Q. Should I install the EGT probe before or after the turbocharger? I’ve heard before is best, but I saw an EGT mounting hole in an aftermarket exhaust system, and now I’m wondering if I can safely mount it after the turbo charger?
A. The ONLY correct position for the EGT probe is before the turbo in the exhaust manifold. There are two reasons for this: response time and accuracy. If the probe is mounted far away from the manifold, the lag between when the probe will register an increase in temperature, compared to the reading if the probe was placed in the manifold, can result in misleading EGT numbers. When used in conjunction with the Juice, this is of particular concern since the module needs to be able to de-fuel as quickly as possible to reduce EGTs when needed.
The second reason is accuracy. Putting the probe after the turbo can create inaccurate readings because the exhaust gas will cool as it travels farther away from the manifold. This discrepancy can be as much as 250 degrees, which is far too big a margin of error. Also, depending on the power upgrades you have made, the turbo itself may throw off the accuracy of a post-turbo reading. If the turbo is a restriction, excess heat will build before the turbo as hot exhaust gas backs up, while post-turbo EGT will be much lower – resulting from the reduced exhaust flow which cools even faster than it would in a balanced system. This situation can be particular dangerous because excess heat will quickly build in the motor while temperature readings after the turbo will seem almost too cool.
Remember, your exhaust pipe won’t overheat, but your engine will.
Q. What are EGTs?
A. EGT stands for exhaust gas temperature, and is the single most important indicator of how a diesel engine is performing. Unlike a gasoline motor, a diesel motor will continue to make power as more fuel is added. As more fuel is added, heat will be generated until the motor just gets too hot and things start to melt. This is a situation to avoid. Exhaust gas temperature is the ideal measurement of how hot the motor is, since temperature fluctuations in the gas are almost instantaneous. You should consider using the Edge Attitude or installing an EGT gauge even if you make no performance upgrades, since EGT is such an important indicator of engine load. This is particularly if you tow.
Q. I hear people talking about pressure boxes and timing boxes. What are they talking about?
A. There are basically three ways for a box to make more power in a diesel: timing, duration and pressure. Some boxes just do pressure, some do timing and duration and some do all three. If a box does just pressure, the box is fooling the truck’s computer into thinking it has less fuel pressure than it really does. In response, the computer increases the fuel rail pressure and so when the injectors fire, since there is increased fuel pressure, more fuel is released into the engine and additional power is created. This is the simplest type of power upgrade module and we have found it works very well for most Dodge applications and the Ford 7.3 Powerstrokes, as long as your power gains are limited to less than 70 horsepower. We have found raising fuel pressure on Ford 6.0 and the Duramax puts too much strain on the fuel system and so we do not make pressure boxes for these vehicles. Also, as mentioned, 70 horsepower is about the most you can safely gain in the Dodge and about 50 horsepower is what you can get out of the 7.3 Powerstroke.
As the name implies, a timing and duration box changes the timing of when the injectors fire, either advancing or retarding timing, as well as how long the injectors stay open when they fire. This takes considerable sophistication when it comes to understanding performance tuning as well as vehicle communication systems. We have found re-tuning through timing and duration works very well on the Duramax and the Ford 6.0. When done correctly, it can also produce big gains on most of the Cummins motors; however these gains will usually require additional aftermarket enhancements to the vehicle.
Q. What level should I tow in?
A. The only levels suitable for towing are levels 1 and 2. Only use level 2 if you are towing a light load. Never tow without an EGT gauge or an Attitude monitor. If you want to tow in a higher level, you must make significant engine and transmission upgrades beyond just a chip in order to handle the increase in power. It’s that simple. Even though the Attitude monitors EGT and will automatically de-fuel to prevent excessive EGTs, you should still only tow in level 1.
Q. Will my Juice work without an EGT probe hooked up?
A. The module will function normally, however, you will not have the safety feature of monitoring your EGTs and the Juice will not be able to backdown EGTs.
Q. It seems every product I see advertised claims 100+ horsepower gains, yet when I have driven a friend’s truck that has one of your competitors’ products, the performance just doesn’t seem that good. How come?
A. When it comes to horsepower claims there are many people in the industry state horsepower and torque gains using methods that while accurate, are not particular relevant to what the enthusiast is looking for in an upgrade.
The most common example of this is flywheel or crank horsepower claims vs. rear wheel numbers. If your crank shaft was connected to the road, this would be great a number to know. But in fact, your crank shaft is connected to other components, like your transmission for example, that act like a parasite and reduce power. What you really want to know is horsepower gains at the wheels. A typical truck uses about 30% of its power turning the gears, drive shaft and other components that sit between the flywheel and the tires. This means someone claiming a 50 horsepower gain at the flywheel is probably only making about a 35 horsepower gain at the wheels. Not bad, but not really as advertised.
The second popular method of “super sizing” horsepower claims is by quoting horsepower gain numbers based on some totally unusable part of the power band. Who cares if all your power gain comes after 3,000 RPM? When do you ever cruise on the highway at redline? (Certain Edge engineers, who are now strictly forbidden by our insurance company to drive company vehicles on public roads, being the exception). What you should be interested in is usable power gains in the low and mid range. This is particularly true if you tow. Before getting mesmerized by that 100hp claim, look at a before and after dyno graph and see if the gains are really where you drive.
Just so you know, at Edge, we only use rear-wheel horsepower numbers and we tune all our products to provide maximum performance in the most useable part of the power band.
Q. How do a obtain an Return Merchandise Authorization?
A. To obtain a return authorization, please call technical support at 1-888-360-EDGE between 9:00-5:00 MT. Be sure to have your part number, version number and manufacturing date (which is located on the silver sticker on the bottom of the unit) along with the complete explanation of this issue to expedite the process.