Cold Start Daftness
Discussion
kapiteinlangzaam said:
Isnt it for emissions, get the CATs up to temp ASAP.
My previous Mazda CX5 2.0 used to rev its tits off on cold start, so much so the user-manual made a point of explaining it. However, you couldnt hear its exhaust so no worries
Its dumping fuel into the cylinders and changing the ignition so that most of the combustion happens outside of the cylinder to warm up the cat. Amusing to see the cat temp probe go from 10c to 600c in 30 seconds.My previous Mazda CX5 2.0 used to rev its tits off on cold start, so much so the user-manual made a point of explaining it. However, you couldnt hear its exhaust so no worries
My old E55 was subtle and quiet even on very cold start ups and I always dreamed of replicating the C63 blip...!
My current E63 with 5.5 biturbo is pretty ridiculous. I park close to my garage door and it rattles the whole house and wakes up the children every morning! Personally though I absolutely LOVE the noise - it sounds so much more aggressive in that first 15-20 seconds then quietens right down to a gentle purr...
I'd rather hear a few seconds of amazing V8 with turbos spooling up than my neighbour's E220 diesel ticking over!
My current E63 with 5.5 biturbo is pretty ridiculous. I park close to my garage door and it rattles the whole house and wakes up the children every morning! Personally though I absolutely LOVE the noise - it sounds so much more aggressive in that first 15-20 seconds then quietens right down to a gentle purr...
I'd rather hear a few seconds of amazing V8 with turbos spooling up than my neighbour's E220 diesel ticking over!
Dannbodge said:
The reason the turbo cars are much louder is due to not only the raised idle, but also the higher amount of fuel being injected and the turbo wastegates being wide open.
Why would a turbocharger wastegate need to be wide open at idle? All the turbocharged cars I've owned used boost pressure to open the wastegate, so the default position with no boost is fully closed.I've always felt anti-social starting my Z4 35i in my allocated parking space which is only a few meters from my neighbour's front door!
I went in to the dealership to buy a 28i I had seen, started it up and it sounded like any normal car. Jumped in the 35i they had "just to see if I liked it" and the cold start cycle alone gave the car a totally different feel. I ended up buying it. These days it is more embarrassing than anything, it sounds like the car is broken.
Is it all for show or a real mechanical reason behind?
I went in to the dealership to buy a 28i I had seen, started it up and it sounded like any normal car. Jumped in the 35i they had "just to see if I liked it" and the cold start cycle alone gave the car a totally different feel. I ended up buying it. These days it is more embarrassing than anything, it sounds like the car is broken.
Is it all for show or a real mechanical reason behind?
My C63 has a characteristic bark on start up. A little noisier when it's cold, but even on a warm start it barks. I love it. I don't really use the car in the early mornings, but even when I had my very noisy TVR the neighbours didn't complain.
Merc:
https://www.youtube.com/watch?v=U3Qe2v_jASE
TVR:
https://www.youtube.com/watch?v=fDaxrim7hHM
Merc:
https://www.youtube.com/watch?v=U3Qe2v_jASE
TVR:
https://www.youtube.com/watch?v=fDaxrim7hHM
Edited by sebhaque on Thursday 19th January 16:35
It's funny isn't it, how ones views on things change? I never really thought about it before. I've had some silly cars over the years. I can't help but think on a lot of the more modern stuff it's engineered in - to make it as loud as possible on cold start. It sounds like somebody playing a very loud, heavily compresed MP3 of 'fast car starting up' when this M4 kicks into life. On reflection, it's pretty sociopathic.
essIII said:
kapiteinlangzaam said:
Isnt it for emissions, get the CATs up to temp ASAP.
That was my understanding too. My previous M135i did it, and current C63 does too. It definitely seems to be a modern trend with 'performance' cars but I was sure it was to do with warming the CAT, presumably so that the car can 'cheat' its way into a lower emission banding?HappyMidget said:
Not really needed, the manufacturers have over compensated on the Coolant temp startup tables. EG, this is my 600+ BHP Supercharged 6.2L V8 VXR8 GTS starting up from cold with the Bimodal exhaust fully open. Really not much difference to a warm start. Idles straight to 600rpm. https://youtu.be/aVdaKHiDw1s
Not based in / around Woodley by any chance are you?I'd second that DB11 example given earlier- at least give the option of a quiet start. Not everyone wants to sound like a t
t at 6am in a residential area. Totally different at the ring or goodwood or whatever. I'd guess on the full sports models, the RS's, M's and so on that it's all, or 80% theatrical. And sometimes we don't want theatre, we want radio 4.
t at 6am in a residential area. Totally different at the ring or goodwood or whatever. I'd guess on the full sports models, the RS's, M's and so on that it's all, or 80% theatrical. And sometimes we don't want theatre, we want radio 4.My XFR with aftermarket exhaust is defiantly antisocial on my 3am starts.
Just to clarify, I'm OK to select drive almost immediately and move off sedately with no adverse effects except potentially the CATS? I've had compliments and vaguely mumbled complaints and would prefer not to annoy anyone.
Just to clarify, I'm OK to select drive almost immediately and move off sedately with no adverse effects except potentially the CATS? I've had compliments and vaguely mumbled complaints and would prefer not to annoy anyone.
Joe5y said:
HappyMidget said:
Not really needed, the manufacturers have over compensated on the Coolant temp startup tables. EG, this is my 600+ BHP Supercharged 6.2L V8 VXR8 GTS starting up from cold with the Bimodal exhaust fully open. Really not much difference to a warm start. Idles straight to 600rpm. https://youtu.be/aVdaKHiDw1s
Not based in / around Woodley by any chance are you?
HappyMidget said:
Joe5y said:
HappyMidget said:
Not really needed, the manufacturers have over compensated on the Coolant temp startup tables. EG, this is my 600+ BHP Supercharged 6.2L V8 VXR8 GTS starting up from cold with the Bimodal exhaust fully open. Really not much difference to a warm start. Idles straight to 600rpm. https://youtu.be/aVdaKHiDw1s
Not based in / around Woodley by any chance are you?My Honda starts itself on the electric motor. It hums into life, rather than clicking and firing like a conventional starter does.
My Triumph Daytona with a carbon race can is embarrassingly loud on start up. I rarely take it out early, but when I do I have to start it, then kick the stand up and ride slowly down a gravelled back lane as it growls away in first gear and high idle. It's a lot more tuneful when it's warm and being put away. The noise as it fires and settles into running is just lovely and feels so satisfying.
My Triumph Daytona with a carbon race can is embarrassingly loud on start up. I rarely take it out early, but when I do I have to start it, then kick the stand up and ride slowly down a gravelled back lane as it growls away in first gear and high idle. It's a lot more tuneful when it's warm and being put away. The noise as it fires and settles into running is just lovely and feels so satisfying.
HappyMidget said:
Joe5y said:
I actually think we live fairly close - I'm in Munro Ave.
Lol, 5 minutes away, am on Tennyson Rd 
Errrm, sorry, my clutch may have just slipped
Edited by HappyMidget on Thursday 19th January 20:04
PS e60 FR55JOE
i love the loud crack of my C63 starting up from cold in the mornings.. its so weirdly exciting to hear it. i knew it was loud, but its not until someone else in the house starts it up to move it or take it out... from inside the house i always chuckle to myself how loud it is lol.
my boss's F10 M5 sounds overly loud on a cold start too.
my boss's F10 M5 sounds overly loud on a cold start too.
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