My original metal line is pretty fugged up and wanted to know if I could run a few inches or so to join it to the cat inlet. Would make swapping in an ORP alot easier as well.

Will

 

A section of hose may survive, depending upon its proximity to the exhaust system. What area/section would you replace? If it is right at the cat inlet or along the side of the cat, I wouldn't recommend it. You might want to investigate your options with metallic tubing and compression connectors, or consider a 3-way cat with no air injection inlet.

 

there's special hose made for air injection, should be able to get it at any good parts store, but even it doesn't survive if you can't get it a few inches off the cat

 

I'v had rubber line on mine for about 9 months now with no problems.

 

All the way to the aspirator tube on the cat? Must be some darned good hose.

 

Depends, I've done that and melted it.

What I did on my car is used a compression fitting. I didnt have any space to make up like you do though.

 

Compression fitting here too.

The tubing used in air tube repair kits is copper--with silicone hose and clamps to piece it all together. But compression fittings make a much cleaner-looking job.

You can get 1/2" OD copper tubing and a couple of compression fittings from any home improvement store.