Ask Miles, our Setup AI that’s been trained on the T4F '19.
Car Not Handling Right?
Diagnose understeer, oversteer, traction rolling and more — by symptom.
Setups
Gearing
Stock gearing for the XRAY T4F '19, with common pinions and their ratios.
| Pinion | Spur ÷ pinion | FDR |
|---|---|---|
| 36T | 2.67 | 6.33 |
| 37T | 2.59 | 6.16 |
| 38T | 2.53 | 6.00 |
| 39T | 2.46 | 5.85 |
| 40T | 2.40 | 5.70 |
| 41T | 2.34 | 5.56 |
| 42T | 2.29 | 5.43 |
| 43T | 2.23 | 5.30 |
| 44T | 2.18 | 5.18 |
| 45T | 2.13 | 5.07 |
| 46T | 2.09 | 4.96 |
| 47T | 2.04 | 4.85 |
Shaded rows are the pinions most 1/10 FWD 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 XRAY T4F '19, with the range racers in the class run.
Get a recommendation →Shop pinion gears at AMain →What pinion gear should I use on the XRAY T4F '19?
It depends on your motor and the track. In the 1/10 FWD touring/gt class, racers gear by final drive ratio: 17.5T near 4.51. On the T4F '19's stock 96T spur that is about 51T for 17.5T. Tight tracks gear down, open tracks gear up. For a starting pinion matched to your motor, use the So Dialed Pinion Recommender with the T4F '19 selected.
What is the internal ratio (transmission ratio) of the XRAY T4F '19?
The T4F '19 has an internal ratio of 2.375:1. Final drive ratio = spur ÷ pinion × 2.375. With the stock 96T spur, a 36T pinion gives an FDR of 6.33 and a 47T gives 4.85.
How many teeth is the stock spur gear on the XRAY T4F '19?
96 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 (Medium grip). Part numbers link to AMain.
- Front
- 450 cst
- Rear
- 450 cst
- Front
- 300,000 cst
What shock oil does the XRAY T4F '19 come with?
Out of the box the T4F '19 runs 450 cst front, 450 cst rear (XRAY oil), on 4 x 1.1mm (#308037) front, 4 x 1.1mm (#308037) 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 XRAY T4F '19 come with?
The kit springs are 2.6 (#308286) front, 2.5 (#308275) rear. Stiffer springs suit high grip and big jumps; softer springs add grip on slick or bumpy tracks.
What diff fluid does the XRAY T4F '19 come with?
The kit diff fluid is 300,000 cst front. Thicker front adds steering on power; thicker center sends more drive rearward; thicker rear stabilizes the car under throttle.
Setup Help
All Touring Cars →
Free to start · iOS & Android
Setup App & Race Log
Your XRAY T4F '19 is in the RC Setup App
Save every setup change you make to your XRAY T4F '19, get AI tuning answers for that exact car, and log your races — at the track or back in the pits.
- Setup Tracking
- AI Mechanic answers
- Find & Share Setups
- Race Log
- Gear Ratio Calculator
- Free to use
