Power Electronics

The Spark’s power electronics mount to a lightweight steel sub-frame.

spark subframe
Figure 1. Spark power electronics sub-frame

The sub-frame has 4 mounting points and many grounding studs.

electronics on subframe
Figure 2. Power electronics mounted on sub-frame

Relatively few modifications were required to fit the sub-frame into the 240sx chassis.

  • The front arms were shortened to fit within the skinnier engine bay.

  • The rear arms, which sloped downwards, were cut off and replaced with square tubing.

  • Some material was removed to add clearance to the motor assembly.

  • Material was removed to add clearance for the steering column.

mounted subframe
Figure 3. Modified sub-frame mounted in 240sx
motor mount clearance
Figure 4. Motor mount clearance

To secure the rear mounting points of the sub-frame, M10 nuts were welded directly into the top of the frame rails. The front of the sub-frame fastens to M10 nuts which were welded to posts fabricated from round tube scrap.

The stacked sheet metal which makes up this part of the frame rails was once again painful to weld to. The expansion between sheets caused molten metal to burst out and melt through multiple layers of clothing.

steering clearance
Figure 5. Steering column clearance and front chassis mount

Once the sub-frame was fastened to the chassis, the power electronics were quick to install.

mounted subframe w electronics
Figure 6. Assembled sub-frame with electronics