I've read a few on - line features and seen numerous
dyno readings on Leon's for example and as standard they're making considerable more than official bhp figures; 1.4 (138bhp ver) 154bhp, 1.8 (177) 195bhp.
Only through testing on a
dyno can you get an accurate number, and then the
dyno must be calibrated correctly in order to give an accurate
reading.
I just did a cold test on my fresh off the
dyno engine, over the past 20 yrs I've gotten use to zero gap second rings that
read 0 - 4 % cold most of the time and 0 % when warm.
This is inherent due to several factors, which include, but are not limited to, atmospheric conditions (temp, barometric
readings, etc), testing conditions (do they place a fan in front of the radiator, how tight did they tie down the vehicle, etc), type of
dyno (eddy current or acceleration), or manufacturer of the
dyno itself (Mustang, Dynojet, Superflow, etc.).
2010 Honda Civic LX
Dyno Blue Pearl Gray w / Cloth Seat Trim, 16 Wheels w / Full Covers, 160 - Watt AM / FM / CD Audio System, 6 Speakers, ABS brakes, Air Conditioning, AM / FM radio, Bumpers: body - color, CD player, Cloth Seat Trim, Driver door bin, Driver vanity mirror, Dual front impact airbags, Dual front side impact airbags, Four wheel independent suspension, Front anti-roll bar, Front Bucket Seats, Front Center Armrest, Front
reading lights, Illuminated entry, Low tire pressure warning, MP3 decoder, Occupant sensing airbag, Overhead airbag, Panic alarm, Passenger door bin, Passenger vanity mirror, Power door mirrors, Power steering, Power windows, Rear anti-roll bar, Rear window defroster, Reclining Front Bucket Seats, Remote keyless entry, Security system, Speed control, Speed - sensing steering, Spoiler, Tachometer, Telescoping steering wheel, Tilt steering wheel.