Exhaust Pipe Size? - Between Cat and Resonator

My cat's got stolen, and the thieves sawed it off right up to the resonator, leaving no pipe to connect to. Can you tell me what size the pop is that comes out of the resonator? ID and OD? Seem like when I crawled under there and measured it had a one and a half inch ID and best I could tell a 1.75 inch OD. So I'm going to have to weld on a piece of pipe to the resonator. I have an after-market on order and trying to determine what size the pipe is on that aftermarket Pat. Do you know what yours is? Thanks.

 

Find a salvage yard with a Gen 2. Most likely they all have the cats removed, but you can typically purchase everything after the cat for about a dollar a foot, including the resonator. Just find one that had the cats removed and still has the pipe forward of the resonator. I've bought a handful like this. Makes it much easier for swapping out exhaust systems when I can have one already mocked up ready to go. I can get actual pipe dimensions and post them after I get back this afternoon.

 

1.674-1.692" as measured around the entire outside diameter. I think 1 5/8" is going to be a bit too small, but any muffler shop can probably expand it.

(~42.5 - 43 mm)

 

If it's one of those that has a threaded shaft down the center with 6 or 8 long metal pieces, don't waste your time trying to expand an exhaust pipe with it. You'll get way too frustrated. They're really only good for flattening out dents and similar stuff.

 

that’s the number I got measuring my 3rd gen at reg pipe dia just downstream of last cat or whatever it is. Maybe 43.1~.

 

If you don't live in CA or NY, I'd just buy an aftermarket whole system.

 

43 mm translates to approx 1 11/16”.

 

I found The auto parts store has a bunch of adapters for tailpipes just take your parts and get what you need


iPhone ?

 

I ordered a different donut but when arrived to pick it up the Napa store swapped it for 31379 and like you said it's about .100" to small and I had a hard time fit, and after it did seem to fit, it leaked. Not looking forward to taking everything off again. The good thing is I used U bolts before and now am going to use lap join band clamps instead since the Ubolts seemed to leak.

 

Almost $2,000 for a couple cats from a 2009?! Wow. Did they contain more of the expensive metals back then? Thats cray

 

In our area in California, the dealers were quoting 3 months to get an OEM in stock at $2500. So $2k to get your car on the road today isn't so bad.

 

My daughters each have Priuses. We just had a catalytic converter stolen. My plan is to put aftermarket cats on both Priuses. I will keep the OEM cat for when the aftermarket cats fail, or if we ever need to pass California emissions.

I have searched the internet for a reducing lap band coupler. The after market catalytic converter I bought came with a 2" pipe. It is too big to clamp down with simple U-bolt exhaust clamps. (I don't know if I could make it airtight if I cut a couple of notches in the the larger pipe to help it cinch down.)

I see reducing lap band couplers for 2.25" to 2", but nothing from 2" to 1.75".

Autozone sells a 2" non-reducing coupler (Exhaust Pipe BRExhaust 265-827). I don't know if I could put some muffler tape on the outside of the stock 1 5/8" (or 42 mm) pipe to create enough space to make an airtight seal, or not.

I'm trying to solve for simplicity here. I want to be able to drop out the aftermarket cat and replace it with the OEM cat (for the purposes of passing California smog; both my daughters live in Southern California), then put the aftermarket cat back in. I want it to be as easy as possible, not only for fewer points of possible failure, but also so my daughters' boyfriends can make the switch.

Butt joints would be the easiest, because then I don't need to get any longitudinal distraction to slip one pipe over the other. But, since the pipes aren't presently the same diameter, I am worried about joining the butt ends with off-the-shelf parts.

I could get reducing pipes (like from O'Reilly's, or Autozone). Ideally, I'd reduce both after market catalytic converters in a way that they will have the exact dimensions of the OEM catalytic converter when I cut it out. At that point, the junctions will all be 1.75" to 1.75" butt joints. (In other words, the reducing coupler will be "permanently attached" (though, not necessarily welded) to the after market cats.
Providing I can find a 1.75" butt joint that will give me a proper seal, that might be the best compromise.

Does anybody with real experience have wisdom to offer? Again, a 2" to 1 5/8" reducing lap joint band clamp is what I am after. But I can't seem to find it. Perhaps I am using the wrong search terms.

Thanks for your help.

 

Also, should I be using exhaust pipe sealer, or will that make it more difficult to undo?

 

A friend has a 2012 Prius and his cat was stolen TWICE - he lives in San Francisco. He ended up buying some kind of "cage" for it when he replaced it the 3rd time. I'm not sure if "cage" is the correct term - but it was something around that made stealing the cat very very difficult and much more time consuming; so our fellow humans WHO ARE ACTIVELY TRYING TO MAKE THIS PLANET WORSE have a harder time doing so. OR, he says, will notice that it's protected and move onto another vehicle. I still can't believe people sometimes. Probably take it to some shady scrap metal guy and get a tiny fraction what it cost to replace and spend it on booze or whatever.

 

Not sure how long the stub pipe remaining from the resonator is but you could try the exhaust pipe expander, rent borrow one from Advance or Pep Boys.


Curious which aftermarket cat did you buy? The Autosaver88 from Amazon slides right on to the front pipe of the resonator.

Another aftermarket cat on Amazon had the dimension chart.

Another poster mentioning odd pipe size matching. Post #6 and #9

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