basically as the title states. I am living in a non emissions testing state for the first time in my driving life and am wondering what a CAT delete will potentially do for me. I know it should help my fuel efficiency and power. How true is this? Also, will I get a lot more exhaust noise? I am not interested in any sort of loud exhaust. Anyone here done this yet?
CAT delete=better mileage/power?
- Thread starter McFly2003
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veloindy
New member
Uh, CO has emissions testing...
http://aircarecolorado.com/
Unless you moved and your profile is wrong...
Certain areas, yes. Up in the Denver/Boulder area, where the population is much more dense. Everywhere else, only diesels are subject to emissions testing. At least this is what the lady told me when I registered my truck. I have only lived here as a full time resident since August so I am still learning
mikebontoft
New member
it will make it louder... won't do much for you besides a check engine light until you figure out how to fix it
veloindy
New member
I would double check that before you do anything drastic. I work with a guy who commutes from El Paso county, he said it was required.
Consider resale too.
philsey
New member
Curious how you KNOW this? Seems to me some pretty smart Engineers designed this engine's ECU to monitor and control lots of pretty sophisticated stuff.
I'd wish you good luck, but I wouldn't mean it. Seems like an excellent way to FU a perfectly good piece of machinery.
Hang in there for the S/C...
Alright, so maybe I know this from first hand experience :jump:, just based on some unguided internet research. An uncle of mine did a delete on his '98 taco and said he was seeing a noticeable increase in efficiency.
Like I said, I don't have much of anything to go on, it is more of a curiosity thing. If it were truly worth doing, I'd consider looking into it, but it's looking like its not
mikebontoft
New member
It would not be worth it. same with high flow cats... factory cats since the mid 90's have been "high flow." People report gains from these likely for two reasons: carbon buildup in the old catalyst material and increased diameter over stock.
there's no reason to have to deal with the smell either... Granted the 5th gens are no doubt very efficient, It's just not worth it.
there's no reason to have to deal with the smell either... Granted the 5th gens are no doubt very efficient, It's just not worth it.
Agree.
harper7
Senior Member
5th Gen 4Runners actually have 4 smaller cats with 2 being part of the exhaust manifolds coming off the engine and 2 just aft of the manifolds.
When I had the bolt-on Doug Thorley headers on, they delete the 2 front cats and it's definitely louder with just minimal gains in HP really. On my unofficial scangauge HP readings I picked up around 10-15hp at WOT. URD and others make SIM's to fool the O2 sensors so you don't throw codes or lights.
I had the headers on for the first two years and took them off as I couldn't pass emissions even with sims. Kept failing for a low voltage o2 sensor.I'll probably put them back on once I get a supercharger to see how much of a difference they make then as they are a real PITA to change out every year just to pass emissions here in Texas.
As far as being high flow cats, they have alot of pretty small honeycomb holes and look pretty restrictive to me .... Here is a pic looking inside of one of my cats I took when I had them off.It's normally light gray but I shaded it blue and use the pic for my background on blue themed phone .lol
When I had the bolt-on Doug Thorley headers on, they delete the 2 front cats and it's definitely louder with just minimal gains in HP really. On my unofficial scangauge HP readings I picked up around 10-15hp at WOT. URD and others make SIM's to fool the O2 sensors so you don't throw codes or lights.
I had the headers on for the first two years and took them off as I couldn't pass emissions even with sims. Kept failing for a low voltage o2 sensor.I'll probably put them back on once I get a supercharger to see how much of a difference they make then as they are a real PITA to change out every year just to pass emissions here in Texas.
As far as being high flow cats, they have alot of pretty small honeycomb holes and look pretty restrictive to me .... Here is a pic looking inside of one of my cats I took when I had them off.It's normally light gray but I shaded it blue and use the pic for my background on blue themed phone .lol
92-SR5
New member
I run a cat delete (test pipe), it makes your exhaust a lot louder at certain rpms. I'm running a flowmaster with a 4 banger though. I did notice a slight gain when I am going up hills. No difference in MPG though.
It does make your exhaust smell a bit but I'm used to it from being around older vehicles my whole life.
I'd just leave them on your vehicle though. My 4R is much older technology therefore I don't have any o2 sensors or anything behind my cat.
It does make your exhaust smell a bit but I'm used to it from being around older vehicles my whole life.
I'd just leave them on your vehicle though. My 4R is much older technology therefore I don't have any o2 sensors or anything behind my cat.
