Does compression ratio affect exhaust note? I have seen a few older Mazda 3 with different cat backs that sound kind of ricey, but seems that the newer ones - specifically the Skyactiv - seem to sound deeper and less crackly... is this due to the higher compression ratio of our Skyactiv...
So I've got a 2012 Mazda3 Skyactiv 6MT with about 15k miles on it. During the course of our time together I have noticed something slightly distressing - when downshifting into 2nd, the engine rev's sometimes will jump unnaturally. I can attempt to speculate about how maybe the ECU has...
I am still learning the ropes on driving a stick shift and my hardest point is not putting so much pressure on the pedal so I am not over-revving the engine from a stand still into 1st gear. My friend who has been helping me even noticed that it was very sensitive compared to her nissan maxima...
Not sure if this should go in the Engine and Performance forum but it didn't seem to fit there.
I'm wondering if anyone knows how the compression reduction from 14:1 to 13:1 (CX-5) to 12:1 (Mazda3) is actually achieved? Is there something physically different with the engine like...
So did a compression test last night, warm engine but colder ambient temps
First test 80~° warm engine
Last night 54° warm engine
Now this is at like 6300ft asl, but still these are really low numbers for 9.7:1 it should be in the 180+ range right?
decided to check my plugs today anyway I did a compression test while I was at it, just wanted a baseline of what the cylinder pressure was. ( I know that cams have alot to do with changing it )
Now the results were interesting.. anyone care to chime in
Cylinder 1 : 130
Cylinder 2 : 130...