Shifter mounted manual idle/ cruise control

[fowljesse]

Okay, it's time for another crazy idea from Jesse!
My car revs/ drops back to idle pretty fast, and will be more extreme when I get the rest of my parts in. I don't want to do the heel/ toe thing, so I thought of this:
I'm thinking about putting a bicycle shifter lever on the shifter shaft that would have a cable that goes to the throttle cable at the gas pedal. On the throttle cable, there would be a piece crimped on as a stop, and the other cable would slide on the throttle cable until it hit the stop. That way, I could freely move the throttle cable with the gas pedal, and when I let off, it wouldn't go back down past the set [idle] point. This way, I could set the idle at, say 3,000rpm when I'm autocross racing, 4,000 for drag, or 2,000 rpm for daily driving, and 600rpm sitting still. Also, I could set it at 3,000ish rpm as cruise control, and then I could get rid of my ECU (Since I have MegaSquirt).
It may sound scary to not have an automatic cancel for cruise, but I've never used it. I always cancel it manually, and since people are generally stupid, I have to adjust the cruise speed constantly.
Also, I got a new condition steering wheel form an RS, so it doesn't have the cruise buttons.
This idea would also work for a manual exhaust cut-out.

[Mi|<E]

Or instead interrupt the IAC valve signal and change your idle rpm settings electronically...

[fowljesse]

That sounds interesting.
However, I have no IAC. I thought the IAC was manual (A piece of wax heats up, and closes the extra air intake).

[_-Night-Shade-_]

Sorry but what do you mean by "the heel/toe thing"? The only heel & toe I know of is the down-shifting/rev-matching while braking technique, and I don't see how that relates to what you're saying.

[fowljesse]

Yeah, that's the thing. I've done it while autocrossing, and I'd rather not.
Also, I have to shift very quickly every time, or the rpms drop back to idle, and with solid motor mounts, and torque damper, it gets annoying, because if it's not rev-matched, it jerks a bit, and rev-matching is difficult, because if I'm too high, even a little, the car jerks forward. This will get more pronounced when I put in a stronger clutch.

[Sleeper6]

Im not sure if we have anyone with the capability but the new 370z's automatically rev match by way of the computer and tps when you downshift, Im not sure if anyone could design a servo that could work in conjuction with a piggyback ecu to controll this but just an idea

[fowljesse]

That would be sweet! I imagine that they have an electronic throttle to start with, which would make it easier.

[_-Night-Shade-_]

Are you kidding me? Jesse sorry to be harsh, but instead of spending time thinking up some contraption you should be spending time practicing heel & toe. The whole point is to rev-match, and when you down-shift the RPMs are gonna be higher than what they were so you know you'll have to use the throttle anyway. And it really doesn't matter what setup you've got, this technique is to eliminate the jerkiness with any car while down-shifting, solid mounts or not. I don't think you'd wanna be fiddling around with the cruise when you're autocrossing anyway, and honestly, I'd rather be able to have the skills to do this myself than have the car do it for me.

[Sleeper6]

I love shifting techniques as well but honestly we all have our lazy moments when its not a top priority and I think its just plain brilliant if I can qoute top gear as they drove the 370 zed lol.

And as for me personally its sitting in rush hour traffic shifting from first to second to first to... that a mod like that would be awesome on a high strung car.

[fowljesse]

I understand where you're coming from, _-Night-Shade-_. I can rev match, and have, but prefer not to as much. I had pedals in my RX-7 that were closer together for this porpose. The higher idle would get me closer to the the rpm, so I'd just have to blip it. Rev-matching is much more difficult with a touchy throttle, and an engine that doesn't move. I can easily do it in the stock car. Also, like Sleeper6 said, it's alot better in traffic. I had my throttle stuck at about 1Krpm until recently, and it was actually nice, because I never had to touch the throttle in rush hour. If I wanted to, I could get all the way up to 5th that way, and cruise (slowly, of course).
This wouldn't have anything to do with cruise control, it would just set the idle wherever I want it.
Also, I came up with the idea in about 10 minutes. I used to race mountain bikes semi-pro, and worked on them alot. My expertise in various shops was dialing in shifters, and brakes.

[Tollis]

Why don't you try side stepping. It's mostly a drag shifting technique but would work for what your explaining. You put just the side of you foot on the clutch and let it slide off the side so it kinda pops the clutch while you quickly shift at the same time. The clutch isn't depressed for more than a second or so and won't lose many revs