What transmission loss did you assume when you converted RWHP to crankshaft HP? The conservative number is 15% but 20% is good if you want to boost the number.
Here in the USA some dynos such as Dyno-mite have a reputation for giving conservative HP numbers and others such as dynojet are known for giving bigger numbers. Also dyno operators have the means to fudge the numbers. One problem is that many dyno's are owned by businesses that build special motors and it is good for them if the dyno is generous. I am fortunate in that I have friend who owns a dyno for his own use (he is a surgeon) and he has no interest in artificially boosted numbers.
A few years ago a guy over here bought a race motor from Alfaholics in the UK with a stated HP output but it made considerably less on a dyno over here. I think that it was Mike Besic's dyno. I know that Jim Steck does countless runs on his own engine dyno before he delivers a customer engine and then the car might go on Mike's dyno for comparison. It has become a standard of comparison for some of the US Alfa fraternity.
76 Suzuki GT500
2011 Jaguar XKR
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