The "R" or Racing model of the 432 is lighter weight, and it could be ordered with several combinations of transmission ratios and rearend ratios. The "lightened" version was built on the base Fairlady Z (Model S30S) which lacked some of the carpeting and sound proofing found on the Fairlady Z-L" or Luxury model (Model S30). Additionally the R model was equipped with a fiberglass front apron and hood, plexiglass side and rear windows, light weight bucket seats with the drivers side equipped with four point harness. There was no Clock nor heater in the R Model - however it did get the fiberglass rear spoiler. A fiberglass cover was used under the engine and transmission, while heaver gauge sheetmetal was used in high stress areas of the unit-body (suspension mounting points). Lighter gauge sheetmetal was used in other areas of the body for additional weight savings.[/size]The R Model left the factory with the 4.5 inch steel wheels - as it was assumed that the racing teams would want to select and use their own wheel / tire combinations. The expensive Mag. wheels were standard on the 432 (not the 432 R )