aero expert 807 wrote:
From fia regulations:
ARTICLE 5: ENGINES AND KINETIC ENERGY RECOVERY SYSTEMS
5.3 Engine dimensions:
5.4.1 Cylinder bore diameter may not exceed 98mm
this implies that cylinder bore is flexible
good point !
I guess that they are all the same bore and stroke now (we shouldn't have to guess) ?
Renault were a smaller bore surely ? how/when in thie 'frozen engine' era did they make the change ? on durability grounds ?
minimum bore spacing rules were presumably written around these engines (as were the rpm rules ?)
if they still use the smaller bore they have done well on durability, their stresses would be higher
heat loss to coolant would be lower, but frictional losses a bit higher, and valve area less
nearly 30 years ago Honda had an even higher B:S ratio in their NR500 GP motorcycle
this had wildly non-round 'cylinders' with 8 valves etc (to subvert 4 cylinder limit), and was not great
current B:S results from (unprecedented) decades of engine rule stability after the elimination of turbos
totally logical, but extreme B:S would not work (with single ign) without high combustion speed fuel (last 20 years)
presumably this factor prevents even higher B:S, and normal fuel would not support current B:S
the current F1 engines are brilliant and logical (enabled by their remarkable gearboxes, sorry autogyro!)
their valve sizing breathes so well that they really use their revs ie the gearboxes enable this 'half a powerband' setup
(historically engines eg V12 did not breathe and/or combust well enough to use well their higher rpm potential)