On the left, we can see the cable-actuated 1991-1994 pedal. As the throttle pedal is pressed down (Green 1) it pulls on the throttle body cable (Green 2). Meanwhile, the cruise control cable (orange) pulls on the cable from the front hood area (Yellow 1). This causes the arm to rotate on a lower pivot (red arrow) and the throttle pedal drops down (Yellow 2). Just like when the normal throttle pedal is pressed, the throttle cable (Yellow 3) is pulled and the throttle body opens.
Comparatively, on the right is the 1995+ DBW throttle pedal. Notice how there is no lower pivot like the 91-94 pedal. As the throttle is pressed down (Green 1) the upper arm (orange arrow) rotates on the upper pivot (red arrow) pulling the throttle cable rearward (Green 2). This pulls on the throttle cable under the front hood that connects to the pedal position sensor which tells the ECU how far to open the throttle body electronically. Cruise control is handled electronically and unlike the 91-94 cars, the throttle pedal no longer moves physically to maintain speed.
Here we see the DBW throttle is now mounted in our NSX. What is special about this photo is the throttle pedal cover. This is the actual pedal cover that was used on the record-setting FXMD Time Attack NSX that I drove to many overall victories and records over the years.
We ordered a new OEM throttle cable from a 95+ NSX (17910-SL0-A03) to connect the DBW throttle pedal to the pedal position sensor.
The new throttle cable pulls on this OEM 95+ Accelerator Sensor (37970-PR7-A31) that measures the driver’s pedal position. The sensor has a return spring which dictates the pedal resistance and does a great job mimicking the pedal feel of the throttle-body actuated system in the 91-94 cars. The pedal position sensor connects to the mil-spec Zelaya Brother’s wiring harness that tells our Motec M150 what the pedal position is.
The pedal position signal travels across the chassis at the base of the firewall, under the (removed) HVAC assembly, and to the passenger side of the car.
4 comments
Another Billy cutting-edge NSX project! DBW opens up tons of interesting control possibilities!
The mid to late 90s in between/early years of DBW had so many weird contraptions. I would love to hear about why certain decisions were made for so many parts on cars!
i was thinking the same thing as he was going over the new DBW pedal.
Excited to see this paired with the ECU Master PMU16! Modern brushless fans and pumps are awesome, both in low power consumption and control capabilities. Let me know if you want another set of eyes on your turbo plans.