What are the pipe sizes going into and coming out of the Catalytic converter?

I am not finding any specific specs on the pipe diameter but looking at this diagram below it appears to be a 1.5-inch diameter pipe.

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms

Basically, if you take a look at the diagram below you will see the clamps are M112 clamps.

These are for a 1.5-inch diameter pipe so that would make sense for this vehicle.

Please see the info below and let us know what questions you have. Also, if this turns out to be wrong, please let us know.

Thanks

To be perfectly clear, that would be outer diameter, correct?

Correct. Here is a link to Summit that will help with the exact measurements for these clamps:

https://www.summitracing.com/parts/aph-m112?seid=srese2&utm_source=bing&utm_medium=cpc&utm_campaign=Brands+|+A&utm_term=4581733679766074&utm_content=GSAPI+5e2b1603362ef

Thanks

Okay. Where I made the cuts, I found the inner diameter before the converter to be 1.75in and the outer diameter after the converter to be 1.75in.

I may never understand why they can't just keep consistent pipe sizes throughout the system. It makes for buying multiple adapters, connectors, and clamps. And it makes extra trips to the store.

Haha. I totally understand. Changing the pipe size increases the airflow speed.

In other words, some engineers felt they could get a tenth of a percent better fuel mileage or power by doing this. Very little thought is given to serviceability.

Unfortunately, this is a common issue that the service world has dealt with for a long time.

They don't do it on purpose but unfortunately that doesn't help. Thanks for the updates.

Ah, I think that Paschal's Law or something. It's been a while since physics class, but it makes some sense. To me though, while increasing speed, it would still seem to be restrictive of total volume flow. I mean if you put a funnel at the end of a tailpipe, what comes through the funnel would probably blow better than an air compressor. But the engine would eventually get backed up and die out, as if the catalytic converter were clogged. At least that's what's going through my simpleton head.