The outgoing Mazda 3 interior looks really cheap. I wanted some thoughts on Mazda's SkyActiv motors. They look very innovative and built very well. I researched in depth about Mazda's GDI system. The internals of the engines must be robust since the compression is at 13. I have looked into various GDI systems. The CX-5 is powered by Mazda's 2.5-liter SkyActiv four-cylinder engine, which makes a peppy 184 horsepower and 185 pound-feet of torque. The 2.5-liter is mated to a six-speed automatic transmission.
The quickest and easiest way to lower the compression ratio is to put a thicker head gasket in. The two problems with that are: 1) Finding a thicker head gasket. 2) Doing this may change can timing or maybe make the timing chain not fit any more. Those two things may end up making this not the simplest strategy.

The overall longevity of this engine is considered to be about 250,000 miles. After that point, the 2.5L Mazda engine is not considered economically wise to use. We've seen a couple of other Mazda models equipped with this engine having 200,000 plus miles on their odometers.

The point though was that the turbo from Mazda wasn't designed to produce maximum BHP. The turbo doesn't do any "harm" to the engine ever The boost provided by the Skyactiv turbo is certainly not "minimal" - maximum boost from the factory is 17.4 psi, or 1.2 bar. Obviously, you don't understand what boost is.
Well, consider this. The compression ignition engine makes 15.8 percent more power. That efficiency gain is effectively coming for ‘free’, in engineering terms at least. Suddenly Mazda’s claim that the engine is between 15 and 17 percent more efficient than the Skyactiv-G is objectively borne out.
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is the mazda 2.5 skyactiv engine reliability