Motorsport UK NCR 2026 Edition 1 | Page 324

1.9. SPECIFICATIONS TABLE
PERMITTED FUEL- UNLEADED, SUPER-UNLEADED AND LRG
BS EN 228( Unleaded)
Test
MON( max) 89.0 EN ISO 5163 RON( max) 100.0 EN ISO 5164 Oxygen %( max) 3.7 % w / w Elemental LRG( Unleaded)
Test
MON( max) 89.0 EN ISO 5163 RON( max) 100.0 EN ISO 5164 Lead( max) g / l 0.005 ASTM D3341 / IP362 / EN 237 Oxygen %( max) 2.7 % w / w Elemental
Certain of the above values are additional to those specified in the standards referred to.
PERMITTED FUEL – DIESEL
BS EN 590
Test
Density 15˚C kg / m 3( max)
845
EN ISO 3675 / EN ISO 12185
Cetane Number( max)
60
EN ISO 5165 / EN 15195
Calculated Cetane Index( max)
60
EN ISO 4264
Sulphur Content mg / kg( max)
10
EN ISO 20846 / EN ISO 20884
At the discretion of the ASN the maximum Cetane and calculated Cetane numbers may be increased to 70.0 for National Competitions / Championships
Motorsport UK National Competition Rules 2026 Edition 1
Chapter 8 Appendix 1- Permitted Fuels 324