JAC · JS8 Pro · kPa
231 kPa front, 231 kPa rear — JAC JS8 Pro
- Drivetrain
- front-wheel drive
- Body
- passenger car
- PSI F / R
- 32-35 / 32-35
- Bar F / R
- 2.2-2.4 / 2.2-2.4
kPa
231 / 231
2.31 / 2.31 bar · 32-35 / 32-35 psi
32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa
Kilopascals show up on some Asian stickers and ISO sheets. 231 kPa front and 231 kPa rear is the JAC JS8 Pro midpoint (100 kPa = 1 bar). TPMS typically warns near 25 psi (about 25% below target). That is already a soft tyre, not a fill target.
kPa, bar and PSI
kPa-led conversions. 220 kPa is 2.2 bar and about 32 psi — handy if this JS8 Pro sticker uses SI units.
| kPa | Bar | PSI |
|---|---|---|
| 207 | 2.07 | 30 |
| 221 | 2.21 | 32 |
| 228 | 2.28 | 33 |
| 231 | 2.31 | 33.5 |
| 241 | 2.41 | 35 |
| 248 | 2.48 | 36 |
| 262 | 2.62 | 38 |
| 276 | 2.76 | 40 |
| 303 | 3.03 | 44 |
| 345 | 3.45 | 50 |
| 414 | 4.14 | 60 |
Estimated pressure by tyre size (225/50R17 and others)
Planning cold pressures for sizes often seen on a passenger car. This JS8 Pro sample opens with 225/50R17, then 195/65R15 and 215/55R16.
| Tyre size | Front PSI | Rear PSI | Front bar | Rear bar | Front kPa | Rear kPa | Note |
|---|---|---|---|---|---|---|---|
| 225/50R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Touring 17-inch |
| 195/65R15 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Very common compact |
| 215/55R16 | 34 | 35 | 2.34 | 2.41 | 234 | 241 | Slightly wider 16-inch |
| 205/55R16 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Typical mid-compact OEM |
| 225/40R18 | 36 | 36 | 2.48 | 2.48 | 248 | 248 | Low-profile 18-inch |
| 205/60R16 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Taller 16-inch |
| 245/40R18 | 36 | 36 | 2.48 | 2.48 | 248 | 248 | Wide touring 18-inch |
| 225/45R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Sport 17-inch |
JAC JS8 Pro placard versus sidewall
Sidewall PSI is a carcass maximum. Recommended operating pressure for this JS8 Pro is the pillar sticker, near 34/34 psi.
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this JS8 Pro.
| Ambient | Gauge (front mid) | Bar | kPa | Note |
|---|---|---|---|---|
| −5 °C (hard frost) | 31 psi | 2.14 bar | 214 kPa | Gauge reads low; do not overfill once warm |
| 0 °C | 32 psi | 2.21 bar | 221 kPa | Gauge reads low; do not overfill once warm |
| 8 °C (UK winter morning) | 33 psi | 2.28 bar | 228 kPa | Gauge reads low; do not overfill once warm |
| 20 °C (set cold here) | 34 psi | 2.34 bar | 234 kPa | Baseline |
| 30 °C | 36 psi | 2.48 bar | 248 kPa | Do not bleed a hot tyre |
| 38 °C (heatwave tarmac) | 37 psi | 2.55 bar | 255 kPa | Do not bleed a hot tyre |
How to set the JS8 Pro
- Measure before the school run, not after the M25.
- Write LF / RF / RR / RL. Do not keep JS8 Pro numbers in your head.
- Add air in short bursts toward 34 psi (2.31 bar) front and 34 psi rear.
- If one corner is 4 psi down, hunt for a nail before you blame the weather.
- Log date, ambient temperature and the four readings.
Load notes
Load moves the rear of a passenger car first. If the factory placard already has a “laden” column, use that instead of these sketches.
| Condition | Front (est.) | Rear (est.) |
|---|---|---|
| Driver only | 34 psi / 2.34 bar | 34 psi / 2.34 bar |
| Full occupancy | 35 psi / 2.41 bar | 36 psi / 2.48 bar |
| Motorway + luggage | 36 psi / 2.48 bar | 38 psi / 2.62 bar |
JAC notes
No special JAC exception: the JS8 Pro uses the door-pillar placard. Size estimates on this page only help if you have left the original load index behind.
Spare and inflator kit
A matching full-size spare on the JAC JS8 Pro usually follows the higher axle (often the rear, near 32-35 psi). A space-saver is commonly 60 psi / 4.1 bar — read that tyre’s own sidewall. An inflator kit is not a spare; check the sealant date.
If the JAC sticker and this page disagree, the sticker wins.
Other JAC models
Questions about this JS8 Pro
How often should I check a JS8 Pro?
Monthly, before a long trip, and after a 10 °C weather swing. Include a full-size spare.
Is the sidewall number correct on a JAC JS8 Pro?
No. Sidewall PSI is a maximum. The JS8 Pro placard is the operating target, near 32-35/32-35 psi.
When does TPMS warn on a JAC JS8 Pro?
Direct TPMS typically flags about 25% below placard — near 25 psi on this row. Fill to the sticker, not to the lamp.
What tyre pressure should a JAC JS8 Pro use?
Catalogue reference is 32-35 psi front and 32-35 psi rear (2.2-2.4 / 2.2-2.4 bar), cold. Confirm on the door-pillar placard.
Front versus rear on the JAC JS8 Pro?
This row is 32-35 F / 32-35 R. Even when they match, a laden rear can justify a higher number if the sticker prints one.
Handbook: placard · bar vs PSI · front vs rear · cold inflation