Honda BF90D year2010

Honda states that they use the same engine for the Honda BF90D year 2010 15vtec as the Honda Fitt/Jazz. i would like to ask these engines that i found and are used on the same cars with the same Displacement: 1,496 cc (91.3 cu in) and Bore x Stroke: 73.0 mm × 89.4 mm (2.87 in × 3.52 in) but with different power. could some one tell me what is the difference in these engines to have different Hp.

[h=3]L15A2 i-DSI[edit][/h]It debuted in Honda City/Fit Aria four door Sport-sedan in November 2002.[SUP][2][/SUP]

• Offered in the Fit Aria and Partner in Japan.
  • Displacement: 1,496 cc (91.3 cu in)
  • Bore x Stroke: 73.0 mm × 89.4 mm (2.87 in × 3.52 in)
  • Compression Ratio: 10.8:1
  • Power: 66 kW (90 PS; 89 hp) @ 5,500 rpm
  • Torque: 131 N·m (97 lb·ft) @ 2,700 rpm
  • Top Speed: 180 km/h Speed Limiter, 240 km/h Sport mode
  • unleaded gasoline only
  • Source http://www.honda.co.jp/auto-archive/fit-aria/2005/grade-data/

[h=3]L15A1 VTEC[edit][/h]

Stock L15A1-VTEC engine​

It debuted in JDM Fit and Mobilio Spike in September 2002.[SUP][3][/SUP][SUP][4][/SUP]

• Available in the Fit, Fit Aria, Airwave, Mobilio, and Mobilio Spike in Japan. Sold throughout the world with 5-speed manual or CVT options in the Fit/Jazz and City. Canadian and US Fit models will have a 5-speed automatic instead of the CVT.
  • Displacement: 1,496 cc (91.3 cu in)
  • Bore x Stroke: 73.0 mm × 89.4 mm (2.87 in × 3.52 in)
  • Compression Ratio: 10.4:1
  • Power: 81 kW (110 PS; 109 hp) @ 5,800 rpm
  • Torque: 143 N·m (105 lb·ft) @ 4,800 rpm
  • Top Speed: 180 km/h (Electronic limited)
  • Rod Length :149 mm
  • Rod/Stroke ratio: 1.67
  • Pin Diameter: 18mm
  • Comp Height : 1.030

[h=3]L15A7 (i-VTEC)[edit][/h]

• • SOHC 16 valve i-VTEC
  • Displacement: 1,496 cc
  • Bore x Stroke: 73.0 mm × 89.4 mm (2.87 in × 3.52 in)
  • Compression Ratio: 10.4 : 1
  • Power: 88 kW (118 hp) / 6,600 rpm
  • Torque: 145 N·m (107 lb·ft) / 4,800 rpm (GE8 Fit)
  • Carbon Dioxide (g/km): 148
• Honda Fit (Japan series GE8 / 9)
• Honda Jazz (Brazil,Thailand GE8 / 9)
• Honda Freed (Japan series GB3 / 4)
• Honda City (India, Brazil, Pakistan, Thailand, Malaysia, ASEAN)
• Eligible for the F1600 Championship Series

Computers controlling ignition timing,valve timing,fuel injection pulse length. Also injector sizing,compression ratio come into play amongst other factors

I think johnnyjgr states it fairly well. Also notice the 16 valves in the last version listed. That's increased air capacity and the more air you can move the more fuel you can introduce. But, if you look at the horsepower value for each engine it appears each was maxed out at different engine speeds.....the 16 valver was turning 6,600 to get it's added horses with the engine listed above it turning 800 rpm slower and producing almost the same torque. I'm sure the variables are many.

In all honesty, this is a question that is WAY above my pay grade to answer ACCURATELY.

Thanks for your reply and info