Cadillac Horn Mod

[86VickyLX]

fun fact, 2 of the delco remy horns are the same tone as the stock horns. So realistically, you only need to mount 2 of them. I would strongly recommend upgrading the horn relay.

[GM_Guy]

The Declo-Remy four note horns arrived this morning - yay!
3. Any other useful tips or advice would be most welcome!

I highly suggest mounting them in a more protected location. My '83 truck has (had) the factory horns behind the grille, they get water in them and that kills them. The stock horn location in the box is what I would call almost ideal, the fender acts as a speaker or sorts and adds some body to the sound. I moved my truck horns to the front fenders behind the headlights (one on each side) in the engine bay and it has a much better presence when you need to sound the horn, especially noticable when having to alert idiots trying to lane change into you as the horns now beside them instead of ahead of them. Forward alerting is not negatively affected either from my observation, that presence seems to be more pronounced in a wider path.

[TheEnglishChap]

fun fact, 2 of the delco remy horns are the same tone as the stock horns. So realistically, you only need to mount 2 of them. I would strongly recommend upgrading the horn relay.

Electrics is my weakest point... so please excuse my lack of correct terminology...
I believe my horn relay is on the driver's side, close-ish to the horn itself. It is below two larger ones - is this the relay I need to upgrade? If so, with what exactly.
With thanks!

[sly]

Yes, that's the one. If the wires are still in good shape, You can probably just leave it alone. If the insulation is shinking back and exposing wires, it should probably be replaced (harness and all) and might as well put a standard Bosch style relay (generic ones you can grab off the shelf in a parts store) in so you don't have to source the Ford specific ones. The circuit itself should handle the new horns. I think it's a 10A circuit. If the package says anything about how much current draw the horns have, compare that. If it's more than 10A, you'll need to run another relay. If it's less then or equal to 10A, you're fine. And this is the "peak" value if they have that listed.

[TheEnglishChap]

Sadly Sly, there is no information on that. The fellow just sent them. I will figure out somehow to run a draw test on each horn to check this.
If I was to end up getting a new relay, what exactly would I need. A quick look for (bosch) horn relay on napa and rockauto, but nothing matches.
And of course there is nothing in the workshop manuals I have about the relays (or else I am not creative enough to work out under which section they would fall under.
For the OEM horn testing in the book, the amperage should be 5.5A per horn. Does that mean the relay is higher than 10A?

[sly]

The relay should handle 20-30A. The circuit I think is fused at 10A. From what I remember, I think my 88 had a draw of about 4-5A total.
The universal relays should be rated for 30A. You can run a fused wire from the battery using one of those inline fuse holders and install a 15A fuse to a relay and then trigger that relay with the stock horn button.

you can read up on this stuff here: https://www.the12volt.com/relays/spd...ive-relays.asp
the 12 volt .com is a good source for beginners and experts alike.

Check the ads at the bottom of the page and buy a pack of relays with the wire harness and that will make it much easier to swap in.

[TheEnglishChap]

Sly, to make sure I comprehend you...
From +ve battery terminal use an inline fuse to the relay, then keep the original wiring from the relay to the horns.
What gauge wire should I use for the in-line fuse?
This is the in-line fuse I am looking at getting today...
https://www.napaonline.com/en/p/BK_7...pressionRank=1
As for the relay... I will speak with my NAPA store and see what they have.

[sly]

If you go a new relay route, just use the horn button input to the original relay and run your own to the new stuff.
Pretty much yes, that fuse holder. Use that same gauge wire or 16 gauge and you'll be fine. Run the fuse at the battery (starter solenoid - battery side), then run wire to the relay common, then same wire from the normally open on the relay to the horns. Then just run some wire to ground the other side of the coil on the relay that the horn button wire will go to.

Quick paint diagram:

[TheEnglishChap]

I would like to thank everyone in this thread for your support.
Installed the ACDF horns - sound epic!
Here is where they are located:
One in each of the original location, and the other two close by behind the headlights.
No additional drilling needed (fortunately!).
Had to cut off part of the horn mounting bracket to fit, but other than that, no major work needed.
Used an inline fuse holder, with a 30A in it.
Original relay kept.
Mounted each of the four ground wires to the body. Positives linked together using the original connector from both sides.
One of the easiest things done to the car.
Sounds a peach!

[Lutrova]

Good to hear it was such an easy install. Could you post a picture of the holes you used to mount through?

[sly]

I would reduce the fuse to 15 or 20 as the 30 will not protect the wires. The wires are too thin and will fuse first before the fuse would blow.

[TheEnglishChap]

I would reduce the fuse to 15 or 20 as the 30 will not protect the wires. The wires are too thin and will fuse first before the fuse would blow.

I used a 20 and it blew that!

[TheEnglishChap]

Good to hear it was such an easy install. Could you post a picture of the holes you used to mount through?

I will have to get photos when it is a little cooler. Shocked to say it is in the low 90's out here in WA today... where it was miserable two weeks ago.
I should have taken photos throughout the install!

[massacre]

Glad to hear you got them installed

[sly]

I used a 20 and it blew that!

Wow. You might need to upgrade the fuse holder and wire then. 30 amps needs 10 gauge wire. You might get by with 16 for a while, but if you use the horn for more than just a quick toot, you may fire the wires.