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Old 09-19-2014, 04:57 AM
  #22  
BloodClod
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Let's stay focused on the SB401 shall we?

PART TWO...

Next up the front and rear diffs are installed into the differential cases. The inner bearing for the input pinion shaft is larger and should last a long time. PR Racing also provides shims to shim the differential inside the gearbox. Use sufficient shims to prevent any side to side play of the differential in the gearbox and add shims to the ring gear (the large gear) side if there is too much play between the ring and pinion... just a bit of play for smooth rotation will be sufficient.


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Here's the front gearbox installed on the chassis. The front of the gearbox is removable so by taking out 6 screws you will be able to access the differential for servicing and oil changes! Also check out that beefy 4mm carbon fiber shock tower.


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The universal driveshafts are installed next. The front driveshafts use a C-clip to secure the universal pins whereas the rear pins are captured in the oversized hub bearings. The shafts are beefy and went together very well with no slop and no binding.


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The front arm and steering assembly are assembled next. Arms are beefy and include droop screw holes but unfortunately the chassis has no supports for the droop screws so droop can't be set that way (perhaps a future upgrade?). Hingepins are solid 3mm and captured by tiny screws on the outer part of the arm.

Height of the steering spindle can be adjusted with included collars and the wheelbase can also be adjusted with the spacers on the inner hingepins. I found the spacers just a tad too thick and a few rounds on 600grit sandpaper made it fit just right.


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The car comes with a full set of 4 aluminum hingepin blocks (front and rear) anodized black. These are well made and should not have any durability issues.


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The arms are installed on the chassis and front kick-up is adjustable with the included shim. A tiny bumper doesn't protect much more than just the front hingepin block. I'm not a fan of these tiny bumpers but they seem to be the trend these days.


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Entire front assembly mounted. The car comes with 14mm aluminum hexes that are attached to the axle via a 3mm setscrew. The front are nicely machined for some weight savings too. Also included in the kit are a set of 12mm plastic hexes should you prefer to run 12mm wheels.

For the record, Durango front wheels fit perfectly on the car but unfortunately Durango rear wheels do not fit on the rear axles as the axles are too short and hence do not extend far out enough to install the locknut.

The car features burly steel turnbuckles all around. Build tip - GREASE the turnbuckles before threading into the rodends! The rodends themselves seem to be very durable and to be honest are extremely hard to "pop" onto the balls - PRO = they are unlikely to pop off when you are racing that important run, CON = if they do pop off, it's unlikely they are going to be easy to pop back on again...


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The rear gearbox ready to be installed. PR has cleverly designed the front and rear to use the same gearbox casings so you can save on the spares you have to keep. Rear shock tower is 4mm thick. It features only 2 holes for shock tuning and that does seem less than most other cars... but hey, if the geometry is right perhaps I don't need more than 2!


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Another shot of the rear gearbox showing the beefy wingmounts. The wing will be held on with screws (no wimpy snap pins here lol!). Like the front, the differential can be accessed by simply removing 6 screws from the gearbox.


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Will update this post as the build progresses.
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