![]() ![]() Not only is the exhaust cooled right next to the engine there’s a gasoline particle filter (GPF) in order to comply with the latest emissions regulations in Europe. Most manufacturers try to jam their catalytic convertors as close as possible to the engine to make the car more ecological, but Toyota decided to be different. Another thing I like is that, at least on top this overly complex design, there’s a metal cover and not plastic junk like on the rest. There’s a bunch of rubber hoses, and except the evaporative emissions control (EVAP) line that wraps around the engine, tall of the, seem to be easily accessible. Longevity is questionable, but according to reliable sources, from what I understood, Toyota rates this engine to last 250,000km (just over 150,000 miles) and in the past Toyota has been exceeding their “expected lifetime” estimations by x1.25 to x1.5. In summary, with all the passageways, for hot exhaust gases, with an exhaust manifold, two separate cooling jackets, and the fuel and vacuum pump all integrated into one thing – (not to forget the obligatory oil lines, and variable valve timing systems) this is a very complex, thermally loaded and probably almost unrepairable, interesting design. – Repairability might not be great on this design, but they just rarely cause issues anyway. Also, in a similar fashion to the Camry 2.5L, the valves are driven using rocker arms with valve adjusters. The construction of the valvetrain seems to be very similar to the 2AR (2008-onwards) Camry, where the camshafts are contained in a house that’s separate from the head. It is unclear to me if a failing fuel pump, as I see it, if plunger gets shifted and will work unevenly it could theoretically cause damage to the engine’s exhaust camshaft. The fuel pump is driven directly from the engine’s exhaust camshaft, is driving what seems to be the tappet roller. This is not all that unusual, fancy Volkswagen cars had this feature for the last 5 or so years – this integrated cooled exhaust theoretically results in less engine wear during startup (important for making short city hops), faster heat up and better economy, although this does mean there will be more load on the cooling system (which is already extraordinarily odd on this engine anyway) What’s different with the new Toyota Dynamic Force, is the integration of many components into the engine’s head, there’s an integrated exhaust gas recirculation (EGR) passage and an exhaust manifold with two separate cooling jackets also drilled inside the head. Modern, efficient, integrated, But will it last? ![]() Most of the information I used I got from other mechanics and the absolutely great articles about the M15 (R3) and M20 / A25 (R4) engines on. I am not an automotive engineer, neither am I a physicist or a chemist, so I'm probably not that qualified to make assumptions on it's inter-workings and reliability, but I am trying to make sence from this all - Feel free to add any information or correct any mistakes I might have made! ![]()
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