After a full year of my son and I racing our 2wd Slashes in the “Spec Slash” class, I wanted to record everything we’ve broken, fixed, upgraded, and replaced. I’ll also include a setup sheet of what we landed on being a fairly consistent indoor off-road carpet track setup.
Spec Slash rules differ by track, so check with your local track(s) before you buy anything. Some allow replacing stock plastic parts with RPM brand replacements, some do not. If you race at multiple tracks, better to error on the side of caution and stick with stock parts. I’ve included both parts here for reference.
To slow the Slash down to believable crawler speed I actually kept the stock gearing in place (19.23 Final Drive Ratio for the brushed 4×4). Then I added a RC4WD 1:3 Gear Reducer, which would change the final drive ratio to almost 60:1 – a popular ratio amongst crawlers and close to the TRX-4 low-speed setting.
The gear reducer is normally a bolt on part, but there were some tweaks I had to do to get it to fit the Titan 550 motor. First the receiver hole in the gear reducer is too small fo the 550’s standard 13mm bearing enclosure (the part that sticks out right before the motor shaft). Which is strange because the age-old Tamiya 540 motor also specifies 13mm for this part of the motor.
The arms are going to be the single biggest difference maker when it comes to overall width. As part of my research I gathered a list of several Slash-compatible arms and their lengths. If you’ve got more arm lengths to add to that list, please comment below.
Bandit arms are 67mm wide, while the stock Slash 4×4 arms are 92mm. Just by making this switch we’re going to remove 50mm of overall width, bringing it from 296mm wide to potentially 246mm – less than the goal of 249mm. So we have some width we can add if need be.
Here you can see two sets of Bandit arms compared to the original Brushed 4×4 Slash arms: