dual exhaust and catalytic converters

How many catalytic converters does a tundra have? I have 2 pipes before my muffler and on coming out .why?

 

2 cats, 2 post cats... 2 front ones are usually the ones that matter, second assuming are for redundancy to further lower emissions..

 

So if replace exhaust after catalytic converters I can have dual exhaust? Why is it this way now ? How would that effect emissions if make it dual?

 

It wont impact anything... just how they will place the sniffer hangers if you smog. meaning 2 instead of 1.. it's been this way for a while.. my 93 Lexus sc400 has 3, 2 main and 1 way in the back before it splits into 2.. most just hack that off and build the dials with no issues.. but its mainly due to the EPA and Cali.

 

Passing emissions is good I'm just wondering if go dual exhaust what's the benefits from that ? Gas mileage is different from Dakota I had . I've been seeing TRD dual exhaust and wondering about it.

 

Search around here, theres is a wealth of knowledge from all the members here... I'm more lame in Kali and have remained single exhaust... so that's pretty much the end of my input, lol.

 

They don’t even use the sniffer here anymore if you’ve got an OBD. Just a visual and hook the computer up to the OBD. As long as you haven’t unpluged the battery and reset the computer in the last hundred miles or so, and no engine lights, GTG.

OP You can do anything you want to the exhaust cat back. One of the beautiful things about the way Toyota designed the exhaust system. You could have true duels without major modifications. Although the single outlet tail pipe is sufficient.

I went with this. Two mufflers into a wye pipe. Unless you’ve got power adders and long tube headers, there is no significant gain into making it a true duel.

 

My 02 Celica got the sniffer... last year... I moved it since so that was the last time for me.

 

Interesting, are those and OBD I? I think that’s what my Sequoia is I don’t recall if they used the sniffer last time. My wife’s 08 XB just got the computer hook up. Haven’t done my truck yet.

 

Never done the Tundra... my Celica is an OBD2 I got the computer scan, visual inspection, sniffer followed by the tech revving it to about 3 to 4k rpm... before checking his computer and finishing up the test... not sure if it's a Nor Kal thing, never encountered this in So Kal... transferred all my stuff with my Tundra, so this was my last test for me...

 

Will it make a difference in gas. My mug is less in tundra than Dakota and it's same size engine. Would it make a difference in that? Why is it going from 2 to 1 now? If went to 2 what's difference?

 

Kieth @dirtydeeds is who you seek