IF you could get a 6.20 Rod in there you would have a 2.06 rod ratio... and a very light reciprocating assembly (the compression height of the piston is going to be short, yielding a shorter lighter piston) which will maximize the power output, lightening the recip assem minimizes the parasitic power loss of accelerating 8 pistons from a dead stop 2 times per revolution... (at TDC and BDC the piston comes to a complete stop), therefore any reduction in the mass, having to be accelerated, is going to yield a net power increase...
Another factor is the higher rod ratio allows the engine to rev higher with less side loading... if the effective RPM's are increased then the whole mass acceleration issue becomes an even larger factor...