It may be seen that the isobutanol and 2-butanol blends allow the most advanced KL-CA50s at the 146 kPa intake pressure condition, while the High Cycloalkanes and diisobutylene blend exhibit the most knock-limited behavior at the same condition.
It may be seen from this figure that the two butanol-based Tier III blends achieved higher efficiencies than the diisobutylene blend and high RON and S fuels.
While most of the tested fuels exhibited a measurable sensitivity to the first fired cycle, three fuels did not: the diisobutylene blend, the High Olefins fuel, and the High Cycloalkanes fuel.
These qualifying fuels include (from an octane perspective) methanol, ethanol, 2-butanol, isobutanol, diisobutylene, the furan mixture, cyclopentanone, and anisole.
Based on the blend result and assuming a high-octane fuel for advanced SI engines would be produced using hydrocarbon blendstocks available today (BOB intended for E10 blending), ethanol, 2-butanol, isobutanol, and diisobutylene qualify as having minimum acceptable properties for blending of a high octane advanced SI engine fuel.
Diisobutylene was more resistant to preignition than benzene, cumene and ethyl benzene at high engine speeds, but worse at lower engine speeds and ignited more easily.
Relative Deposit Ignition Tendency of Various Fuels  RELATIVE DEPOSIT IGNITION TENDENCY OF VARIOUS FUELS Abnormal Ignition Rate, % Relative to that with Isooctane (1) Aspirated Wild Ping Particle Aspirated Teat Results Results by Particle Fuel by Mikita Sabina and Results by Hydrocarbon and Sturgis (2) Mikita (3) Authors (4) Methylcyclohexane 94 (--) Isooctane 100 (75) 100 100 (90) Cyclopentane 119 (--) Xylene 162 (131) 131 Toluene 182 (156) 150 161 (--) Cyclohexane 212 (119) -- (166) Diisobutylene 225 (14) 161 155 (--) Methylcyclopentane 325 (81) Benzene 450 (443) 300 263 (255) Ethylbenzene 500 (411) Cumene 555 (394) 345 Avg of Commercial Gasolines (170) (120) (2) Values shown in brackets arc for 3 ml TEL/gal added to blend.