JackOlsen

I'm posting this here because I figure racing steering wheels are the most likely to have additional buttons on them -- like for a radio.

I wish I could get a better look at the whole column and assembly to see if this is straightforward, impossible, or somewhere in between. But I want to put a switch on my steering wheel, which will run to ground (like the horn). I'm willing to lose my horn functionality if I need to, but I do not want to use the sliding plunger contact and ring that the horn uses, since it doesn't give me reliable enough contact when the wheel is turning/flexing/shaking.

Has anyone done this? The goal is to have a wire provide ground to a relay (in this case, it's for my active rear wing). It's for a 1972 911 steering column.
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jscott82

For something as mission critical as active aero, I would want a hard wired connection like most use for the PTT switch.

If you want to hide it all in the column, take a look at some of the airbag connectors. The one in the 993 (and I assume all/most others are the same) is a hardwired ribbon cable wound like a spring.

Tom W

You want to use the stock wheel or with an aftermarket wheel?

I have a Momo wheel that came with 2 buttons and added more for the radio and MoTeC. No wiring goes through the column it's an additional wire (or wires) that then connect from the panel area to the detachable wheel. You can see the coiled wired hanging in this photo. It's a thin CF plate that is used to mount the extra buttons.

But I'm guessing that you are looking for a 'stock' solution ...

JackOlsen

Thanks.

I've got an aftermarket wheel, and it's removable. I was hoping to be able to avoid using a coiled line. But I have some of it, and maybe it's the best/safest solution to this.

Tom, you found a way so that the coiled line stretches enough for turning and puttiing the wheel on the hook, but not so much that it drapes down on your legs?

Matt Romanowski

You could do something like this https://www.pegasusautoracing.com/pr...sp?RecID=10448 which Scott will love.

Or do it the cheap way. For one button, get a curly cord and put a couple wraps around the column when you put your steering wheel on.

winders

Is that a push to pass button, Tom?

Tom W

Jack: I have two coiled wires (historical reasons) and they have a cable tie that attaches them to the hub so they don't hit my legs and it allows enough stretch to get to the hook without an issue. I'll try for a couple more pics to be clear.

Matt: Nice, but not cheap!

Scott: PTT is push to talk. The "advance" button is the one to magically get me in front of you or Gary. The "Back" is obviously not connected. In reality, the left red button is the MoTeC "next screen" (there are 3), right red is MoTec "alarm cancel" and general reset (as programmed) and the "Back" and "Advance" are for the MoTec dash screen to go to different display lines.

Tom W

Here's a shot that shows the low tech attachment to the hub that makes it easy to adjust the way the wires hang and ensure it can reach the hook.

winders

That's pretty cool. I was thinking the "Advance" button was the push to pass button. One of these days I am going to add a radio system to the car. That way Monica can tell me what the heck is going on around me on the track.

Monica and I are looking forward to seeing you, Stephanie, Olivia, and Lucy at the first PRC event at Sears Point in March. See you soon!

JackOlsen

Thanks, Tom!

I've got turn-signal and windshield-wiper stalks to work around. But I think I'll be able to make it work if I do the same thing.

What's frustrating is that the threaded shaft for the steering wheel is hollow on my car. But I can't get to an exit point in the linkage without (I think) tearing everything out. Since I might easily abandon the idea of the drag reduction system, it seems like simpler will be smarter.

Tom W

Scott: Looking forward to it. I should finally be doing my test/coaching day with JvO on Tuesday. We'll see if I can give you a bit more trouble after that. I'm hoping to get Johannes and Craig to help with the setup (more mechanical grip) 'cause I lose most to you or Gary in 6, 7 and 11.

JackOlsen

Well, I found a way to do it that didn't involve a hard line connection to my steering wheel.

Of the two junction points in the horn's electrical path, the one for the horn that is a part of the quick-release could not be made to fail. I have conductive grease on the contact point(s) as insurance.

That conductive grease is messy.



The horn contact in the column that rotates a sprung piston around a little copper track was the one that could be made to fail intermittently, so I'm not using it. Instead, I have a length of coiled wire (a guitar plug-in line) so that there's enough slack to wrap when the wheel is turned. The switch is a push-button type that I mounted in one of the steering wheel holes. It has to be held down, which gives me a form of 'dead man' protection. As soon as I let go, the wing goes back to the high-downforce position.



I'll test it later this month.

Krokodil

Please be careful Jack:



Cheers,

PPo

I may be missing something... but I would prefer doing it right with something like this:

https://www.pegasusautoracing.com/pr...asp?RecID=3139

High quality quick release with an 8-pin connector built-in... The price is not that bad, IMHO, considering the alternatives...

JackOlsen

Yep. I've seen the Schumacher video. I'm not using it at any track with walls. And the aero on a car like that is worlds apart from mine in terms of the concequence of the wing sticking in the low-downforce position. I've gone out with it in the low-downforce position for entire laps -- and even did a session early on where I was unwittingly putting it in the low-downforce position when I belived it was going to the high-downforce position. It was a little squirrely, but still manageable.

My car's aero is so vague and sloppy that the effect is just not very dramatic. At best, I might get another 1-2 mph at the end of a long straight.

But your point is well made. Anything that makes you more likely to crash has to be scrutinized pretty carefully -- and adding complexity is always something you want to be cautious about.