Using the Grid
In hard-core drag racing, controllability is king. Being able to program and monitor every aspect of your car and make changes accordingly is what separates the winners from the losers. One team who often wins with an MSD Power Grid is West Coast’s Eddie Rios, the tuner for Al Jimenez’s supercharged second-gen Camaro. Running as quick as 7.14 and as fast as 205 mph in the quarter-mile, this car actually holds the unofficial title of fastest car on leaf springs. We contacted Rios to pick his brain about how he uses the Power Grid to control one of the most powerful drag radial cars in the country.
Chevy High Performance: What prompted you to start using the Power Grid, and what did you run before?
Eddie Rios: We used the MSD 7531 box for years, which was great for getting the car down the track, but it lacked the ability of controlling the timing in a time-based retard. You could do time-based retard, but it had to be done through different nitrous retards. Now with the Grid you can make a whole graph and map out a retard table in time-based and in turn, control timing at any point in the run. On top of that, you can log what the Power Grid is doing through the RacePak data logger. We use the time-based retards, gear retard, shift retard, and the two-step rev limiter on Al [Jimenez’s] car.
CHP: How does the installation and display screen compare to the older Digital 7 box?
ER: Pretty much the same for installation, but the RacePak connection is a nice feature; it’s connected using one plug. The program [MSD View] is way more user-friendly and easier to navigate than the old one. I also noticed quicker upload and download times, and much more precision on the graphs also.
CHP: Do you use any of the Power Grid modules like the ARC module?
ER: I haven’t used the ARC module yet, since it only recently became available, but I do plan to use it because we use a time-based rev limiter in the 7531, which people refer to as “dots”. I read that it will also incorporate a driveshaft speed-based limiter also, which will come in very handy.
CHP: Do you think the Power Grid is a good upgrade for a radical street car?
ER: For some of the more powerful street cars, yes, but I really believe it’s a necessity in any heads-up drag race car. These days, if you’re trying to be on top in a class, you need to have a Power Grid and a RacePak, period.
Power grid Specs and Features
Four steps of rpm limits: for burnout, turbo spool, launch, and over-rev protection
- Output switch triggered by rpm, pressure, or time
- Timing based on engine rpm and gear value
- Advanced individual cylinder timing based on gear or time
- Five retard stages for nitrous
- USB connection for ease of programming
- Shift light settings for each gear
- Ignition data acquisition accepts multiple runs
Spark energy: 200-220 mJ per spark
Primary voltage: 545-570 V
Secondary voltage: 50,000 V
Spark series duration: 20-degree Crankshaft Rotation
RPM range: 15,000 rpm with 14.4 V
Voltage Required: 12-18 V, negative ground
Current Draw: 1.3 amps per 1,000 rpm
Weight and Size: 2.9 pounds, 71/2 inches long by 5 inches wide by 21/4 inches high
The CAN-bus technology allows you to expand the system using modules that can be easily added using a hub. MSD’s ARC module for example, allows you to set rpm limits based on slew rate (rpm acceleration) or based on time since launch. Designed to limit wheel speed, this add-on allows the tuner to finely tune their car’s launch characteristics, optimizing performance. In the event that engine and/or driveshaft rpm increase(s) at a pre-programmed rate, the module’s software will retard the ignition timing and/or rev limits in order to prevent excessive wheel speed. This data can easily be accessed and modified using the MSD View software on a laptop computer.