In german forums are recent speculations that the leaked engine pics posted here, didnīt show the new M3/M4 engine but the also new M340i/M440i engine - based on an N55 succesor !!!
This specs are based on insider-informations, that the M3-Testmules are also used for development of the N55 succesor - for the M Performance Automobile F3x and later the .35is. So also the "F80M3" fueled with E85 in sweden could be one of this engine-test-cars. The use of the "F80" body was logical because the N55 succesor is/was for sure one candidate for the M3/M4 engine - in its highest developed form ... but it didnīt says for 100% that this engine was also really choosen.
This let german forums speculate that there is already an chance that the new M3/M4 gets an other engine than the "here confirmed" I6 - also BMW/M-GmbH insiders considers other possible F8x engine variants ...
for me this are good news.
The M3/M4-engine is already the biggest BMW secret until now ... only time will tell us the truth.
Greets Uli_HH