Horn schematics?

[Palting 996 C4S]

I just bought a 150dB compact air horn. Blast those darn SUV's off the road, heh-heh :cursing: .

Has a relay and need to get lots of watt power. Anyone have or know where I can get schematics for the power source?

Edited July 17, 2005 by Palting 996 C4S

[Loren]

What year car?

[Tool Pants]

I added air horns to the existing electric horns. I did not run a separate circuit with a relay and fues for the compressor like you are supposed to. Instead, I hooked into the existing electric horn circuit.

So all the horns run off the original relay and fuse. The first time I pressed the horn pad I expected to blow the fuse or fry the relay since there are 2 high amp devices on the same circuit. All I got was a lot of sound. Been 2 years this way with no problems and I do use my horns.

Since I did it the "wrong" way I only needed to run a ground wire from the compressor to a ground lug in the front trunk, and the positive wire goes to the wire from the horn pad which is in the white 21 pin connector next to the brake booster.

Ths was on a 986.

[Palting 996 C4S]

Thanks, Loren and tool pants.

This is for either the 2002 C4S or the 2005 987S. I found the wiring diagrams for the 2002 C4S. Guess I can just hook up the compressor in sreies with one of the electic horns and keep my fingers crossed hoping all goes well like with tool pants..

Edited July 18, 2005 by Palting 996 C4S

[Loren]

The stock two-tone horn is on it's own 25A circuit so you could always bump the fuse up a little.

[bigbadjohn]

I added air horns to the existing electric horns. I did not run a separate circuit with a relay and fues for the compressor like you are supposed to. Instead I hooked into the existing electric horn circuit.

So all the horns run off the original relay and fuse. The first time I pressed the horn pad I expected to blow the fuse or fry the relay since there are 2 high amp devices on the same circuit. All I got was a lot of sound. Been 2 years this way with no problems and I do use my horns.

Since I did it the "wrong" way I only needed to run a ground wire from the compressor to a ground lug in the front trunk, and the positive wire goes to the wire from the horn pad with is in the white 21 pin connector next to the brake booster.

Ths was on a 986.

ToolPants,

Where did you mount the air horns on the 986? I've gotten a set for mine to replace the originals. Looking for a starting point.

Thanks,

John

[Tool Pants]

The horns and the compressor are on a metal bracket behind the bumper cover where the third radiator would be ( I have a 2.5). My car was backed into by a truck. When the body shop was ready to put the new bumper cover on I took the car home for the weekend so I could figure out a good mounting place. Then on Monday the shop put the cover on.

I had thought of putting the compressor in the trunk but there is a lot of room behind the bumper cover. Plus the compressor is sealed so you do not need to put oil in it like the old days. So the compressor went on the same bracket as the horns.

I took pictures but I will not have my computer for a few days.

[bigbadjohn]

Thanks TP,

If you don't mind posting the pics when you get a chance, I'd appreciate it.

John

[Tool Pants]

I used an angle bracket leftover from when I put in a garage door opener. Angle will not flex like a flat bracket and the compressor is heavy. Compressor and horn are bolted to the bracket.

I then bolted the bracket to the mounting points for the third radiator. I did not want any of the nuts backing out over time because I would have to pull the cover to retighten them, so I used lock washers and loctite on the bolt threads.

There are 2 rubber gromets so that you can run wires from the compressor into the front trunk. I poked a hole in one of them and ran the 2 wires for the compressor into the trunk. In the 3rd picture you can see the gromet I used and the red and black wires for the compressor.

Here are how others have done it.

http://homepage.ntlworld.com/salterma/index.htm

http://www.renntech.org/forums/index.php?showtopic=7587

[Tool Pants]

There are a number of grounding points in the trunk for the negative for the compressor. You will see a nut with brown wires under the nut. That is ground. In the 3rd picture there is a yellow line to the grounding lug.

For positive to the compressor I added the wire from the compressor to the existing wire to the electric horns. There is a white 21 pin connector next to the brake booster and in the connector is the horn wire. With a pin removal tool I removed the wire and soldered the new wire to it - then put the pin back in the connector. The 2nd picture shows both wires soldered together. The red wire is the positive to the compressor.

When you look at the 3rd pic you will see that the red wire has been coiled up and tucked away. I left it long because my future plan was to bring that wire to a dash switch next to the radio, so I could select oem horns, air horns, or all horns. I later decided not to do the switch. The reason for the air horns is that a big truck in front of me at a stop sign backed up and hit me so fast I would have had no time to play around with a switch.

[bigbadjohn]

Thanks for all the details TP! I can't get to it till next weekend, but I'll let you know how it goes.

John

[bigbadjohn]

Finally installed the horns yesterday (and cleaned my radiators while I was in there). Great mounting idea TP! For the mounting bracket I used a piece of a leftover steel shelving leg. Since I was taking out the stock horns, I spliced into those wires for power. All kinds of loud now. I don't like the slight delay, but I'll get used to it.

Thanks again,

John

[Tool Pants]

Can't avoid the delay because the compressor has to kick on. The Boxster is the 4th car over the years I have owned that I put air horns on. The delay in the Box air horns is very slight for some reason compared to the other cars. Since I retained the oem electric horns I like the delay. If I tap the horn (like when the light turns green and the car in front just sits) you hear just the electric horns. If I hit the horn harder then all horns come on. This is another reason I decided a switch was not necessary.

Next time I'm going to try these horns sold by Griots. Very compact unit since the compressor and trumpets are packaged together. With all the room behind the bumper cover I can mount several sets of the horns. But then I might need a switch to reduce the number of horns that come on. http://www.griotsgarage.com/catalog.jsp?&SKU=77839

[adsach]

Can't avoid the delay because the compressor has to kick on. The Boxster is the 4th car over the years I have owned that I put air horns on. The delay in the Box air horns is very slight for some reason compared to the other cars. Since I retained the oem electric horns I like the delay. If I tap the horn (like when the light turns green and the car in front just sits) you hear just the electric horns. If I hit the horn harder then all horns come on. This is another reason I decided a switch was not necessary.

...

What is the Brand and model on your 'slight delay' air horns?

[Tool Pants]

I have spent some time in Boston traffic because my brother has lived there for years. Horns ain't going to help you as the drivers are not only blind, but deaf.

The Italian company Fiamm has a monolopy on the air horn market. I bought Fiamm Riviera from a local parts place. I think Pep Boys. I looked at Kragens, Autozone, and so on, and was seeing the same horn repackaged under different names.

I just tried the my horn. The delay is very, very slight. I do not know if the compressors have improved over the years or because the hose from the compressor to the trumpets is so short due to the way I mounted them.

Keep in mind I would have had to mount them differently if I had an S, but even with an S there is a lot of room behind the bumper cover.

[bigbadjohn]

I went the Harbor Freight route and bought a set that was on sale for around $13. I've been using them daily, there is almost no delay now. I think the cheap compressor just needed to be broken in. Time will tell whether it was worth it or not. Of course the stock horns only lasted 7 years :-(

[stumpjumper]

so last week I'd bought the Hella dual horn air horn for installation this past weekend since one of the two stock horns was dead (4 years 9600 miles, wtf?)

my wife was none to pleased with the idea of an air horn and since she does own half of it we compromised by returning the kit and buying the Hella Compact Trumpet horns which are a direct replacement for the stock horns except for the wiring harness

now these horns are only rated at 110db but still considerably louder than stock and definately gets the attention of the Boston area drivers that I commute with every day

of course the air horns will be considerably louder, 8db is a big difference, but these at least have zero delay

part of me still wants the air horns but these were so damned easy to install that I figure it was a good compromise

[Tool Pants]

If your car comes home one day looking like this maybe your wife will change her mind about the air horns.

Especially if you tell her the front is her half when a truck backs up into you. :lol:

[stumpjumper]

If your car comes home one day looking like this maybe your wife will change her mind about the air horns. Especially if you tell her the front is her half. :lol:

I actually showed her your pictures before we went to the store to exchange them, she figures that if the guy doesn't stop with the 110db horns he's not going to stop with the 118db ones :)

[buster356]

I just added Hella Air Horns to my 2003 Boxster S. They fit just like in Toll Pants photo's except you need to angle them so they clear the center radiator. Sound is loud but I am having trouble getting the wire out of the 21 pin connector. Does anyone know where I can get a pin removal tool or what size I need?. My local dealer does not stock tools.

thanks :cheers:

[buster356]

Sorry Tool Pants, messed up your name!

[Tool Pants]

http://www.renntech.org/forums/index.php?s...mp;hl=Sir+tools

Others have also said the Sir Tools version has been discontinued, but it is still shown on the Sir Tools site. http://www.renntech.org/forums/index.php?s...mp;hl=Sir+Tools

http://www.sirtools.com/more_asian.htm

The place where I bought mine years ago does not have it listed anymore.

[buster356]

Thank You!

The hunt is on......

[Chuck Jones]

Loren and I got together and installed the Griot's "Italian Air Horns" which have a db rating of about 130. I did the install much like ToolPants using the third radiator brackets....Loren has a third radiator so his install was slightly different.

These horns have built in compressors and relays and wire right in to the existing wiring. The neat thing is that they're so compact, self-contained, loud, and only cost $39.95. Go to the www.griots website and put in Italian Air Horns in the search block....take a look, I think you'll like what you see. I have them in both the 996 and the 930 and really like them.

Edited August 5, 2007 by Chuck Jones

[gandrade1]

Finally installed the horns yesterday (and cleaned my radiators while I was in there). Great mounting idea TP! For the mounting bracket I used a piece of a leftover steel shelving leg. Since I was taking out the stock horns, I spliced into those wires for power. All kinds of loud now. I don't like the slight delay, but I'll get used to it.

Thanks again,

John

I am also removing the stock horns and replacing them with an air horn kit on my base 986 (MY01). Based on ToolPants postings I found a place to mount the horns and learned how to secure them.

I have no clue on how to run the electrical connections, however. I would like to keep the electrical connections very simple since all I know is that I need to get a positive wire and a negative wire to somehow connect to the back of the compressor.

Can anyone please clarify which wires to splice - I was hoping I could just use the positive and negative connections that run to the back of either the low/high OEM pitch horn and connect them to the back of the compressor. I am planning on simply covering with electrical tape the two terminals that go to the OEM horn I will not use.

Simply, my questions are:

1) Can I just splice the two OEM horns, isolate the terminals that go to the back of one of them and use the other 2 to connect to the compressor?

2) From the pair of terminals I choose, how do I know which one is the negative and which one is the positive? Are they color coded?

3) Since I am mounting the compressor in the center of the bumper (where the 3rd radiator would be) I need the terminals to reach there, so I am simply planning on buying regular 16 gauge wires and running from the original terminals to the center of the radiator - How do I secure my connections? Can I just use electrical tape and 'crimp' the connectors that go to the back of the compressor?

PS: I dont have a soldering machine...

Sorry for the many and most likely obvious questions...

Best,

Gus

Edited May 8, 2008 by gandrade1