Tamiya TRF 417X Project

The fourth generation of the TRF touring car line began in December of 2010 with the 42184 TRF 417 chassis one year after the last version of the previous generation (TRF 416X) at exactly the same price point.  Compared to the TRF 416X, the primary differences are related to being setup for more modern electronics including rectangular hard pack batteries and brushless motors.  The first update came out the following June and was designated 42200 with the only change being the addition of a rear gear differential in place of a ball differential making it really just a standard TRF 417 with optional parts included.  The following December (one year from the initial model) Tamiya released the 42205 TRF 417X which incorporated the same gear differential and minimal other changes and simplifications. In July of 2012 Tamiya released a special edition, the 42235 TRF 417X Reedy Race Victory Commemoration set.  This version was based on the changes driver Viktor Wilck  made to win the 2012 Reedy International Touring Car Race of Champions.  Information on this version is very sparse (I was never able to find a manual).  It came in a standard TRF 417X box with an extra sticker on the cover and only cost an additional ¥10,000.  Anecdotal data suggests that the only changes may have been a different sticker sheet and an optional front gear differential in which case it probably had no unique manual.  This limited edition set had apparently only 200 copies produced.  Finally, in December of 2012 (2 years from the initial model) Tamiya released the final version which was designated the 42240 TRF 417 V5 (the fifth generation of the chassis, if you count the special editions).  Despite a considerable list of changes, it was offered at the same price point as the TRF 417 and 417X.  This version was based on what driver Jilles Groskamp used to win the IFMAR ISTC¹ world championship earlier in 2012.  I present a detailed list of the changes to each major generation of the model in the table below. 

¹ International Federation of Model Automobile Racing, International Scale Touring Car class

TRF 417X	TRF 417 V5
Oil filled gear differential instead of ball differential 3-piece center bulkhead replaces 1-piece Stronger (metal) battery holders Steering brace removed Softer upper and lower chassis decks More damper position options on shock towers	Far fewer cutouts in lower chassis deck Additional pockets in bulkheads Stronger differential drive cups 2-piece motor mount replaces 3-piece Rear suspension mounts use 1XB and 1D instead of 1XA and 1E Front suspension uses new 1B split mounts instead of solid 1C New front double cardan CVD axles New aeration dampers New one-sided servo mount No wheels included Much less secure battery support

Unlike many prior TRF chassis, I couldn't find any evidence of upgrade kits allowing conversion of one chassis version to another, or of alternate aluminum chassis plates.  Of course, the gear differential was available separately which effectively allowed conversion from a 42184 to a 42200.

The TRF 417 is extremely similar to the TRF 416. Like all the TRF touring car chassis, this a twin belt driven 4WD model with carbon fiber chassis plates, loads of machined aluminum parts, and generally the best parts Tamiya could come up with including hardware and axles.  The general layout with the electronics on one side and the battery on the other is the same.  The real changes are all in the details and are explained much further in my build journal below.