I have a 2.2L automatic. I currently have a 2.5 "ZZP catless downpipe in the garage that im ready to install, now my question is I want to order the shorty bad mab headers.

Those headers say the end is 3" , so how would it bolt to my 2.5" zzp dp?

Next question, I have a tsudo N1 catback installed right now . So to me the piping measurements don't add up which is basically my predicament.
Headers 3" to 2.5" dp to 2.25 catback piping. Will it work out?

 

Yes it will work out. Its better to have the piping gradually get smaller toward the back of the exhaust because as the exhaust gasses cool, it looses velocity. The smaller volume will keep the velocity up as the gasses get colder and exit the vehicle. As long as the flange on the header is the same size as the DP then you will be good, and I think they are the same size.

 

Why not just get the ZZP header? guaranteed fit...

 

Because he already has a ZZP downpipe. The BadMab will fit. Lots of people run this setup.

I thought the tsudo was 2.5, so not sure on the catback.