2-Step Rev Control
• For Digital 6AL only (121-6425)
  
  MSD's 2-Step Rev Control allows racers to switch to a low rpm limit at the starting line. This digitally-controlled 2-Step Controller connects to the Digital 6AL's gray tach output wire and has (2) rotary dials that let you set the launch rpm in 100 rpm increments. An activation wire connects to the transbrake, a clutch switch or to the line-lock to activate the low rpm limit. When releasing the switch, the low rpm limit is turned off and the car launches hard.
  Features:
• The rpm limit is set with the (2) rotary dials, in 100 rpm increments
• For Digital 6AL only (121-6425)
• For use with Digital 6AL PN 6425 or 64253 only

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

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