Quote Originally Posted by Porscheman
Quote Originally Posted by DoktorB

All M engines, apart from S65 and s85, share block designs from their standard road car counterparts.

The new engines in the current M5/6 and forthcoming M3/4 are no different and will be modified and tuned in the same way you have mentioned above. They have to be modified with stronger internals as they produce over 100hp more than the standard engine.

The S65 and S85 were different in that they were completley bespoke to the M cars they went into.
The new engines are not built in house by bmw motorsport and will not be modifyied and tuned internally like the previous M Engines

The current engines are not proper race engines but previous engines were
Are you sure about that??

BMW seem to disaggree.

Download and read this pdf.

http://www.google.com/url?sa=t&rct=j&q=bmw%20s63%20difference&source=web &cd=11&ved=0CCkQFjAAOAo&url=http%3A%2F%2Fwww.m5boa rd.com%2Fvbulletin%2Fattachments%2Ff10-m5-discussion%2F194817d1360766519-s63tu-engine-technical-training-s63tu-engine.pdf&ei=kfkAUuCUFunhygGqm4GwAw&usg=AFQjCNHxz 6xO6sJplVASvGVlRasjCtREDQ