hmm
~2592 Watts for fighting the road
and
~3237 Watts fighting the airdrag @50mph *
makes
5829 Watts ( almost 8 horses)
that will need to hit the road
with a 44 magnum TC you will at least loose ~23% of the motor power to belt slippage
making the targeted motor power in the realms of 7600 Watts at the very least.
No IDK how good the transmission still is in terms of efficiency, but I'm guessing another ten percent is easily lost
So
8500 Watts is what Im guessing you'll need to tickle from that poor 212
11.5 horses or thereabouts
in short: you need to almost double the output power if you want to reach the 50mph mark.
possible, true true, but not exactly easy
mostly because you should not insanely increase the rpms as most performance mods do
you need a thumper instead... (else you loose more to belt slippage and gain very little if anything at all at the wheel..)
plus thanks to the 5 speed you don't actually need high rpms at all
I'd suggest to increase compression, decking the block, maybe thinner head gasket
and in case it fits an oldschool Honda GX160 head (the 14cc one)
billet conrod is highly recommended since that amount of compression does not play nice with cheap chinese casts
up until now I'm guessing we're in the solid 8-9horse range
a low rpm increased lift and duration cam (unchanged timing i.e. custom ground)
with a somewhat bigger (say gx390) carb and some nicely cleaned
least restrictive intake and exhaust should crack the magic ten...
I'm unsure how you could actually get the last few watts from just torque tbh..
maybe bigger valves and a smidge (just a smidge mind you) higher rpms (4500-5000 max)
with certainly no more than 4° timing advance really (maybe 2° is even better if any)
just to move the torque curve over just ever so slightly to high rpms
without having to sacrifice lots in the low rpm range...
but yeah tough call to get reliable 11.5horses from mostly torque (rpms is easy but won't help you anything really I'm afraid)
this ain't going to be cheap
but yeah... that might actually work
'sid
* assuming here cw of 0.28 and 1.7m² of frontal area abouti'sh no?
PS funny I think an old stock ungoverned gx270 with just intake and exhaust might do the trick .. cheating? yeah, maybe but still
[
EDIT]
Oh wait we can make some assumptions...
16.5m/s current top speed.. (37mph... assuming 35 up the small inclines and 39 down ... 37 reliable level road speed)
all else being equal that means
you needed
1293 Watts to fight airdrag and
1910fighting the road
3203 Watts are actually on the wheels in your test,
assuming a "close to spec" predator 212 with 4600 Watts of output power
your efficiency is only 69.6%
no matter how wrong my above estimation was about cw and frontal area and efficiency of the transmission and so on..
it should remain about the same (unless you can reduce that somehow)
sooo needing 5829 Watts on the road the engine needs to provide
8380 Watts 11.4hp (hah.. all the hassle from calculating for 0.1horse... what a waste of time LOOOL)
that's an "insight", right? I'll need to find the exact air-drag specs for it..