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Clutch switch defeated using method worthy of the HACK. :)

2135 Views 21 Replies 7 Participants Last post by  Nick325xiT 5spd
Sorry, Dan. :)

OK, following the new information we've gotten in the other thread on this topic, I thought I'd go ahead and play.

Yep, magnets will shut it off, but the car drives like shit. Not sure why.

More useful is to simply slide the switch up the cylinder a little bit. I recommend that you configure the clutch stop to your preference, then slide it up JUST enough so that you can still start the car. I used a fair amount of electrical tape to secure it in place.

The improvement is VERY nice, although it takes a fair amount of adjustment. The downside is that you notice the rev hang a lot more. Disconnecting the exhaust valve DOES seem to help rev hang a bit, HOWEVER, it is abolutely NOT worth doing. I didn't even manage to get out of my neighborhood before the noise started making me physically ill. I literally wanted to throw up. :( Needless, to say, the valve has been reconnected.

As always, your mileage may vary, I'm not responsible if your car explodes, won't start, etc. If you screw up, don't blame me.
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dude: $20 solution

ron stygar clutch stop.

ha ha!
Blackdawg, my clutch stop worked fine without modification. :) Thanks to this modification, I was able to extend it to my preferred length, which was another INCH AND A HALF out from the engine start switch's default location. :)
Uh dude....

Explain exhaust valve disconnect? Are you talking the little resonator flap on the muffler or something else? And what do you mean the sound made you physically ill?

Guess I'm just slow today cause I don't have a clue (except for the clutch switch part) what you're referring to on those two things. :dunno:
Re: Uh dude....

obLu said:
Explain exhaust valve disconnect? Are you talking the little resonator flap on the muffler or something else? And what do you mean the sound made you physically ill?
The little resonator flap, yes. And yes, it was the sound that made me feel physically ill.
Was it too loud?

Wow, I couldn't imagine just opening the little resonator flap could make it that loud? Even WOT with the top down I can barely hear my exhaust. Thought the flap was only closed at low rpm, or is it the other way around?
Hey, that's cool...At least now I can tell people how to disable that switch.

I'm surprised that it made the RPM hang. A simple switch like that, unless the signal is being inputted into the ECU for whatever reason. I'm sure we can find a way to fabricate some sort of makeshift bracket to make this mod permanent...Electrical tape just seems so...HACK.

I'm doing the SSK on Raffi's car, I may take the chance to go underneath the steering column to see the switch and see if anything can be fabricated.
Re: Was it too loud?

obLu said:
Wow, I couldn't imagine just opening the little resonator flap could make it that loud? Even WOT with the top down I can barely hear my exhaust. Thought the flap was only closed at low rpm, or is it the other way around?
Above 2500RPMS, the car sounded great, actually. But you know the deep, deep basso rumble that you get at part throttle at low RPMs? Imagine it multiplied a hundred fold.
The HACK said:
I'm surprised that it made the RPM hang. A simple switch like that, unless the signal is being inputted into the ECU for whatever reason. I'm sure we can find a way to fabricate some sort of makeshift bracket to make this mod permanent...Electrical tape just seems so...HACK.
There has always been rev hang on my car. Less clutch travel just makes it a lot more noticable. As I said earlier, disabling the exhaust valve (present only on 330s and 325xis) seems to reduce rev hang. It just wasn't worth the cost.
Uuuugh.

Yeah, I can see why that would make you ill....
Nick325xiT said:


There has always been rev hang on my car. Less clutch travel just makes it a lot more noticable. As I said earlier, disabling the exhaust valve (present only on 330s and 325xis) seems to reduce rev hang. It just wasn't worth the cost.
You know WHAT would be worth the cost? SHARK INJECTOR. I've noticed that the Shark significantly reduced the rev hangs on my cars.

End of the year is the latest rumor. Hopefully Jim C. will hit that.
If it really cures rev hang and fixes throttle lag, I will buy one. Instanter.
Out of curiousity, does Active Autowerke have the Jim C software? I know that they used him in the past, and I have to wonder if they're just selling the conforti chip without the injector (for ludicrously high prices).
Oh, one other thing... Cutting the BROWN wire (at least, it was brown in my car) had the same effect as attaching a magnet. Mind you, I didn't actually cut the wire, it broke. :( The cables look as if something chewed on them a bit. :mad:
Nick325xiT said:
Oh, one other thing... Cutting the BROWN wire (at least, it was brown in my car) had the same effect as attaching a magnet. Mind you, I didn't actually cut the wire, it broke. :( The cables look as if something chewed on them a bit. :mad:
[Spock]Fascinating.[/Spock]

What this means is that it shouldn't be too hard to "splice" into that wire and then run the connection to under the dash and install a switch. This way, instead of pushing in the clutch to start the car, you reach under the dash and hold down the switch. This creates an open circuit, just like the broken wire, and the DME thinks the clutch is depressed. Of course, you'll have to be careful and make sure the care isn't in gear when you go to start it.

Hmmm. While moving the switch on the cylinder is the more elegant solution, installing the under-dash switch appeals to the hacker in me. :)

Edit: It occurs to me that installing the under-dash switch may affect how the car acts as the DME is obviously affected by the clutch being depressed.
I don't believe that this would affect the car. Just open the circuit to start the car, then close it afterwards. The car felt fine with the circuit closed and detached from the cylinder aside from the minor detail involving starting it.

Shifting is much more relaxing now, though. That's for certain. I depress the clutch and wait for a moment before letting it out again. The old setup required very careful coordination to manage a smooth shift. It was just FAR too easy to let the clutch out late.
You wouldn't happen to have taken some pictures...
Not yet, but I'll be sure to do so this weekend. :)
Well, Rob posted his findings and pictures

here...
Hmm... There is that method. The downer is that that requires rather more substantial work. I'd be awfully concerned about doing that myself.
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