Oldtimer · IHC · Overview
Oldtimer IHC: 2.2-2.4 bar / 32-35 psi
- 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
psi
34 / 34
Catalogue mid-points, front / rear · 2.2-2.4 / 2.2-2.4 bar
32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa
The Oldtimer IHC catalogue band is 32-35 psi front and 32-35 psi rear — 2.2-2.4 / 2.2-2.4 bar, or about 231 / 231 kPa — measured cold. Under-inflation cooks the shoulders of a IHC; over-inflation wears the centre rib and bangs every cat’s eye.
Estimated pressure by tyre size (225/45R17 and others)
Planning cold pressures for sizes often seen on a passenger car. This IHC sample opens with 225/45R17, then 195/65R15 and 245/40R18.
| Tyre size | Front PSI | Rear PSI | Front bar | Rear bar | Front kPa | Rear kPa | Note |
|---|---|---|---|---|---|---|---|
| 225/45R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Sport 17-inch |
| 195/65R15 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Very common compact |
| 245/40R18 | 36 | 36 | 2.48 | 2.48 | 248 | 248 | Wide touring 18-inch |
| 185/65R15 | 33 | 33 | 2.28 | 2.28 | 228 | 228 | Small / older car |
| 215/50R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Plus-size 17-inch |
| 205/55R16 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Typical mid-compact OEM |
| 205/60R16 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Taller 16-inch |
| 225/50R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Touring 17-inch |
How to set the IHC
- Measure before the school run, not after the M25.
- Write LF / RF / RR / RL. Do not keep IHC 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.
Spare and inflator kit
A matching full-size spare on the Oldtimer IHC 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.
PSI, bar and kPa
1 bar ≈ 14.5 psi; 1 psi ≈ 6.89 kPa. Mid-points on the IHC: 34 psi = 2.31 bar = 231 kPa.
| PSI | Bar | kPa |
|---|---|---|
| 30 | 2.07 | 207 |
| 32 | 2.21 | 221 |
| 33 | 2.28 | 228 |
| 33.5 | 2.31 | 231 |
| 35 | 2.41 | 241 |
| 36 | 2.48 | 248 |
| 38 | 2.62 | 262 |
| 40 | 2.76 | 276 |
| 44 | 3.03 | 303 |
| 50 | 3.45 | 345 |
| 60 | 4.14 | 414 |
Oldtimer IHC placard versus sidewall
The tyre-information placard on a Oldtimer IHC sits on the driver’s door pillar (sometimes the fuel-filler flap). Catalogue figures here are a general band: 32-35 / 32-35 psi.
Temperature and a cold gauge
Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this IHC.
| 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 |
Pressure against load
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 | 34 psi / 2.34 bar | 35 psi / 2.41 bar |
| Motorway + luggage | 35 psi / 2.41 bar | 36 psi / 2.48 bar |
Oldtimer notes
No special Oldtimer exception: the IHC uses the door-pillar placard. Size estimates on this page only help if you have left the original load index behind.
If the Oldtimer sticker and this page disagree, the sticker wins.
Other Oldtimer models
Questions about this IHC
Is the sidewall number correct on a Oldtimer IHC?
No. Sidewall PSI is a maximum. The IHC placard is the operating target, near 32-35/32-35 psi.
What tyre pressure should a Oldtimer IHC 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 Oldtimer IHC?
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.
How often should I check a IHC?
Monthly, before a long trip, and after a 10 °C weather swing. Include a full-size spare.
When does TPMS warn on a Oldtimer IHC?
Direct TPMS typically flags about 25% below placard — near 25 psi on this row. Fill to the sticker, not to the lamp.
Handbook: placard · bar vs PSI · front vs rear · cold inflation