can someone please explain why the dyno-graph readouts on this site can show a classic uk scoob turbo with no modifications recording up to 238bhp when the official figures are only 218bhp?

 

acccuracy of dyno measurements / build tolerances in the engine / weather conditions...

The list is quite long and the few I gave aren't exhaustive.

Car manufacturers have to be a little conservative with performance figures - the quoted figure is probably an average found during testing of new engines, or a Subaru engineer's educated guess...

Also, depending on weather conditions / the operator etc. dyno results can be subject to errors in measurement.

 

Variance in rolling roads.......
Conditions, hot vs damp
Fuel 97 vs 100

 

Optimistic dynos.