I see a lot of you run catylitic converters. Any reason?? We don't have to in Ohio, it's not law.

 

I would like the planet to last as long as my 4Runner

 

CA emissions. Its the law unfortunately.

 

Actually, you do have to, it's federal law. Just because your state doesn't inspect for them doesn't make it legal.

 

Do a search on the subject. There have been a number of members who didn't understand the federall law either.

In short, keep the cat.

 

oops, already sawzalled it off. Maybe I'll buy a new one when I rebuild the motor. Don't want you all to think I'm a tree killer>

 

its stupid to not run one, lets say you dont care about killing all of us and the planet..... it makes your truck throw engine codes, and doesnt let it run right.... and beside modern cats are hi flow so there is no reason not to run one.... and basically unless it is a purebred racecar, the assumed performance gains really isnt much if any, it might even hurt the performance

 

oh yeah, it is federal alw as well, jsut because your state doesnt inspect for it, doesnt mean that you dont have to have one, all cars sold and run on us roads must have them epr DOT

 

Huge fine and jail time if you get caught without one.
Plus its bad for the environment.

 

I know when I put my long tube headers on my Dakota R/T 5.9L and removed the 2 precats and the main cat, it sure liked it. I used an o2 Simulator box to trick the PCM into thinking the cats were their. It generated the correct voltage signal to the pcm thus no codes. I ran a single 3.5" exhaust off the headers and the 5.9L could finally breath. Got me 4 tenths in the 1/4 mile and 4 mph.

I noticed that some people wonder why the Supercharged V-8 Toyotas don't make the power that everyone thinks they should . It's mostly due to all the restrictions in the exhaust... i.e. CATS. High flow or not.... the more restrictions you add, the less power you will make, especially when your trying to force more air in. Putting 3 or 4 cats and a MUFFLER on a V-8 exhaust system is like trying to breath through a straw the rest of your life... you would make a lot of power either...

 

I didn't run a cat for years, I thought it was a big power robber, then I got busted on my state inspection, I put a freeflow cat on at $90, no difference and now I'm legal!

 

It's not worth the power gain (most of which is imaginary anyway), never mind the hassle if you get busted for not having one.

 

the only plus from sawing my catty off is that the old beast takes off a little quicker, but other than that, no difference, good or bad. But, to make all of you happy, I'll put one on. Any suggestions on a nice, quiet exhaust that will let my 3.0L breathe??

 

also, do they make headers for the 3.0L??

 

Yes but you need a body lift to fit them (i think)

 

I have a 3" body lift I'm waiting to put on as soon as I'm ready with the new bed.

 

Yeah definitly keep the Cat if you have inspections. However I live in Alabama and we can drive Pro stock cars on the street and no one cares. My Toyota is totally stock and has it's Cat and I agree that their is little difference to be had on a stock V-6 or 4 cyl. I had a 92 Nissan V-6 that I removed the cat on and I never noticed anyting.

Proper Backpressure for your application is the key in any exhaust setup. Big blocks, high h.p. Small blocks, and supercharged/Turbo setups all need to breath.

Gotta think how much power old school engines made though ... LS7, 426 Hemi, 427, etc. They made it with a Carb, pushrods, and 2 valves per cylinder. Very low tech now days

Emissions have really killed the true power any engine can make. Auto Makers have and will continue to have to dig deep to find ways to make power as emissions get tougher and tougher.

When Cats first started being, vehicles only had one.... now some have 3-4 plus a Resonator and muffler.