I'm looking into buying a random tech downpipe to keep both cats. I was told that having both cats will just shorten the lifetime of the cats. How long do cats normally last?

I'm basically hoping to just to do cobb stage 2 with a gutted uppipe, downpipe, and stock axleback. How likely is it that the cats will burn out?

thanks

 

If the car is operating well they should last the lifetime of the car.

Notice i said "IF"...as a missfire or a rich condition in the a/f ratios for a extended period or leaded gas kills cats quickly.

I would check and see if the Random tech downpipe is smog legal here in CA...before you spend $$$ on it

 

IIRC, state law requires cats to last 100k miles and replaced under warranty if failed prioro to that. That's why on the RX-8 they need extremely strong cats which kill a lot of power since rotarys run very very hot, the cat needs to withstand the heat for 100k miles.

 

Thanks for the reply. I'm of the understanding that pretty much nothing is legal anyway. I think I've read enough to know that with two random tech cats, I will definitely pass the sniffer test and I would expect to pass a visual, although that's always a risk.

But I like the environment, so I'll do what I can and still have fun

 

California law says that Mass Airflow Meters and the factory catalytic converters must last 7yrs/70k miles, otherwise the dealership must replace them under warranty.

In all other states it is 8yrs/80k miles.