Logic overdrive devices.
I have read with some amusement all the too-ings and fro-ings
on this subject with some correspondents making it all sound desperately
difficult.
What is the background? Well, when Revington TR was called TR
Spares Southwest in 1982 ish, I designed a device to allow me to change gear and
overdrive at the same time specifically with racing in mind but obviously I
found that the device was a fantastic improvement on all cars both road and
competition. I called this device a ’Logic Overdrive device’ (sound
familiar?)
Initially the device was constructed of basic electrics but
has since been redesigned and is now fully electronic.
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| RTR1001K |
 |
| RTR1296NK |
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| RTR8436 |
So how does it operate and how do you fit it? There is no
need to remove the gearbox tunnel, the box of tricks and all the other fittings
that come in the kit (which comes with full instructions), is wired into the
existing wiring from the gearbox tunnel upwards to the switch and original relay
(pre CF CR TR6 cars). A flick switch
RTR8436 is used to operate the system and in the
case of TR4-6 the original switch can be modified to become a flick switch
(Meaning momentary operation with self-return). The modus operandi is this:
Whatever gear or state of overdrive the car is in when the ignition is turned
off, the overdrive will be off when you turn on the ignition again. When
overdrive is required (in an overdrive enabled gear of course), flick the
switch. When a non-overdrive gear is required from an overdrive gear, flick the
switch. If a fast change is required from say 2
nd overdrive to non
-overdrive 3
rd , just move the gear lever to 3
rd and the
logic device will disengage overdrive for you as you pass through the gear shift
gate. This applies to any gear change up or down the gearbox where the start
point was an overdrive gear.
We recommend a light on the dash to identify the overdrive
state. And it is worth noting that both negative and positive earth devices are
available.
Two types of kits are available
RTR1001K which is a basic
unit suitable for both positive and negative earth and
RTR1296NK, RTR1296PK
which provide a facility to dim the indicator lamp independently for both day
and night. The ‘N’ and the ‘P’ in these part numbers indicates negative and
positive earth variants.
To find out prices and more, just click on the part numbers above or type these part numbers into the
search box on our website
www.revingtontr.com
That is the history and I can confirm these units have been
sold by their thousands and continue to work faultlessly in many applications
(not just TR’s) around the world, so now there is no need to go searching for
components to build a device that may or may not work, it has all be designed
for you and been field tested in thousands of cars for the last 30
years.
J. Neil Revington
