Grant:
CGX car nut:

Speculative on one's part; however, looking at potential cost savings from sharing components for a limited edition model, it makes some sense to utilize those newly developed heads from the M139 engine.  The M139 is fully developed, meeting current emission and other regulations with the heads and ancillary components being costly.  Using the flat crank configuration is the equivalent of two four cylinder motors with a common crank, AMG meets its performance parameters comfortably with a large safety margin.  

Makes sense.  And the large safety margin will certainly be exploited by Renntech and other tuners (maybe they'll even raise the redline which must have lots of margin if Ford can spin a much larger engine more than 1,000 rpm higher)...


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18 GT3 Manual, 73 Carrera RS 2.7 Carbon Fiber replica (1,890 lbs), 06 EVO9 with track mods. Former: 16 Cayman GT4, 73 911S, Two 951S's, 996 C2, 993 C2, 98 Ferrari 550, 79 635CSi

 

However, if the valve train doesn’t have any more headroom for a higher RPM limit than that is a fixed variable.  The M139 has the same redline.