You're now mnking an error in your thinking about engines.... and that's compounded, twice!
1) Each dynomometer is calibrated separately; they SHOULD be identical.... but they are NOT! Thus 5.3bhp on one dyno may WELL be 5.5bhp on another.
2) Dyno readings are dependent on SO many variables that the same MOTOR tested on the same dyno on 2 diferent days, with NO changes to the motor whatsoever can read 5.3bhp on day 1 and 5.5bhp on day 2.
3) If you built race motors and calibrated YOUR dyno to read 5.6bhp when it was 'really' producing 5.2bhp.... more people would come to you because you can show HUGE 'headline' bhp figures.
4) A reading of 5.6 bhp tells you NOTHING (except the peak power of the motor at XYZ revs). I'll give examples :--
Take 2 motors, A & B:
Motor A
************
0.5 bhp at 2000 rpm
0.7 bhp at 3000 rpm
1.0 bhp at 4000 rpm
1.3 bhp at 5000 rpm
5.9 bhp at 5500 rpm
Motor B
********
3.0 bhp at 2000 rpm
4.0 bhp at 3000 rpm
4.9 bhp at 4000 rpm
5.6 bhp at 5000 rpm
5.4 bhp at 5500 rpm
.... and you raced those two against esach other on a windy track with a single long straight where you are at 5500 rpm for about 2% of the ENTIRE lap time...... which one would give you the FASTER lap......? There's simply no contest..... motor B would WIPE THE FLOOR with Motor A...... and yet Motor A has the HIGHER 'headline' BHP.... by quite a margin....
So... as you can see, the PEAK bhp is only one SMALL part of the data that you need to assess motors.... You have to assess the 'area under the curve'. That is: imagine making a a bar-chart of the power against revs and make the bars out of columns of paper. The engine which take the MOST paper to make the bar chart is more likely to the quicker motor..... but not at EVERY track.....
Do NOT be fooled by claims about large BHP numbers!
Ian
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