Less perminant throttle control cruise

[Kobushi]

I've been wanting to do a throttle contol mod, but I don't want to drill or damage any components that would make it hard to return to stock, or that would look cheapo.

So I've been trying to think of some sort of 12v actuated clamp that at the push of a button would grip the throttle cable, then it could be wired to turn off with brakes.

At the same time, usine the S2000 cruise control switch, one could make the 2nd button a brake regen button, so you'd have 2 buttons to turn on/off the throttle control, and one also functions for max brake regen.

Anyway my problem is in locating an already-made part which can grip the throttle cable. (grip when it has 12v to it, release when no power)

Any advice?

--Ash

[Mike Dabrowski 2000]

Kobushi
I have been thinking about that also for some time. There are several approaches that can work, but none using exclusively off the self parts.

A 12V solenoid would seem to be the easiest. The soenoid plunger could have a slot in it that the throttle cable passes through. The plunger would be held almost fully into the coil, by an adjustable prepositioner, so there would only be a short motion to clamp the cable. The rest is a simple latching relay that is unlatched when the brake is pressed, to release the throttle. Now add a short stroke servo stage to move the solenoid, and we have a MIMA throttle control for the electric cruise control.

[Lawson Huntley]

This is something that I've given quite a bit of thought to as well. Shortly after getting my Insight I installed a Rostra Cruise Control, which works very well.

However. I still wanted to have something that could be used to set the throttle position in "lean burn" and keep it there for longer periods than I could with just my foot.

The Rostra Cruise Control came with a special throttle shaft bracket (designed specifically for the Insight) that makes it simple to attach a second cable to the throttle assembly. I intended to clamp the second cable with a 12-volt solenoid, probably somewhat similar to what you have imagined. As I recall, when ordering the cruise control I had to specify an "Insight Kit" which came in a separate box and had the special pieces for the throttle. Perhaps you could order just the throttle pieces from a Rostra dealer. The "Insight Kit" did not include the cable and sheath assembly, it was attached directly to the cruise control unit. However, a short motorcycle brake or throttle cable should work just fine.

My second idea required having a cruise control to begin with. I built up a 555 Timer IC as an osscilator, designed to send a "fake" signal to the cruise control unit, making it think that it was maintaining a constant speed. This would allow the driver to set a throttle position in lean burn and then turn the cruise control on to hold the exact throttle position regardness of actual vehicle speed. The "fake" signal sent to the cruise control could be adjusted as necessary with a potentiometer.

In some respects I like the solenoid method better simply because it is simpler and doesn't require the expense of having a cruise control to begin with.

Let us know if you get something up and running.

[Mike Dabrowski 2000]

Lawson
The fake out of the cruise control with the 555 is a nice idea. I was thinking of getting a vacuume servo out of a junk yard's cruise control, and making a control circuit for it as an alternative to the solinoid. A throttle lock verses an adjustable throttle servo is the real decision to make.
If you want the best of both, I suggest you look at what Rick Reese did. He has a cruise control, and a mechanical idle adjuster. He sets the idle for maintaing the throttle at say 100MPG, and the cruise control for say 50MPH. come to a hill and the cruise control maintains the speed, over the hill, and the idle screw sets the throttle minimum. With PIMA, he can have the electric kick in just as the cruise ask for more power. The lower gas engine load should improve MPG, as the cruise control set speed is held with the electric priority PIMA as the primary power source. The PIMA also charges on the down hills automatically to maintain charge if he hasthe setpoints balanced correctly. Rick will be using his insight for the last few commutes to his old job, so we can have some good comparisons with the pre-MIMA data.

With your 555 VSS substitute, you may be able to autoswitch the real VSS with the fake VSS when the map signal shows increased engine load, and accomplish what Rick has with out the need for the mechanical device?
Worth a try. Be carefull interfacing with the MAP signal, as you will not want to alter it in any way as it determines fuel mixture and emissions.