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"Train Horn" on Model S

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Hi Folks,

A few weeks back, I installed a 4 trumpet air horn on my Model S. Why? Because the factory horn doesn't seem to be loud enough to get folks' attention when they are about to cause an accident.....and this has definitely solved that dilema.

I've received a bunch of PMs about it, so figured I'd share details here to avoid copying and pasting.

Below is a picture, followed by a parts list and explanation:

IMG_1019.jpeg


As you can see, this is all contained within the frunk of a Dual Motor car. The horns and tank are mounted to the bottom of the tub (no rattles or vibrations).

The kit is a Hornblasters Bullet kit with a 2 gallon tank. There is a smaller kit with a 1.5 gallon tank available as well.

I did buy two extra parts, a 90 degree 1/2" push-to-connect fitting for the tank to prevent hose kinks, and a 30a resettable circuit breaker so I can turn off the compressor if I want:

horn/compressor kit: Bullet 228H Air Horn Kit

air fitting: https://www.amazon.com/gp/product/B08734HVKT

circuit breaker: https://www.amazon.com/gp/product/B077CZJRN5

For activating the horn solenoid, I tapped into one of the factory horn connections (which are right in front of the frunk tub)- so the factory horn still works as well. I put a weatherproof connector on this, so if I want to kill the air horn I just pull that connector off.

I hard-wired it to the 12V battery right behind the frunk. I grounded it using the frunk bolt to the frame, which worked great. I put a 30a circuit breaker and a quick disconnect on the hot wire so I can just pull the whole frunk out if I want to remove it for taking to the Service Center or something. Since the car automatically recharges the 12V battery off of the main pack, it does not pose a risk of killing the battery....and if you don't have any leaks, it should only activate for 1 minute after a long horn blast at a maximum of 23 amps.

I also removed the frunk gasket to allow the air to travel and let the noise get out a bit more easily. I've driven in heavy rain, no water or dirt has gotten into the frunk without the gasket.

Functionally, this is loud as hell. I don't use it like a jackass to scare people, only as a quick "stop doing what you're doing" notice to those around me. It has been much more effective than the factory horn at getting attention for that. I get about 6-8 seconds of continuous blast, and the air compressor fills the tank back up in about 1 minute.

I'll post a video later, once I can get away from my densely populated area.

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On a side note, you could absolutely tap into the factory air suspension tank, which is behind the 12V battery, rather than using a self contained tank/compressor. That would allow you to fit a bigger horn or just take up less space in the frunk. You'd just remove the Schroeder valve fitting on top and replace it with a 90 degree, 1/2" OD push-to-connect fitting and run the air hose down to the tub. With that said, you do that at your own risk. Not to say it'd break anything, but a Service Center wouldn't like seeing that the reserve tank was being used in that way.
 
Those do give off some pretty loud sounds however if money is not a factor, here is another option. Have a set on our boat, scary loud and actually sound amazing. Same small compressor can be used as you have. Did have a compact triple set prior however the Kahlenberg horn is far superior in every way. Got to hear them to understand. Just got frustrated with boat horns as they are quite necessary at times however with ambient noise in boating you cannot hear them unless at idle. This solved that and then some. Model D-0A Air Horn (Horn Only), For Boats Less Than 65 ft., (20 Meters)

How muffled is it being in a closed frunk?
 
Those do give off some pretty loud sounds however if money is not a factor, here is another option. Have a set on our boat, scary loud and actually sound amazing. Same small compressor can be used as you have. Did have a compact triple set prior however the Kahlenberg horn is far superior in every way. Got to hear them to understand. Just got frustrated with boat horns as they are quite necessary at times however with ambient noise in boating you cannot hear them unless at idle. This solved that and then some. Model D-0A Air Horn (Horn Only), For Boats Less Than 65 ft., (20 Meters)

How muffled is it being in a closed frunk?

That’s a good sounding horn there. Definitely out of my budget for this project, but it has a great tone.

It’s not muffled at all by being in the frunk…still exceptionally loud, especially compared to the stock horn.