ive noticed that as well, nzarnow

 

I remember seeing 125kg for the Renesis engine (not sure about its accuracy though). What does the Toyota engine actually weigh?

2 advantages the Renesis would have over the Toyota engine is its flatter torque curve and its lower center of gravity and without a pinion it would probably have slightly less drivetrain loss than what it has now.

And again, it would be nice to have a Miata with a Renesis engine. But this has been discussed before many times.

 

The engine would probably cost at least twice as much.

 

I think if Mazda could have fixed the aluminum/cast iron thing 100% they would have. So many
people are used to running out, starting their engine and being halfway down the street before any warming has occured. I think it's a miracle Mazda engineers were able to make this thing work at all. There is such a large surface area those side seals sweep on the side housing, I've always assumed that was why break in is so important. And I have been facinated about the stories of cars going 200,000 miles on original engine thinking, "why was this car so long lived"?
Is it just a sweet original build? An exactly proper break in? Perfect maintainence ? Perfect warm up and cool down? or a combination of all these things. Those cast iron housings are sure heavy.