Ask Miles, our Setup AI that’s been trained on the RS4 Sport 3.
Setups
Gearing
Stock gearing for the HPI RS4 Sport 3, with common pinions and their ratios.
| Pinion | Spur ÷ pinion | FDR |
|---|---|---|
| 20T | 3.75 | 11.52 |
| 21T | 3.57 | 10.97 |
| 22T | 3.41 | 10.47 |
| 23T | 3.26 | 10.01 |
| 24T | 3.13 | 9.60 |
| 25T | 3.00 | 9.21 |
| 26T | 2.88 | 8.86 |
| 27T | 2.78 | 8.53 |
| 28T | 2.68 | 8.23 |
| 29T | 2.59 | 7.94 |
| 30T | 2.50 | 7.68 |
| 31T | 2.42 | 7.43 |
| 32T | 2.34 | 7.20 |
| 33T | 2.27 | 6.98 |
| 34T | 2.21 | 6.77 |
| 35T | 2.14 | 6.58 |
| 36T | 2.08 | 6.40 |
| 37T | 2.03 | 6.23 |
| 38T | 1.97 | 6.06 |
| 39T | 1.92 | 5.91 |
| 40T | 1.88 | 5.76 |
| 41T | 1.83 | 5.62 |
| 42T | 1.79 | 5.48 |
| 43T | 1.74 | 5.36 |
| 44T | 1.70 | 5.23 |
| 45T | 1.67 | 5.12 |
| 46T | 1.63 | 5.01 |
| 47T | 1.60 | 4.90 |
| 48T | 1.56 | 4.80 |
| 49T | 1.53 | 4.70 |
| 50T | 1.50 | 4.61 |
| 51T | 1.47 | 4.52 |
| 52T | 1.44 | 4.43 |
Shaded rows are the pinions most 1/10 4WD touring/gt setups run on the stock spur.
What pinion should I run?
Tell us your motor and track and get a starting pinion for the HPI RS4 Sport 3, with the range racers in the class run.
Get a recommendation →Shop pinion gears at AMain →What pinion gear should I use on the HPI RS4 Sport 3?
It depends on your motor and the track. In the 1/10 4WD touring/gt class, racers gear by final drive ratio: 6T and below near 7.34, 13.5T near 4.51, 17.5T near 4.51, 21.5T and up near 3.65. On the RS4 Sport 3's stock 75T spur that is about 31T for 6T and below, 51T for 13.5T, 51T for 17.5T, 63T for 21.5T and up. Tight tracks gear down, open tracks gear up. For a starting pinion matched to your motor, use the So Dialed Pinion Recommender with the RS4 Sport 3 selected.
What is the internal ratio (transmission ratio) of the HPI RS4 Sport 3?
The RS4 Sport 3 has an internal ratio of 3.071:1. Final drive ratio = spur ÷ pinion × 3.071. With the stock 75T spur, a 20T pinion gives an FDR of 11.52 and a 52T gives 4.43.
How many teeth is the stock spur gear on the HPI RS4 Sport 3?
75 teeth. Changing the spur moves every pinion's ratio at once; most racers leave the spur and tune with the pinion.
Kit setup
Kit shock setup. Part numbers link to AMain.
- Front
- 50 wt
- Rear
- 50 wt
What shock oil does the HPI RS4 Sport 3 come with?
Out of the box the RS4 Sport 3 runs 50 wt front, 50 wt rear, on 2-hole (#113694) front, 2-hole (#113694) rear pistons. That is the kit setup; you will need to adjust it for your track conditions. The RC Setup App can help dial it in.
What springs does the HPI RS4 Sport 3 come with?
The kit springs are Black (#6831) front, Black (#6831) rear. Stiffer springs suit high grip and big jumps; softer springs add grip on slick or bumpy tracks.
Setup Help
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