I have a question for others.

Does a M or QS exhaust increase power (bhp or torque) or affect fuel economy at all?

 

i am expecting pretty decent HP gains. the factory exhaust is highly restrictive and you can feel it when you floor it. Powerful UK has a video of them installing a v8 system on their p300. they cut the muffler open and you can see very small highly restricted pipes which lead to closed pipes with small vent holes. it’s pretty odd how it’s all manufactured

the Milltek has very little baffling even with the valves closed

forced induction engines gain power with more air flow in and out

as for better MPG it’s debatable. with more power you will get to speed limits with less gas so maybe if you stop flooring once you get to speed. maybe

i will most likely be heavy on the pedal to hear the exhaust

 

Yes I just saw the M site actually claims 8-10% power gain.

I’m very excited about the M exhaust. I guess my only concern is whether the non-resonator version I was recommended will actually be quiet enough in comfort mode on motorways. I really don’t want a droning noise for hours on end

 

this was my worry and i ended buying both straight pipes and the center resonator. they bolt into place and you can switch them out.

US cars don’t have opf/ppf which restricts noise by a lot. read a lot about it and it’s a huge filter before the cat.

having experience with M p400 exhaust and non resonator it was too loud and i added an aftermarket resonator

the extra straight pipes was only 150 usd. buying the resonator only will be pricey

 

I love the quicksilver. Once it's on its on. No reason to even have it plugged in unless one wants to change the note. Carbon tips, easy install. And ENGLISH. it's dope on my lr d90 v8