Question about emissions equipment

[dice2012]

Hey guys. I'm installing a swap exhaust with a cat on it. I'm wondering how harmful deleting the SAP and secondary O2 systems would be for the cat long term. I am tempted to buy the SAP pump off an e36 partout near me, or rockauto, as I have most of the other parts for the system. I'd also have to figure out wiring up new secondary O2 plugs, as the guy I got the engine from just cut the wires instead of unplugging when pulling the engine.

If it's nbd for the health of the cats, I'll just do what everyone else does and flash them out of the ECU. My main concern is the cats clogging and having to pay for a new, or replacing the mid pipe.

[Panici]

I guess it depends on who does the ECU flash.

You would want them to take out the extra fuel on startup, which along with the SAP is used to light off the cat quicker.

But if they delete the SAP code and don't change the fueling, that is less then ideal.

[dice2012]

Literally know nothing about engine tuning. Thanks for the advice.

Talking to someone in RI who was recommended to me by a NE30 member, looks like he'd probably know his stuff. I'll ask though.

[TobyB]

+1- the SAP fuelling isn't good for the engine, so if they take that out, then you can delete the SAP as well.

The whole mess was added because the EPA wanted the cats warmer quicker. But it's hard on the engine
to run it that rich when it's cold, and it doesn't harm the cats at all to warm them slower. The amount
of extra emissions isn't much, either...

t