Ford – Speed Density ECMs


The first EFI ECMs used by Ford were speed-density featuring a MAP sensor and either a manual or hydraulically shifted automatic (C4/C6/AOD/etc) transmission along with electronically controlled ignition advance with a distributor.  They’re commonly found on early fuel injected Ford trucks like F150, 250, 350, Broncos and even early speed-density 5L mustangs/crown vics/etc.

Later models added AOD-E and E4OD electronically shifted transmissions.

The first generation Lightning trucks came with a speed-density 351 and a E4OD transmission.

These ECMs batch-fire injectors.  Swapping to later ECMs typically provides a slight improvement in fuel economy when the replacement ECM uses sequential injection.

As a rule of thumb, software support is very limited for these models compared to MAF vehicles like Fox Body A9L platform.  These may not be the best choice for a beginner or someone without prior tuning experience.  Be warned.

Strategy/BIN Swapping

While support in general is very limited for these models, there are a select few models/applications that are well-supported.  Fortunately, it is sometime possible to “swap strategies” and use a bin file that has software support in an ECM which otherwise lacks direct support.  Unlike MAF ECMs, the specific combinations of engine components factor highly in each particular speed-density calibration.  Use of a well-supported bin/strategy with a different engine than it was originally intended will often require major tuning due to differences in cylinder count, engine displacement, compression, camshaft.

The easiest way you can figure out which strategies will interchange is to match the hardware ID on the label of the ECM.



This is an “EFI-SD48B” ECM.  Any bin/strategy that runs on it (including a first generation lightning C3P1 / LHBL0 / LHBL1 ) will also run on other EFI-SD48B ECMs, and probably EFI-SD48E etc.  I don’t have an exact guide for swapping but if it is very close it’s at least worth a shot.

This document will be published incomplete and added to as I find more information and details.

Supported Hardware-Software Combos

These are known working combinations.  Each of these corresponds with a specific hardware ID or IDs known to interchange.

EFI-SD4x family: speed density, E4OD transmission.  Native to Bronco, Lightning, F150, F250, F350 approximately 1992-1995

  • Box codes C3P1, C3P2, C3p3 (1st gen Lighning), ICY1, T2X1, many more
  • Hardware IDs EFI-SD48B EFI-SD48E and more
  • LHBL0 / LHBL1 strategies will run on the hardware, maybe more
  • Supported by Core Tuning definitions ( ) LHBL1 strategy
  • Supported by Binary Editor (maybe?) via LHBL1.xlsx definition (BE website)
  • Supported by Decipha’s speed-density definitions for TunerPro RT ( EFI-SD4X [A1C] )
  • Decipha suggests that his definitions for TunerPro RT will work for “EFI-SD4x” implying that broad strategy/bin swapping is possible.


EFI-SD2X family: speed density, C4/C6/AOD non-electronic transmission.  Native to F150, Bronco approximately 1985-1993

  • Box codes 8PZ and more
  • Hardware IDs EF-SD20B and more
  • Supported by Decipha’s speed-densite definitions for TunerPro RT ( EFI-SD2X [C9C1] )


SFI-SD1 family: 87-88 Mustang 5.0 speed density


Z2D1 / EFI-SD47B / F2TF-12A650-AHB: Supported by EEC Editor def/dlm edit/log via Z2D1 specific.  May also work with other options.


Unsupported/Unknown Hardware-Software Combos

SFI-SD3 / EA2 1988 Lincoln town car