Rear Suspension Bushings

Structural inspector required that the rear lower suspension bushings needed to have shoulders. Ordered bushing kits and had to turn them down on the lathe. Ordered new suspension bolts to accommodate the additional length required by the bushing shoulders.

Wheels

Chamged the rims and tires to another set off a Miata. They are 14s. We checked the outside of the rim with a dail indicator to determine if or how bent they and the old rims were. Generally the new rims had 5-12 thousands variance. The old rims had around 40-45 thousandths variance.  Rubber also appears to be in better condition.

Suspension arm and alignment

Brought in the suspension arms and uprights towards the chassis as much as possible while keeping the movement even at all points (upper a arm rod end, lower control arm mounts, and steering rack toe adjustment). Generally brought everything in on both sides by 19mm which provides much more bite between the upper a arm and rod end mounting into the upright.

Will have to perform alignment next time.

Steering rack angle modification

Took a look at the Haynes and Saturn sports car guides and saw that both use the ford steering rack which has the steering shaft angled below horizontal when the rack is mounted flat. The Mazda rack steering shaft is angled above horizontal when mounted flat. When building we failed to realize this and ended up with a steep bend in the rack U-joint. We’ve rotated the rack slightly to reduce the bend in the U-joint to about 30 deg.  This should help reduce uneven steering.

Structural Inspection

Received car back from Victoria Frame, the structural inspector with the following list of repair items and recommendations. Will need to work though the requirements and reinspect.

Requirements (Frame, Suspension):

  1. Right outer tie rod has moderate play and needs replacing.
    1. ACTION: Replace with new.
  2. Left front upper control arm rearmost pivot nut/bolt is loose.
    1. ACTION: Install shims and tighten nut.
  3. Rear shock upper mounts are too wide & need shims.
    1. ACTION: Install shims to reduce gaps.
  4. Left & Right rear upper control arm mounts need to be shimmed/tight.
    1. ACTION: Install shims to reduce gaps.
  5. Left rear lower control arm rearmost mount is missing a weld at the frame (all other ok).
    1. ACTION: Install missing weld.
  6. Front upper tie rod end/control arm joint at hub are extended too far out and need:
    1. ACTION: Option #1: fabricate larger upper control arm to allow tie rod end to thread in to sleeve fully.
    2. ACTION: Option #2: Reduce front track width to bring tie rod end into sleeve as much as possible
  7. Pop rivets on the left side floor to frame may not be fully engaged
    1. ACTION: Replace rivets.

Recommendations:

  1. Front wheel bearings and/or brakes are noisy.
    1. ACTION: Re-check after some KMs put on car.
  2. Rear wheel bearings are noisy.
    1. ACTION: Re-check after some KMs put on car.
  3. Steering coupler shaft feels like the u-joints are binding – possibly at too much of an angle.
    1. ACTION: Reduce u-joint angle by installing second u-joint or rotating steering rack.
  4. Tires are lumpy and shifty.
    1. ACTION: Buy new tires.
  5. All rims are bent
    1. ACTION: Buy new rims.
  6. Wheel weights look ready to fall off.
    1. ACTION: see above.
  7. Bare welds under rear sheet metal.  Recommend coating.
    1. ACTION: Install coating on weld (paint).
  8. End caps could be made to block off open ends of frame rails at rear.
    1. ACTION: fabricate caps (rubber? silicone?)
  9. Minor fluid leaks

Front and rear bumpers PT 2

Finished off the front bumper this weekend.

Painted rear bumper.
Rear bumper chassis mount.
Rear bumper.
Upper front bumper chassis mount.
Lower front bumper chassis mounts.
Holding front bumper mounts together for tac welding in situ
Front bumper.
Welding front bumper.
Painted front bumper.
Painted front bumper.
Completed front bumper.

Build diary of Jeffrey Sevold's supercharged mazda powered Lotus 7.