PaulFitzwarryne

There never was an official rating. Mazda US used 101hp@6000rpm and 107@ 4000rpm for torque in their publicity for the GSL. This was a slightly inaccurate calculation from the factory data which was given in JIS not SAE measurement. The original data was marginally pessimistic, and of course depended on atmospheric conditions, as does any dyno performance, and fuel quality.

What really matters is rwhp. I once went to a club dyno day where there was surprising 11hp difference between stock 12As, which were all the 'factory' rated 114hp Jspec engine.Ex factory I would have expected around 5% difference from the interaction of tolerances. If I was a cynic I would also say by day of week manufactured.