Ahh the ignorance is bliss theory in practice.
My man a 20 bhp loss is something I would expect on a 180 - 200 bhp fwd machine.
Scan the page if you want, no doubt the ambient temp was hotter than the arse of the sun, the humidity was so high you were wearing snorkels and the barometric pressure was higher on the moon.
57 at the wheels is in the 60s. Not the 70s or above.
A standard 1.8 16V should be putting out in the mid 120s if the engines at standard power. Like the E6J engines should be putting out low 70s at stock 80bhp power.
A fwd box will lose about 12 or so %. A 4wd about 20% and rwd about 15 - 20% depending on the car. These are real actual losses not the max power sh*te.
No doubt you shall scoff at this and claim I am an idiot, but I assure you sir I am no muppet.