djfishstix

has anyone else heard a loud noise possibly the super charger once you get above 150mph? I got past this 3 times and it happened everytime I hit 150 and lasted until i slowed down.

jangy

you need to describe the sound. I haven't heard anything different at those speeds. Does it just go away when you slow down?

Jakpro1

If it's a whurrring kinda sound, I think it's just an aerodynamics noise. Think it's coming from the side view mirrors if I am not mistaken.

tbenz

possibly the speed limiter coming in

I Like Soup

I personally have only been over 150mph in my 55 a couple of times and didn't hear anything but the sound of my heartbeat!

Hammer Down

It's your conscience kicking in telling you to slow down does it sound like that

djfishstix

It came in at 150 each time and stopped when i hit 149. first time i heard it ... got to 151 then i slowed down because i didn't know what it was. the second time i hit 153 then i had to slow down or rear end someone. the third time i was going thru a minor hilly area and got the car up to 158. the sound seemed to be very present between 150-155. I know the car is governed to stop at 155 and the power did seem to cut out but I was able to get it up to 158. also, i was very cold out all 3 times .... probably in the high teens/low 20's. The third time that i did it i was able to keep the car up at that speed for about a minute before i let the gears slow it down. It was very hard to hear where the sound is coming from but i thought it was coming from either the engine or supercharger. Any thoughts?

djfishstix

Nah, my concience was saying "if only it wasn't governed!!!"

Jakpro1

Is this it???

Happens to this guy at the 290KMH.

djfishstix

thats the noise. what is it?

MB_Forever

It could be a specific road noise? Did you try it on a different road?

YSP KING

Weird...I don't ever recall that sound....

way2evil

that sounds like whistling from the wind

cte430

Take it to the dealer - just to see the priceless look on their face when you tell them you hear something at 150 LOL.

I remember I had my car in for service for a couple of minor things and told them "by the way, I hit 170 the other day and heard something". On the receipt under my description of the problem it said: "Could not reproduce problem"

m_berman

That's not definitely coming from the car. It's some sort of wind noise.

I was at 150 mph a few times and its no differnet than driving at 80 mph.

Just be sure to adjust your tire air pressure for over 100mph.

por997s

strange, I have had the same problem and posted this thread. well seen i am not the only one.

https://mbworld.org/forums/w211-amg/203535-strange-noises-high-speeds.html

Bullett

It sounds like the same noise that Chuck Yeager reported the first time he broke the sound barrier.... Maybe its the vertical stabilizer??

Jakpro1

Trust me, it's nothing to worry bout.

Just some aerodynamic voodoo going on.

Just at a higher speed. Just like the famous whistling antennas on old style cars and trucks. Dodge solved it by making the antenna ribbed before they all went into the windshield.

It's no big deal. I use my noise as my speedo. When you hear it, you know you are hammering.

KrisKeeney

It might be the edges of your lips, flapping against your ears, from the G force.

Seriously, I've only dared get to that level once (to buck fifty one), and heard nothing of the sort; but at that speed, road noise, air noise, etc., was huge

F_Porsche

Ask a German mechanic and he will be able to help you! Or atleast reproduce the problem and than fix it.
Although I doubt anybody would come in for a weird noise at those speeds. Anybody knows its just wind noise.

Cylinder Head

iTrader: (1)

Has your car ever been in an impact? It could be that your doors don't quite seal so well, or maybe your windows are a bit off. Front end impacts tend to warp the entire structure of the car ever so slightly. 1mm difference means wind gets in.

I really do not recommend going that fast in the cold. Cold tires=low grip=wow that median is coming up really fast.

SamE55

Mine does it too... sometimes even at lower speeds like 145mph or less. Does your car have the pano roof?

Hammer Down

My car makes those noises when I approach those speeds in a 1/4 run at the track

djfishstix

What should the tires be set at for speeds over 100mph

KrisKeeney

check the placard inside the gas fill up door: I recall there being a good 4 additional psi for 100mph or above; mine are always 40'ish in front and 44 in rear, but I suspect this is a bit high compared to most folks here.

But the recommendation by Merc is 4 more psi for over-100mph travel.