Quote:
Originally Posted by vex
That's very peculiar--assuming your correct one should be technically able to ship out the eccentric shaft and have it tempered. However, bending an E-shaft would seem counter intuitive if I'm imagining it right. Where exactly was the bend and how did you measure it, was the bend .006" from the front or was the measurement dictating that the shaft was out of spec by .006" in the front?
I ask because I would be very surprised that the stresses seen are orders of magnitude higher in a turbo built engine compared to the redline of the eight. Do we have the material mazda uses for the E-Shaft (what specific steel they use, etc)? I'll be happy to look up the stats on the material and see what forces would need to be present in order to deform it. I would also think that the REW's shaft would endure more stresses since it's rotational impulse is higher than the 8's (the .6lbs being more weight that needs to be spun up and down depending on the throttle puts more axial stress on the bearings--though the .6lbs may be of no effect or worry).
While doing google searches I came across this:
This is for 20B engines, but I believe the principle is still applicable. Was the original engine Pinned or Doweled?
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Ok, well some of your logic is flawed. The rx8 is an na engine with a low combustion pressure putting less stress on the shaft. You increase combustion pressure and you increase forces on the shaft. So for the sake of argument lets jump into black and white for a second. Combustion pressure basically aquates to torque, if you increase it the tourque will increase increasing the force aplied to the rotor, bearing and shaft. So with boost you increase combustion pressure. So with out the turbo you have less force on the shaft even at 9k.......Not to mention the torque on a renisis is well we all know that ./
Now if the shaft is bent .006 it is out of :mazdaspec" by .0045.
The shaft being bent .006 at one point of the shaft would give you a diameter of .012 meaning the shaft is digging .006 all the way around pushing the rotor out of place destroying the bearing etc.