Bristol · 405 · Bar

Bristol 405 bar chart (2.2-2.4 / 2.2-2.4)

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

bar

2.31 / 2.31

32-35 / 32-35 psi · 231 / 231 kPa

32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa

2.3 bar is not 23 psi. On this 405 2.2-2.4 bar converts to about 32-35 psi. Use the table, not a guess. A 10 °C overnight drop takes roughly 1 psi (0.07 bar) off a closed Bristol tyre.

Bar, PSI and kPa

Bar-led conversions around the Bristol 405. 2.2-2.4 bar is not “32-35 divided by ten”.

Bar	PSI	kPa
2.07	30	207
2.21	32	221
2.28	33	228
2.31	33.5	231
2.41	35	241
2.48	36	248
2.62	38	262
2.76	40	276
3.03	44	303
3.45	50	345
4.14	60	414

Bristol 405 placard versus sidewall

If the Bristol sticker is painted over, the handbook is next. This website is a map, not a replacement VIN label.

Estimated pressure by tyre size (185/65R15 and others)

Planning cold pressures for sizes often seen on a passenger car. This 405 sample opens with 185/65R15, then 215/50R17 and 215/55R16.

Tyre size	Front PSI	Rear PSI	Front bar	Rear bar	Front kPa	Rear kPa	Note
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
215/55R16	34	35	2.34	2.41	234	241	Slightly wider 16-inch
245/40R18	36	36	2.48	2.48	248	248	Wide touring 18-inch
225/50R17	35	35	2.41	2.41	241	241	Touring 17-inch
205/60R16	34	34	2.34	2.34	234	234	Taller 16-inch
225/40R18	36	36	2.48	2.48	248	248	Low-profile 18-inch
205/55R16	34	34	2.34	2.34	234	234	Typical mid-compact OEM

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	34 psi / 2.34 bar	35 psi / 2.41 bar
Motorway + luggage	35 psi / 2.41 bar	36 psi / 2.48 bar

How to set the 405

Park the Bristol 405 for at least three hours (cold tyres).
Use a calibrated gauge, not the only meter on a forecourt hose.
Set the placard for that axle — about 32-35 psi / 2.2-2.4 bar front and 32-35 psi / 2.2-2.4 bar rear on this catalogue row.
Recheck all four. A 2 psi miss on a front-wheel drive 405 is enough to feel a pull.
Refit valve caps and reset TPMS if the handbook asks for a relearn.

Temperature drift

Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this 405.

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

Bristol notes

No special Bristol exception: the 405 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 Bristol 405 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 Bristol sticker and this page disagree, the sticker wins.

Other Bristol models

408

Questions about this 405

What tyre pressure should a Bristol 405 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.

Should I bleed pressure after a motorway run?

No. Heat raises the gauge. Set cold only. Bleeding a hot tyre leaves it low the next morning.

What is that in bar and kPa for the 405?

Mid-points are about 2.31 bar (231 kPa) front and 2.31 bar (231 kPa) rear.

Front versus rear on the Bristol 405?

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.

What PSI if I plus-size toward 215/55R16?

Keep load index at or above OEM. Low-profile sizes usually stay at or slightly above the placard. Use 185/65R15, 215/50R17 and 215/55R16 as a planning band.

Handbook: placard · bar vs PSI · front vs rear · cold inflation