PCW Exhaust mods

An exhaust mod/modification can be anything from a full straight pipe system, to a simple resonator delete, so a better question may be "what is a pcw exhaust mod?" or "what is a modified factory exhaust?"...

in that case then it always involves removing the factory system from the car and opening each section of that factory system (backbox, resonator, catalytic converter etc) from above to gain access to the silencers internals, once inside you can manipulate the pipework/baffles to gain better flow which (when done properly) gains more volume and a better tone.

when the job is complete you have all the advantages of the best aftermarket exhausts, but it all looks just like the standard factory exhaust did before any work was done, tips look as before, valves function as before (as nothing was changed other than the internals), so its very warranty friendly and incredibly cost effective.

Yes, except when catalytic convertors are gutted or petrol particulate filters are gutted.

the rest of the exhaust (backbox/rear mufflers/resoantors) can all be internally put back to standard volume and tone

Theres actually quite a few solutions on bmws..

firstly i have my own physical solution which works on newer bmws.

I insert a passive device which fools the ecu into thinking the particulate filter is still there!

we can also code out the filters (only drawback being you need to avoid software updates from the dealer and it will also throw an engine light if you sell the car and the new owner gets a software update)

we can also combine the 2 above solutions giving you a future proof solution.

theres also lieb connectors which fool the ecu but these are not guaranteed, they also do a 'can bus' device which is guaranteed but it involves pinning into the stock harness and is not a cheap solution.

all other manufacturers from what i've found (mercedes, audi etc) need mapping out