PCW Exhaust mods
N55 exhaust mod
Starting at £360
The exhaust mod for this range is very much like the mod for the M140i.
I've modified lots of these with great results, a deeper, aggressive sound with clearer more defined crackles.
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the process involves me removing the exhaust from the car and opening the silencer from above, inside is a series of chambers and pipework, I use stainless parts and welding to internally improve the airflow, once put back together and back on the car no evidence of my work can be seen.
this also leaves the valve functional so you still have a loud/quiet option, meaning no drone when cruising.
the first picture is of the '35i' exhaust, the only thing differing in the models is the size of the bulge/bullet shaped resonator (its larger on the 340/440i)
Backbox only is £360, Backbox and resonator is £380 (£400 on the 340i/440i due to larger res)
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Below are some videos of the mod done, this is just the backbox modified.
Here's with resonator as well...
resonator gives it probably 7% extra volume, not something worth doing on its own but as part of the whole its worth it in my opinion as it makes the crackles a little clearer and the tone fractionally more aggressive and I'd always recommend doing both.
i have couple of extras I can do on these, secondary decat (no mapping needed) i can also map any 35i with BM3, stage 1/2 etc
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this is a stage 2, so loudest possible