How much pipe needs to be left to install the catalytic converter half kit?

I'll post a photo of one installed this evening, after I get home.

 

Here we go....I think one inch would be adequate if the joint will be welded. It would probably need to be installed, marked or tac welded and removed for full weld. I don't think 1" will be enough if using the clamp.

The other issue I've encountered is that the flange doesn't seal properly against the exhaust manifold donut resulting in a very audible exhaust leak. Sometimes the pipe bend needs to be tweeked to get the flange at the right angle. Also, only one version I've purchased actually had the correct bolts/springs/donut gasket. Most have Mopar crap included.

If you want true "ease" of installation, the one piece would be the ticket, assuming the extra $$ also ensures a better flange angle..

 

Can you tell me what manufacturer's product is shown in TMR-JWAP's photos? My '06 that just keeps on going had it's Cat liberated last week while it sat in our driveway.

 

You really need to take it to a muffler shop and get that connection from the car to the resonator welded its pretty rare that a bolt on will not leak. $80. Just do it right.

The other issue is they cut the wires to the 02 sensor and took the o2 sensor with the cat when they steal it so you will need a new o2 sensor.

Here's the cat I bought I and used I sold my OEM cat on ebay for $1350.

This Amazon one fits perfect and runs great. The included donut gasket with this one is too small for the 07 prius but my original donut was in good shape so was able to reuse it.
if yours is gone use the OEM gasket its $86 at the dealer. You must use the correct gasket or it will leak bad.

I painted this one bright orange with header paint so if they try to steal it again and they will try again they should be able to see quickly from the paint and the new weld its an after market cat and move along.