I'm in the middle of redoing my exhaust. The guys who had the car before me ran their own little cat system using magna flow hi flows. The air pump line ran to the first cat. Well I'm deleting my cats but what should I do with the open air hose? Should I plug it? Should I leave it open? Should I run it to the intake for maximum BOOST? (Justkidding.) P.S. I don't care about emissions. Frick the government.

Thanks

 

What generation/mods?

 

1986 fc GXL. No mods to engine

 

you can delete the air pump and run a double pulley on the engine to compensate for no air pump.
If you are referring to the split air pipe and want to delete the cats,then you have to find some way to operate your 5/6 ports.(aux ports) as an S4 uses the exhaust pressure to activate the actuators.
If you run an after market header then you can get one that supplies the air to the actuators,but if it does not then you have to tap the new one or make a system so that it will provide pressure to the actuators.