TECH: TOPICS
Car manufacturers have known for many decades they can make their engines perform with more torque, more power, less emissions and better fuel economy by fitting higher compression pistons. The problem with doing so is the potential to push the engine closer to its limits, encouraging damage and premature failure. For this reason, OEMs equip the powerplants propelling their cars with compression ratio (C/R) suited to reliability, rather than efficiency.
Even so, with very high C/R, an engine would only ever fail when the host vehicle is being driven flat-out on full throttle and in the higher rev range, which would be dangerous and, in all but a tiny number of countries, illegal. Considering the average calculated speed (based on mileages and running hours) of most drivers is close to a surprisingly low 23mph, no damage would occur at lower throttle position and low revs with a higher C/R, but OEMs ignore the benefit of better fuel economy, lower emissions and increased performance in these conditions in order to ensure their engines don't give up the ghost when being driven flat-out, which, with the exception of track day toys, is a condition hardly any are subjected to.
More thanengines are, in theory at least, capable of improving fuel economy in the operating conditions they're almost always driven in, whilst performing well and, importantly, safely at full throttle.
