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I had KPM 2.5 inch full exhaust, intake and tune done. AFM was disabled as well as a few other tickles done in the tune. Went from 213 to 275 ATW (Dyno Dynamics). Goes like a 6l v8 should. Sounds so nice at all revs and unbelievable above 4000, it roars at a note just higher than most commodores I hear at WOT. Quite a unique sound. Maybe all brands of 2.5's sound like this??? I've got such little drone (in my wagon) that I don't even really consider it drone. I often wonder why I didn't go 3 inch. I think it would have to be 50% more droney to worry anyone.
I'm calling the AFM disabled KPM 2.5 inch full exhaust drone free in a VF wagon!
For anyone thinking KPM, (and quite possibly any brand of exhaust) I can say that the 2.5 inch when cruising will only turn car enthusiasts heads, (whose ears tend to be incredibly receptive to approaching performance exhausts) , unless you're accelerating aggressively above 3000 or engine braking down to 3000 in which case probably anyone within 100m would be looking. For those wanting notice at low rev cruising from every girl and her dog, don't even consider the 2.5 inch, it just isn't loud enough. I seriously think for those wagon drivers amongst us that the 3 inch drone wouldn't worry even the fussiest soccer mum, however I am only guessing that.
Any VF wagon owners out there with a full 3 inch KPM that can comment?
Personally I would no longer recommend KPM for performance work on my ride. I used them for a cam, tune etc. on another brand of car and paid an arm and a leg and only received an ankle in return. Plus a damaged power steering pipe I had to also pay for. I went to another tuner and had the tune sorted correctly. That said I don't know what they are like with GM products but they have done their dash with me.
VF Redline here with a bit of work done;
1 7/8 ceramic Headers
3 Inch KPM exhaust
OTR Intake
224/228 cam
25% underpully
Personally I would never buy a Walkinshaw system, they're a great marketing company but their exhaust isn't even their own. KPM however manufacture their own system.
I find the Walkinshaw exhaust has a very dirty, dull sound to it where the KPM system sounds clean.
W310
KPM 3 Inch - on a VE but it's the same engine and same system
My system warm start up idle
[video]https://video-lax1-1.xx.fbcdn.net/hvideo-xpf1/v/t42.1790-2/10671165_789337344459468_1887805833_n.mp4?oh=f2fba 1ae4db38be6ce7e241fec2b5b4b&oe=557FA710[/video]
Your saying KPM exhaust is nicer blah blah blah, yet you have a walkinshaw badge on your SS? WTF, doesn't really make sense pal. The walkinshaw systems ive heard sound all as nice as the one in your video, furthermore you modified the rear original mufflers on your KPM system, so its not a true indication of the note. Actually it really is quite cackly with your cam and not really as clean a sound as the 310 walkinshaw and you have said 2.5'' is loud enough, walkinshaw system is 3'' to 2.5'' no drone, no modifiying rear mufflers, no need to put a kpm badge on with a walkinshaw system
KPM Don't manufacture there own systems infact Exhaust Technology does for them. Marketing is a common strategy used by businesses, to sell a product
exhaust is personel preference, im glad you have been able to justify spending bucket loads , if a xforce system had a KPM badge on it, you wouldn't even know the difference.