Clutch Pedal Switches

[l1ttle_d3vil]

Looking at options for switches to mount on the clutch pedal for launch control / flat shifting.

Originally had a generic brake pedal switch but this didn't provide enough travel as the "piston" only moved about 3 or 4mm, hence the switch engaged basically as soon as the pedal moved but the clutch didn't engage after another inch or so of travel.

I could wind the switch in so it engaged the same time as the clutch, but then it was basically holding the clutch pedal halfway down the whole time hence "riding" the clutch constantly...

What does everyone else use? Been to repco / jaycar / auto sparkies and none of them have anything definitely suitable.

Cheers
-Matt

[MrOizo]

Could you have something steering wheel mounted and control with thumb?

[captain crescent]

how about a motorcycle rear brake switch like so.


This way you can just tension the spring to get it to activate where you want it.

[Bazda]

I just use the alarm bonnet pin switches from Jaycar.

They are a threaded body and quite long so you got heaps of adjustment.
They are thinner than a 12mm hole so it slides straight inside the stock hole.

Then you just use locking nuts each side of it. Plus they pins have heaps of travel.

[Quint]

What you want is a limit switch, they come in all shapes, all sizes, am surprised jaycar didn't have anything suitable? Maybe you wern't asking the right questions eg 'where the limit siwtches at!':)

[stolic]

Have you got a pic of how you have it set at the moment?

You could try mounting the switch closer to the hinging point of the clutch pedal, as the closer to the hinge, the more travel you'll have at the actual pedal before activating the switch... ie the actual pedal may move 3-4 inches.. but up near the hinge that may equal only a few mm.

or you could try mounting the switch in a manner that lets it "float", using something like a bit of steel tube as a sleeve with a spring in it




or you could mount the switch on a swing arm with a keeper spring, allowing it to follow the clutch pedal after the switch is engaged




I'm sure there are heaps of other ways, but I hope that helps

[stolic]

Or just ignore me doing things the hard way, and do this instead lol

I just use the alarm bonnet pin switches from Jaycar.

[blindnz]

Retard question..

So what do you wire the other end of the switch into?

[Bazda]

Earth.

The switch just completes a circuit.
When earthed (pedal engaged) the circuit is earthed as the switch is mounted to the body of the car. When clutch is out it dis connects the circuit.

The other drawing above is far too difficult. The switch has tiny amount of throw. And they usually work the other way around in terms or circuit.

I used one of these http://www.jaycar.co.nz/productView.asp ... rm=KEYWORD

But the plastic pin version. Cant remember why I choose the plastic one. Had something to do with the dimensions.

[l1ttle_d3vil]

Thanks for the suggestions.

Steering wheel switch - would work but probably too hard to switch it at the exact point, not just for launching but flatshifting too.

Motorcycle break switch has been suggested by an autosparky, but surely there's easier ways to set it up!

Limit switches, probably same as above - would work but a lot of work to setup right.

The clutch pedal already has a thread / nut fitted (might originally have been a brake pedal) so basically all I need is a switch with the right adjustment / travel.

I had thought about an alarm tamper switch, but the thread was wrong. For some reason never even thought of using 2 nuts to lock it I think they have about 12mm of travel, which should hopefully be enough. Will track one of these down and see how it fits up.

Other end of the switch can be wired in to anything, earth or 12v, just as long as it switches at the exact point the clutch engages/disengages so the ECU can recognise the change. If it switches too early, the car is trying to move while the ECU is still limiting the revs for launch control...

[blindnz]

Other end of the switch can be wired in to anything, earth or 12v, just as long as it switches at the exact point the clutch engages/disengages so the ECU can recognise the change. If it switches too early, the car is trying to move while the ECU is still limiting the revs for launch control...

This is what I wondered. I figured it must go to fuel/ignition/something to stop it revving. I just didnt know ECU's had an input for flat shifting.

[l1ttle_d3vil]

Link ECU does Won't find one on your factory ae86 ecu though

Basically its all setup using the pclink software, everything is adjustable but for example -

For launch control, you set it so once the clutch pedal is held in for more than 2 seconds, the launch control engages. This is basically a rev limit of 4000rpm. The 2 second delay in this engaging prevents it from limiting the revs every time you push the clutch to change gears. You can also set it so once launch control is active, if the throttle is over 70% it will adjust the ignition timing to create boost off the line.

For flat shifting, it simply cuts the ignition signal for a specific amount of time to allow you to change gear and let the clutch back out, while keeping the throttle wide open. Good for 2nd / 3rd / 4th gear, but 1st is a bit sticky to get in to sometimes This can be set to only operate if the revs are over 5000rpm, and throttle is over 70% open too. So if you're cruising around town, you can change gear like normal without it cutting the ignition signal.

Stupid thing is the hardest part of the puzzle is finding a damn switch to suit!

[Dell'Orto]

You've tried this type?


Both Jaycar and Dick Smith do various versions of these

[Bazda]

You've tried this type?


Both Jaycar and Dick Smith do various versions of these

That wont work, not enough travel.

I looked at all options when doing mine 6 years ago!!!
Since then I install the bonnet pin switches into all my mates cars.

Cheap and takes 2 mins to install.
Worked flawless for me over 100+ drag passes flat shifting every time.

[XS1V]

I have 100's of bonnet pin switches if anyone needs them, basicly free

Brad