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OBD0 8-Bit Rev Limit Formula

8-bit rev limit and engine speed restart formula for OBD0 VTEC Honda ECUs.

Beginner

Adapted from pgmfi.org wiki

For OBD0 Honda VTEC ECUs, the rev limit thresholds and recovery/restart speeds are calculated using the following 8-bit formula:

RPM = 1848000 / Decimal_Value

Where:

  • Decimal_Value is the base-10 value of the byte at the rev limit address.

Credits and source

Source Adapted from OBD08 Bit Rev on pgmfi.org wiki. Licensed under CC BY-NC-SA 1.0.