Products like the FAST Bump Stager allow drag racers to carefully pulse their vehicles’ transbrake (an internal brake in the transmission that uses hydraulic pressure to lock the driveline until it is released), allowing the car to move forward slowly during staging, creating a higher degree of repeatability than racers are able to achieve manually.
FAST does this through a patented function known as “transcreep.” It comes standard in the FAST XFI electronic fuel injection system, but the Bump Stager allows racers to use the function without the need to convert to that more expensive, all-out racing system.
It works with all vehicles equipped with an automatic transmission and an installed transbrake solenoid.
The racers that use the Bump Stager are predominately heads up drivers with turbocharged vehicles, although some bracket and class racers use it as well.
Turbocharged cars can take particular advantage of the system because they need to spool up the turbo to the point that they can leave the line with the adequate amount of boost.
“Turbo applications need to be able to start building boost while they are pre-staged (first bulbs on the tree activated) and wait there until the boost reaches the desired level, then, move the car forward into the staged position (second bulbs on the tree activated) while keeping it under load and the boost up,” explains FAST sales manager, David Page.
In the early days of turbo racing, racers would put two sets of brake calipers on the rear brakes and use them to try to hold the car in the first bulb while at wide open throttle until the boost reached the desired level.
Then, they would ease off the brakes just enough to move into the second bulb, which could be sketchy and might result in un-intentionally rolling through the second beam and red-lighting.
Finally, they would grab the transbrake, which is a much more steady way to hold the vehicle than the footbrake.
“With a Bump Stager using the transcreep function, the racer can ease into the first bulb, engage the transbrake, put the throttle to the floor, wait for the boost to reach the desired level, then activate the bump or transcreep function. This will allow the car to move a controlled distance at a controlled rate while holding the transbrake button down and staying at wide open throttle,” Page says.
“FAST patented the method of pulsing the transbrake solenoid to do this. Pulsing the solenoid at a high rate offers more smooth movement of the vehicle than other units.”
The complete kit comes with everything needed for use, and a built-in 20-amp driver that removes the hassle of wiring an external relay for most applications. The Bump Stager is fully adjustable with corrections for ramp in/out times and output frequency, plus it can control a shift light. Each kit features an LCD screen along with a high-quality anodized aluminum enclosure.