False reasons for rejecting the 'Blackburn Cycle' or Ideal Explosion Engine

With 8 strokes in the cycle there is more friction and pumping losses - The only way to get more strokes and revolutions is to change the overall gearing. This is obviously not needed and not done. There are simply half as many combustions for cruising and idling. Compare one 8 stroke 'Blackburn Cycle' with two 4 stroke cycles for cruising and idling. Think of total losses per mile, not losses per combustion. A full time 8 Stroke would need 4 litres to equal 2 litres 4 stroke and would have more friction, but this is NOT the 'Blackburn Cycle' concept.

BC is the same as Cylinder de-activation - Both systems can reduce the number of combustions and raise the compression, but there the similarity ends. 9 of the 10 advantages for BC as listed on sheet BC 4, apply only to BC. The 'Blackburn Cycle' is different to the 4 stroke cycle always used by Cylinder De-activation.

Lean burn increases 4 stroke fuel efficiency, while BC runs richer - Lean burn has two effects on 4 stroke engines. Excess air cools the charge at the start of the cycle which helps efficiency, but also cools the combustion temperature which is unhelpful. BC already has a cool charge due to the alternate cool 'air only' inductions, so there is nothing further to gain from lean burn. All heat engines achieves maximum efficiency with a high combustion temperature. This is why BC achieves maximum efficiency in theory and practise with a stoichiometric fuel/air mix.

Emissions - Higher temperature and pressure combustion is more efficient with lower HC, CO and CO2 but produces more N0x. There are several N0x exhaust treatments including urea/AdBlue. For low power the exhaust is like Diesel, with excess air but with less smoke or particulates.

Roughness - BC may benefit from torque smoothing but this presents no problem. It is smoother and quieter than Diesels.

Less power per litre - Using only one of two inlet valve for each induction reduces the max power as BC 1. BC 2 allows high power per litre with 4 valves per cylinder.

Bad evaluation - All aspects of 4 stroke petrol engines are known, but not BC. Engineers evaluating BC, expect to find and are looking for defects. They see a feature, like those above, which could be a defect in 4 stroke engines, but not BC, and reject it.

1,000 tests have been run on a research engine, which can change from the 'Blackburn Cycle' to 4 stroke without stopping. Under identical test conditions average BC efficiency gains ranged from 65% at half load to 92% at a fast idle. This single cylinder engine would not run reliably at a slow idle when the gain would be larger than 92%. How do you improve on 'IDEAL' combustion ?

There are no valid reasons to reject the 'Blackburn Cycle'.