The Ultra 6AL Plus builds on the Ultra 6AL with boost-dependent timing control up to 400 kPa (58 PSI / 4 Bar internal sensor), making it the ultimate ignition box for moderately boosted vehicles running a blow-through or draw-through carburetor. Programmable timing curves in 2D plots or 3D tables (RPM vs. timing vs. MAP pressure) can be edited from the "MSD Ultra 6AL" mobile app or MSDView software, alongside three rev limiters — Launch, Burnout, and Step Retard activation.
Specifications:
- Voltage Required: 12-15V (7V start)
- Maximum RPM: 15,000
- Spark Energy: 135-150mJ per spark
- Secondary Voltage: 45,000V
- Primary Voltage: 520-540V
- Current Draw: 0.8 amp per 1,000 RPM
- MAP Sensor: 4-Bar
- Weight/Size: 3.3" x 5.2", 498 grams
- Color: Red
- Warranty: Manufacturer's Limited 1-Year Warranty
- Part Number: 6523
Maximum programmable retard of 35 degrees; connects to points, magnetic pickups, and Hall/Crank input distributors on 4, 6, or 8-cylinder engines.
Compliance: This part is legal for sale and use on Racing Use Only Vehicles — competition vehicles that are not registered and never operated on the street. It is against the law to install this part on an Emissions Controlled Vehicle (1966-and-newer California-certified or 1968-and-newer federally certified vehicles).
FAQ
Is the MSD 6523 Ultra 6AL Plus legal for street use?
No. It's legal for sale and use on Racing Use Only Vehicles — competition vehicles that are not registered and never operated on the street.
What makes the Plus different from the standard Ultra 6AL?
Boost-dependent timing control up to 400 kPa (58 PSI / 4 Bar internal sensor), ideal for moderately boosted vehicles with a blow-through or draw-through carburetor.
How are timing curves programmed?
In 2D plots or 3D tables (RPM vs. timing vs. MAP pressure) via the MSD Ultra 6AL mobile app or MSDView software.
What rev limiters does it include?
Three: Launch, Burnout, and Step Retard activation.

