the rules now (fueling by rpm for all rpm) amount to fueling-by-piston speed (because the stroke is fixed by rule)vorticism wrote: ↑Sun May 25, 2025 8:10 pmReminds me of how, what you might call “free redline” rules led to ever higher engine speeds in F1.
Piston speed is easier to calculate than piston inertia and in some cases easier to explain. Being 50 years before computers and digital calculators, perhaps that’s why the metric became a common frame of reference.
if stroke was free the same fueling-by-piston-speed might allow higher rpm via reduced stroke (and capacity) ....
even a more 'range extender' type of ICE
(assuming the designers can extend their combustion trickery to higher rpm)
btw 1
on YT Dominic Chinea is having trouble converting his Liberty (45 deg) V12 into a V8 - many think he should L6 or V6 it
as a V8 it won't vibrate worse than (successful) 90 deg 300 hp Wright-Hispano V8s (& better with some counterweight)
a 45 deg V twin is bad for primary imbalance - but these will cancel in a 45 deg V8
(a 90 deg V8 with flat crank is the worst for secondary imbalance)
and yes the Liberty V8 would be torsionally bad with an airscrew - but not so in a car
reforging the original unweighted V12 crankshaft into a 'flat' V8 counterweighted one should be interesting
https://www.jstor.org/stable/pdf/44720513.pdf
for 80 years medium-speed 45 deg V8s diesels were made for railway locomotives eg EMD 2 strokes & ALCO 4 strokes
ALCO used flat counterweighted cranks (the 2 strokes had counterweighted camshafts)
btw 2
