I will start this article by thanking Mike Steiger of Emjay Engineering LLC for providing me with a free evaluation unit and all the instructions and parts needed to perform the installation in our Truck test bed. Following is the "Foreward" Mike has
printed in the instruction booklet of the Strategy Controller
manual. You can get a strong indication of how and why the Strategy Controller came into being.
How the Strategy Controller came to life
Copyright © 2002 Emjay Engineering LLC. All Rights Reserved.
The Emjay Engineering LLC, STRATEGY transmission controller combines
OEM quality electronics with aftermarket features that enhance the capabilities of the
Dodge Cummins RAM pickups in an area that has been sorely lacking all along: the 47RE
automatic transmission. It is well known that the weakest link in the Dodge RAM Cummins
pickup platform is this transmission. That’s why there is an entire segment of the
automotive aftermarket devoted to it. Even Dodge dealers are installing after market transmissions in
the Cummins equipped trucks. Ask anyone who has modified their truck for power, and they’ll tell you that adding
evenentry level engine performance products expose the shortfalls of the 47RE
transmission. This is due to the fact that the Cummins engine is detuned to the hairy edge of
the transmission’s capability. While you may not agree with that, consider that minor
torque converter slippage is difficult to detect unless you know what to look (or listen) for.
Even minor slippage over time can contribute to reduced transmission service life.
Most will agree that the torque converter is the weakest component in the
transmission. There are many aftermarket torque converters available, and any one of them is a
huge improvement over the stock converter. I will not get into preferences because there is
an almost religious following of certain torque converter and transmission
manufacturers.
The Chrysler 47RE automatic transmission is defined as an
electronically controlled transmission, but only certain functions are electronically controlled. The 47RE still
shifts hydraulically, but the torque converter clutch and the overdrive are controlled by
solenoids. The governor pressure that used to be controlled by centrifugal force by means of
special valve(s) on the transmission output shaft, is controlled electronically by the PCM on
the 47RE. This was deemed necessary because the mechanical governor’s linear
response provides sub-optimal shift curves to meet government standards, presumably
CAFÉ (Combined Average Fuel Economy).
This is an important point because the system is not optimized for engine longevity or performance, it is optimized to attain some
statistical number to meet a standard. Presumably, the electronic governor was added to the
47RH transmission to meet that goal, and the 47RE was born.
The PCM varies the governor pressure slightly from an otherwise linear relationship to
the output shaft speed. This pressure is tightly controlled in a closed loop comprised of
the governor pressure sensor and the variable-force governor solenoid.
Emjay Engineering LLC modifies the response of this closed loop system without “breaking” the closed loop.
Emjay Engineering LLC has a patent pending on this method.
So what does that all mean? The bottom line is that governor pressure curves are made adjustable, and therefore the
shift points are adjustable. This is the first product of its kind with this
capability. There are numerous diagnostic functions built into today’s cars and trucks, and
modifying the response of a component or system without detection by these diagnostic
functions require ingenuity and finesse. That is not necessarily because the modified system
is operating in a dangerous or unreliable manner, it is because each diagnostic function has
a fixed set of rules for a given component or signal.
Used by permission
Author: Mike Steiger Emjay Engineering LLC
| Will the Strategy Controller help a stock truck? or will it only work on a modest to heavily modified truck?
Would a Strategy controller be of any help to someone who wants to get a little better control over his existing transmission, but just can't afford any upgrades right now?
We will attempt to answer these questions and more in this
series of articles.
How does the average man go about adding expensive modifications to his truck?
Being able to drop $6,000.00 dollars or more at one time on your family truck, is not something most guys are able to do. We took this into consideration and decided the best way to evaluate the Strategy Controller was to put it alongside some of the more common modifications being done today, and see what these combinations have to offer. In this manner we hope to be able to show the reader what he can expect in performance improvements as he builds his dream truck one step at a time. We chose for our test bed a 1996 Ram 2500 4x4 with approximately 100,000 miles on it. This truck having been well maintained runs strong but was beginning to show the slightest signs that the transmission might need a little attention. Shift points were not as strong as they had been, and the torque converter seemed to take a little longer to achieve lock up. All of these symptoms are quite common for a truck with this kind of mileage on it. The owner had installed a set of gauges on an A pillar pod to monitor EGT temperature, Boost and transmission temperature, but beyond that the truck remains stock. Drawing up a game plan The first order of business was to sit down and decide what kind of modifications would be needed for the future this vehicle would be
facing. The owner intends to use it primarily for towing a camper and the occasional load of gravel or firewood.
He wants it to remain calm enough so his wife won't feel intimidated by driving it around town and at the same time, strong enough to pull even the steepest grades with ease.
Keeping this in mind we decided on several options that should turn this nice truck into a great workhorse that should be very capable of leaving quite a few people wondering if they left their parking brake on. Transmission upgrade
The first part of our testing the new Strategy Controller, will be installing it in the stock truck to see if the Strategy controller on
its own seems to affect the overall performance of the stock transmission.
At no time has the manufacturer Emjay Engineering, made claim that the Strategy can help fix the common symptoms that this transmission is displaying.
Yet still from a purely scientific point of view we are curious to see if it can help moderate the signal coming from the aging TPS.
These simple units are notorious for their noisy signals they produce, and the Strategy Controller can by design take this signal, buffer it run it through a low pass filter and then re buffer it!
Will this help an aging TPS perform it's duties better? Maybe, but even still a bad TPS should be replaced.
Still I am curious what the outcome will be.
To Be Continued...
This is the first installment in an ongoing technical article intended to shed some light on some new and exciting products that will hopefully take care of some old problems.
Please keep an eye out for the next installment to be added very soon!.
This ongoing article is written by Staff Writer: Lary Ellis
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