Trimatic Efficiency
From Holdenpaedia
Originally submitted by T:
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[edit] Trimatic Efficiency:
[edit] Power/Economy Switch Description:
If the vehicle is fitted with a Trimatic gearbox that has Electric Kickdown an improvement in efficiency (and therefore economy) can be achieved by fitting a Power/Economy switch.This Switch has an Indicator Bulb and is fitted between the Ignition Feed and the existing Trimatic Kickdown Switch.
The Switch allows the Trimatic to behave like most late model automatic gearboxes that have a Power/Economy switch fitted to them.
[edit] Advantages:
While Kickdown has the advantage of providing improved acceleration, it isn't always required.Leaving the car in the current gear and having the Engine pull against a load (something Holdens do best) provides better efficiency. Also Kickdowns jar the Clutch Packs, the Band and Gearset more than necessary. The gearbox will last longer running in the Economy setting.
[edit] Disadvantages:
The inconvenience of pressing the switch into the ON position when you want maximum acceleration.[edit] Practical Operation:
I've been running a Power/Economy Switch in the HZ and UC for over a decade and mostly leave the Switch in Economy.Very rarely do I activate the Power setting because hauling a stubborn load is what the EFI 3.3 and 202 thrive on.
[edit] Implementation:
[edit] Power/Economy Switch ON Position:
A suitable switch is available from Dick Smith Catalogue Number P-7723 (Red).
When the switch is in the ON position (Power), the Indicator glows and Kickdown is enabled.
The car now will change down gear when the Accelerator Pedal is floored under most circumstances (provided the Gear Lever is in Second or Drive).
Exceptions are when the car is at High Speed in Top Gear, or already running in First Gear with Drive selected.
[edit] Power/Economy Switch OFF Position:
When the switch is in the OFF position (Economy), the Indicator Light is out and Kickdown is disabled.
The car will remain in the current gear much longer but will automatically change down to a lower speed when the manifold-pressure/roadspeed figures are appropriate.
[edit] Operation:
[edit] Troubleshooting the Power/Economy Switch:
Remember that the power/economy switch only controls electric kickdowns at times that the shift valves in the gearbox allow kickdowns.
For example if the car is in second gear and travelling slowly,
say 25 kmh, a full depression of the accelerator with the switch
in the activated position will cause a kickdown to first.
The same is true if the car is travelling at a higher speed and in top. With the switch in the power setting (in other words allowing the
current to get through) then the gearbox will kickdown to second.
If the car is travelling too slowly in first the switch will have no
effect because the shift valves have no lower gear to kickdown to.
The same is true if the car is travelling at high speed (say above 100kmh) in top gear because the shift valves would not allow
a kickdown in that situation under normal conditions.
You can get an idea of how it should work if drive the same route
with the switch in the power position, then drive the route again
with the switch in the economy position.
If the switch is wired correctly, the car will remain in gear much
longer when the switch is in economy or may not even kick down at all
under circumstances where it previously did.
A test is to accelerate up a grade from a standing start with the
throttle wide open and the switch in "economy" (don't exceed the speed limit of course).
Wait until the car shifts up to second.
Once the car has shifted up to second keep the throttle wide open
and turn the switch to "power". The car should immediately kick back
down to first. After the kickdown to first turn the switch back
to "economy" and the gearbox should shift back up to second again.
This is going to depend on the steepness of the grade and how
much time elapses between you making the switch between "economy" and "power".
Note that if you have a very low diff the effect of the switch will
be less than if you use a taller diff because the gear shift points
occur at relatively low speeds with low ratio diffs. There are still gains to be made with low diffs of course, the gains just manifest themselves differently.
As far as the wiring goes ....
You should make sure that your kickdown switch works properly
before you add the power/economy switch. You may also need to reset the kickdown switch too.
You can test the kickdown switch the same way after you've wired it
if you've already done the work.
The kickdown switch is set when the car and engine are stopped and
the throttle is shut. Reach up and grab the small lever that sticks
out the side of the kickdown switch.
If you press the accelerator pedal you'll see that this lever is pushed by a linkage from the accelerator pedal. The switch should go click whenever the accelerator pedal reaches the hard on the floor
position.
To reset the switch release the accelerator pedal and push the
activation lever on the kickdown switch all the way forward. It takes
a little bit of force to make it break away. That force is normal.
Once this is done, push the accelerator pedal all the way to the floor. Now the kickdown switch has been reset. To check the switch
turn the ignition on but don't start the car. Whenever you floor the accelerator pedal you will hear the detent switch give a click inside the gearbox. You may need someone to push the accelerator pedal while you listen but it's an easily heard "click".
If the power/economy switch is correctly wired you will hear the
detent solenoid "click" when the switch is in "power"
and there will be no "click" when the switch is in "economy" no matter
where the accelerator pedal is or if the ignition is on or not.
If there's no click under any circumstances you may need a new
kickdown switch, or you have a failed detent solenoid or the wiring
is open or some other problem.
Wiring:
A WB has pink and orange wires connected to the kickdown switch.
The pink wire provides power to the switch only when the ignition
switch is turned on. You probably know that for early Holdens
the pink wire comes live when the ignition switch is turned to the
on position or when the engine is running.
The orange wire goes to the kickdown solenoid in the gear box.
When the kickdown switch is activated it connects the orange and pink wires together providing power to the solenoid.
As in the diagram, you should wire the power/economy switch before the kickdown switch so that the power/economy switch can get power
from the pink wire to drive its internal light.
Be aware that some switches you can buy are not faithful to their
diagrams. Dick Smith may have changed the internal connections of
that switch since I posted to Holdenpaedia.
If in doubt, use a separate switch and light rather than a switch with a light in it. Do this as a proof of concept if things don't come good for you straightaway.
You can use any old on/off switch that has no internal light provided it can handle 5 amps.
You need to remove the pink wire from the kickdown switch
and connect it to one side of the power/economy switch. Connect a new
wire between the the other side of the switch and the place where the
pink wire originally connected to the kickdown switch.
For the light, connect one end of the light to the new wire
on the power/economy switch and the other end of the bulb to chassis.
Leave the orange wire connected to the kickdown switch and untouched.
If you wire the power/economy switch onto the wrong side of the
kickdown switch the light will only receive power when the
kickdown switch is activated giving you incorrect info.
The light should come on when the power/economy switch is in
the "power" position saying the power is available for the detent switch.
When the power/economy switch is in the "economy" position the light
will be off saying that power is denied to the kickdown solenoid.
