In the second linked article (http://www.manufacturingcenter.com/...2/0102laser.asp) it was mentioned that:
"Its potential for engines has not gone unnoticed by the Big Three automakers who are integrating the process into their transfer machining lines in the U.S. and Europe. Initially they have targeted diesel engines because of the ability of laser honing to dramatically reduce emissions."
Does anyone know to what extent that this technology is being used (i.e. what model engines other than diesel...etc.)?
Also, specificly, why the top half of the cylinder walls only?...

 

They laser structure the part of the cylinder that the rings seat against. No reason to structure the bottom part, where the piston skirt just slides, IMHO.

A.

 

On high end racing engines, all possible accessories are bolted to the block while honing, also. Basically it just simulates the same principle as using a torque plate, but to an extreme factor.

 

To my knowledge, no gas engines yet. The diesel guys have some tough emission standards coming up, and they are looking at everything. The folks who make cat cons are using that technology but in a different way for diesels.

My guess would be we'd see it on the highest tech, highest rpm gas engines first. Maybe the BMW M-3 engine, but I've not heard.

Z28tt 's right on the top half.

 

as far as the gas engines, i would say possibly lemans and open wheel cars might be using it, if you used it on all the parts (gears, etc.) it would definitely reduce the hp loss at the back wheels, the only reason i can guess they would only use it on the cylinder walls would be because the rings have to seal, and the better fit, the better seal