DBW Pedal Install

I opted for the DBW or Drive-by-wire throttle body on this build.  Mainly because that’s what was factory on the donor engine.  I used a Drive-by-cable (DBC) mechanical throttle body on my 1979 Malibu wagon swap so I thought I’d try this on this build.

I installed the factory OEM electronic pedal assembly from the donor truck directly onto a predetermined location on the firewall without making any modifications to the pedal assembly.  I carefully chose the location where the bracket mount would attach and marked and drilled three appropriate sized hole thru the firewall.  I attached the pedal to the firewall with 1/4″ carriage bolts from the engine bay into the cab.

Pedal mounted to firewall. Click to enlarge – use browser back button to return.

After the first drive, I found that with the accelerator pedal at the same height or level as the brake pedal there was a slight problem that I needed to address.  While driving, it was very dangerous to press the brake pedal because if not extremely careful, you would also touch the accelerator as the brakes were applied.  I needed to set the accelerator pedal farther back relative to the brake pedal as most vehicles are.

First accelerator pedal is too high. Click to enlarge – use browser back button to return.

I obtained another DBW accelerator pedal from the local scrap yard so as to not destroy the one I had already working in case it all went bad.  Pedal, TAC and wiring was only $5 !

After careful measuring of the physical travel as well as the electronic “travel” (throttle position movement) by using a crude jig,  I determined that I could adjust the pedal lower by approximately 2″ and keep 100% pedal travel.

Measuring pedal travel with jig. Click to enlarge – use browser back button to return.

I carefully cut a V notch in the foot pedal “arm”, bent it to the desired position and welded it in place.  After some tidying up of the weld and some satin black rattle can paint, it was like new again, only better.

Modifying accelerator pedal. Click to enlarge – use browser back button to return.
Modified pedal arm welded and ready for paint. Click to enlarge – use browser back button to return.
Modified pedal on bottom. Click to enlarge – use browser back button to return.

I reinstalled the pedal and the feel and location was much more like the original.

Modified pedal sits 2″ lower. Click to enlarge – use browser back button to return.