a couple Y pipes if you want to come on down.

 

[SuperHO]

i may do that, paul. it's not leaking anywhere that i can see, and it always gets Shell V-power unless we're travelling and can't find it. think maybe the EVAP system might be having problems?

 

[SHOZ123]

Have you tried reading the codes?