[ilovexdrive]

i really want to go full bolton and run mhd’s stage 2+ tune but can’t go catless since i’m in new york. i have a 2009 e92 335xi and was wondering where i can buy good free flow catted downpipes that fit the xdrive model.

[CarAbuser]

You don't need cats to pass inspection. You just need the monitors to be ready.

Cheaper to get a set of empty pipes and a tune that sets the monitors than to buy 200 cell cats.

[ilovexdrive]

Originally Posted by CarAbuser

You don't need cats to pass inspection. You just need the monitors to be ready.

Cheaper to get a set of empty pipes and a tune that sets the monitors than to buy 200 cell cats.

wait could u explain this more in depth? i dont really understand what you mean lol

[CarAbuser]

Originally Posted by ilovexdrive

wait could u explain this more in depth? i dont really understand what you mean lol

If your inspection just checks the OBD monitors then you don't need to have the primary cats at all. You only need to keep them in place if you are in a country where they check actual CO emissions and not just a monitor.

You can tune the N54 such that it will report all monitors passed, even without having primary cats in place.

[roadkillrob]

All the high flow cats either still get efficiency codes or do after a year and is totally not worth the money, just go catless and get a DPFix.

[ilovexdrive]

Originally Posted by roadkillrob

All the high flow cats either still get efficiency codes or do after a year and is totally not worth the money, just go catless and get a DPFix.

what’s a DPFix?

[oVeRdOsE.]

Originally Posted by ilovexdrive

what’s a DPFix?

the module that act like a piggyback for O2 and modify the O2 value to the DME and wont throw a code.
Check google, there's few on sale, and here in the ads section.

get a freeflow downpipe,
keep the secondary cat for smell
DPfix


mine are coded out by the tune, I didnt need a DPfix, check with MHD.

[E92xiSS]

Originally Posted by ilovexdrive

i really want to go full bolton and run mhd’s stage 2+ tune but can’t go catless since i’m in new york. i have a 2009 e92 335xi and was wondering where i can buy good free flow catted downpipes that fit the xdrive model.

I am in NYC and have no problem with the state inspection without primary cats. New York inspection allows 1 monitor not to be ready. just make sure everything else is ready. no need for dpfix.

[lookalikehuuh]

I would also like to point out that high flow catted DPs will NOT prevent codes for Catalyst below efficiency codes (P0420 & P0430) without a tune or DP Fix like others have mentioned.

I have the VRSF Catted DPs and I still have to swap in the OE primary cats when I go to do smog every couple of years.

The reason I run catted DPs is because they greatly reduce the sulfur smell from the exhaust which I can't stand.