Programming the Advance Curve
To appreciate the real genius of the Max-Fire, you must first have some
basic knowledge of how to determine an appropriate advance curve for your application. Alternatively, if you already have a good performing curve for your motor in mind, based on your current mechanical advance curve, you can simply apply it to the Max-Fire as a starting point. Once your current curve has been programmed in and you realize how easy it was to do, you'll be tempted to tweak that curve or experiment with different curves altogether.

For those of you who have no real experience curving a distributor, there are some general guidelines for creating an advance curve that use your cam's duration and cylinder head's burn quality as an indicator (See sidebar "General guidelines for selecting an advance curve"). We hesitate to say these guidelines should be treated as gospel, but they will get the newbie started and encouraged to program and experiment with the Max-Fire. We can confidently say that the speed and control with which one can "re-curve" the Max-Fire will have even the most inhibited enthusiast researching and chasing down the perfect advance curve.

Most notable about the Max-Fire is that it can be programmed inside the house behind a desktop computer. As mentioned, the 9 volt harness allows it to be powered up on its own.		The included Max-Fire Electronic Distributor Software is Windows based and runs on almost any PC.
The Max-Fire includes a serial cable to communicate between the distributor and your PC.		The 9 volt harness is a throw back but it does the job of powering the distributor when it has been removed from the motor.
Yes, that's the distributor on the desktop along with the software interface on screen.		Alternatively, if you have a laptop, the Max-Fire can be left in the motor, powered by your battery, and connected using the same serial cable.

Using the Mallory Electronic Advance Software
The magic behind the Mallory Max-Fire and what separates it from the pack is the simple software interface and ability to create curves and get instant feedback in the form of a graph. To test out the product, we pulled the MSD billet distributor and 6AL out of our 460 powered 1973 Torino, dropped in the Max-Fire, and static timed it with 14 degrees of initial advance. Once we had it wired up and connected to the coil (Mallory ProMaster E-Coil), we attached the serial cable to the distributor and connected it to our laptop, which was already loaded with the Mallory software.

Simply clicking the "Read Data" button displayed the Max-Fire's default
advance curve values (Curve 1) and resulting graph. This default curve was a bit quick for our street application, bringing in total advance by 2500 RPM. Regardless, let's take a look at Curve 1 to understand the programmable values and interface.

Preprogrammed Curve 1
There are a few things to note upon viewing Curve 1. You'll first notice that this preprogrammed curve only uses Segment 1 to run all 22 degrees of advance and that the "curve" is perfectly linear. This might be a good curve if you were constantly mashing on the gas or at the drag strip, but it's not optimum for the street. Obviously, the 22 degrees of advance does not include your initial advance. The values controlled through the form fields designated "Seg" should be treated just as if you were adjusting the mechanical advance on a standard distributor. Values for "Seg 2 End RPM" and "Seg 3 End RPM" are irrelevant in this scenario since the "RPM Limit" is set to 6500 RPM. Curve 1, the remaining six preprogrammed curves, and the "Custom" mode all include the same vacuum advance settings as indicated in the this screen shot. However, "Vac Adv", "Boost Retard", and "RPM limit" can all be adjusted independently from the preprogrammed curve settings.

Custom Curve to Match Prior Mechanical Advance Distributor
As a first step into programming our own curve, we simply set up the Max-Fire to match the mechanical advance of the MSD distributor we just replaced. The MSD curve had been tuned a few months back and proved to be a good tune with 14 degrees initial and 20 degrees of mechanical advance, all in by 3000 RPM. The screen below mimics the mechanical curve precisely. We fired up the 460 and found the Max-Fire's ignition performance indiscernible between the MSD and 6AL.

Custom Curve with Two-Stage Advance
You may have noticed that the two screens we've shown so far do not take advantage of the Max-Fire's ability to run a staged advance curve. Two stage advance curves are preferred for street driven V8's because the quicker advance at low RPM provides good throttle response while the slower advance at mid RPM helps prevent detonation. Unless you've used a specialized two-stage mechanical advance spring kit, most likely you're running a perfectly linear advance curve. Linear curves are more
appropriate for race motors where full advance is desirable at the lowest RPM that the motor will see wide-open-throttle, this can be as low as 2000 RPM. Based on that information, we modified the curve using the custom curve feature. See the drop down menu next to "Select Curve". Keep in mind, the rough attributes of the curve are the same as before with 14 degrees of initial advance and 20 degrees of "mechanical" advance, all in by 3000 RPM. However, the staged curve dictates two events, a steep ramp just off idle to 1700 RPM and a more gentle ramp from 1700 RPM to 3000 RPM. This curve did result in improved low RPM throttle response.




Special Applications
If you are a forced induction guy, you probably noticed that the screenshots above have an input for "boost retard." The Max-Fire distributor has a built in 3 BAR MAP sensor which detects maniflold pressure and therefore can be used to back-off timing under boost per your specification. Simply connect the vacuum port on the exterior of the distributor to a manifold vacuum source. As you likely know, this is a huge plus since it eliminates the need for an external boost-retard box and associated wiring.

Final Thought on Advance Curves
The optimum advance curve for any particular application depends on many variables. Usually, a mixture of past experience and trial and error are required to determine the best curve. Dyno sessions and track test time will aid a race minded-enthusiast in determining the best performance curve. However, the best advance curve for drivability can be as unique as your own driving style. The Mallory Max-Fire distributor we demonstrated here only makes it easier and faster for the enthusiast to find "their" curve.