Anyway to make my DB9 startup a lot quieter?
Discussion
Now before the flaming starts, let me begin by saying I love the sound and volume of my DB9, especially without old fuse 22 getting in the way. However.... when I go into my office in London I tend to leave my place at like 5am. I live in a quiet neighbourhood more populated with folks over 90 than anyone else, however I also have two small children whose bedrooms are at the front of the house. The current startup routine contains a bit of a rev blip which sounds lovely, but a tad too noisy for those wee hours. My wife insists that the new car is linked to the recent early risings of the small monsters. This may be more of a question for BamfordMike, but I wondered if some form of switchable alternate startup routine could be engineered in? Less cylinders or... I really don't know I'm not a mechanic. 
If not, no worries, I'll just have to dose the kids with a quart of sudofed the night before to get around the issue.
If not, no worries, I'll just have to dose the kids with a quart of sudofed the night before to get around the issue.
I think the car starts with the exhaust bypass valves open. It may be possible for BR(or someone) to fit you a switch that will have them closed at start up. I know the valves work off vacuum and in my car the engine creates the vacuum so that would not be an option, however I'm sure I have read that the DB9 has a vacuum pump that works the valves so a switch may be an option.
F1 NDW said:
I think the car starts with the exhaust bypass valves open. It may be possible for BR(or someone) to fit you a switch that will have them closed at start up. I know the valves work off vacuum and in my car the engine creates the vacuum so that would not be an option, however I'm sure I have read that the DB9 has a vacuum pump that works the valves so a switch may be an option.
problem is the vacuum isn't held when it is switched off so the valves "relax" to open as the vacuum dies awayI guess it could be possible to plug a 12V supply in to fuse 22 for a minute or so before you start it to build the vacuum back up?
Yes it is possible to do but you will need a 3 position switch (on-off-on).
Basically the valves are operated by a feed from the body control module that controls the valve making them open on cold startup.
To make it work silent you would need to take a switched feed from the ignition, that way when you turn the key to position 1 or insert the ECU key it would activate the valves making the exhaust quiet through the entire rev range.
With a 3 position switch you get three options:
Position 1 = Ecu controlled (standard)
Position 2 = Open (fuse 22)
Position 3 = quiet (Closed)
Here is a video on how it works.
http://youtu.be/3NY1sIYMkZc
Tbh I'm suprised more people haven't had this option fitted.
Basically the valves are operated by a feed from the body control module that controls the valve making them open on cold startup.
To make it work silent you would need to take a switched feed from the ignition, that way when you turn the key to position 1 or insert the ECU key it would activate the valves making the exhaust quiet through the entire rev range.
With a 3 position switch you get three options:
Position 1 = Ecu controlled (standard)
Position 2 = Open (fuse 22)
Position 3 = quiet (Closed)
Here is a video on how it works.
http://youtu.be/3NY1sIYMkZc
Tbh I'm suprised more people haven't had this option fitted.
Black9 said:
Yes it is possible to do but you will need a 3 position switch (on-off-on).
Basically the valves are operated by a feed from the body control module that controls the valve making them open on cold startup.
To make it work silent you would need to take a switched feed from the ignition, that way when you turn the key to position 1 or insert the ECU key it would activate the valves making the exhaust quiet through the entire rev range.
With a 3 position switch you get three options:
Position 1 = Ecu controlled (standard)
Position 2 = Open (fuse 22)
Position 3 = quiet (Closed)
Here is a video on how it works.
http://youtu.be/3NY1sIYMkZc
Tbh I'm suprised more people haven't had this option fitted.
Awesome, that's the sort of thing I was after. Do you have any reference vids for operation when the car is running? You don't happen to have a UK branch do you? Basically the valves are operated by a feed from the body control module that controls the valve making them open on cold startup.
To make it work silent you would need to take a switched feed from the ignition, that way when you turn the key to position 1 or insert the ECU key it would activate the valves making the exhaust quiet through the entire rev range.
With a 3 position switch you get three options:
Position 1 = Ecu controlled (standard)
Position 2 = Open (fuse 22)
Position 3 = quiet (Closed)
Here is a video on how it works.
http://youtu.be/3NY1sIYMkZc
Tbh I'm suprised more people haven't had this option fitted.
millsjq said:
I have a switch:
1. for Ecu controlled (standard)
2. Position 2 = Open (fuse 22)
How did you wire for the third position (quiet closed)? I am interested in the three way switch.
You need one of these switches http://uk.rs-online.com/web/p/rocker-switches/0419... then take a fused feed from the ignition, possibly the cigarette lighter, then if your looking at the back of the switch wire it so,1. for Ecu controlled (standard)
2. Position 2 = Open (fuse 22)
How did you wire for the third position (quiet closed)? I am interested in the three way switch.
Top pole (connector) ECU controlled feed (existing)
Middle pole - Feed to valves (existing)
Bottom pole - Ignition feed ( to be installed)
As you have an existing switch your half way there the only thing is the replacement is the same size or slightly larger and will fit the existing hole, if you can remove the original switch to see who it's made by they may make a 3 way switch that will fit.
kalibre46 said:
Black9 said:
Yes it is possible to do but you will need a 3 position switch (on-off-on).
Basically the valves are operated by a feed from the body control module that controls the valve making them open on cold startup.
To make it work silent you would need to take a switched feed from the ignition, that way when you turn the key to position 1 or insert the ECU key it would activate the valves making the exhaust quiet through the entire rev range.
With a 3 position switch you get three options:
Position 1 = Ecu controlled (standard)
Position 2 = Open (fuse 22)
Position 3 = quiet (Closed)
Here is a video on how it works.
http://youtu.be/3NY1sIYMkZc
Tbh I'm suprised more people haven't had this option fitted.
Awesome, that's the sort of thing I was after. Do you have any reference vids for operation when the car is running? You don't happen to have a UK branch do you? Basically the valves are operated by a feed from the body control module that controls the valve making them open on cold startup.
To make it work silent you would need to take a switched feed from the ignition, that way when you turn the key to position 1 or insert the ECU key it would activate the valves making the exhaust quiet through the entire rev range.
With a 3 position switch you get three options:
Position 1 = Ecu controlled (standard)
Position 2 = Open (fuse 22)
Position 3 = quiet (Closed)
Here is a video on how it works.
http://youtu.be/3NY1sIYMkZc
Tbh I'm suprised more people haven't had this option fitted.
kalibre46 said:
mikey k said:
Yep as I suggested permanent feed to vac pump, you will just need to leave the ignition on for a bit before you start it to allow hte pump to build vacuum.
So how much difference do you think think would make? Hard to imagine the sound with the exhaust diverted.If you watch the you tube video you can see how long it takes from him flicking the switch to the valves moving.
IIRC if you have an ECU car you will need to remove the ECU after the vac pump has closed the valves to get the start cycle to work.
This will vent the vac and put you back to square one.
This is why I suggested a switched 12V supply to fuse 22 by passing the ignition.
Try it - stick the ECU in for 10-15 seconds so the ignition runs but does not start, then try starting it with out removing the ECU.
mikey k said:
I'd guess same sort of noise as pulling away from lights? (valves closed bit of throttle on)
If you watch the you tube video you can see how long it takes from him flicking the switch to the valves moving.
IIRC if you have an ECU car you will need to remove the ECU after the vac pump has closed the valves to get the start cycle to work.
This will vent the vac and put you back to square one.
This is why I suggested a switched 12V supply to fuse 22 by passing the ignition.
Try it - stick the ECU in for 10-15 seconds so the ignition runs but does not start, then try starting it with out removing the ECU.
Sorry I quickly scanned the thread and missed your suggestion!If you watch the you tube video you can see how long it takes from him flicking the switch to the valves moving.
IIRC if you have an ECU car you will need to remove the ECU after the vac pump has closed the valves to get the start cycle to work.
This will vent the vac and put you back to square one.
This is why I suggested a switched 12V supply to fuse 22 by passing the ignition.
Try it - stick the ECU in for 10-15 seconds so the ignition runs but does not start, then try starting it with out removing the ECU.
I just watched the video again and it only took around 5 secs for the system to prime so not to much of an inconvenience having to wait that long before start.
brianjone5 said:
Tony: he is trying to avoid waking his young children ....
Correct, although if I end up with a 'stealth' switch then I'm sure the neighbours won't mind either. Conversely I'm loving having fuse 22 removed at the moment (although I've not had any early starts as yet) as I'm avoiding any proper work and just WFH. Gassing Station | Aston Martin | Top of Page | What's New | My Stuff