This is a work-in-progress! Please contact us with any bugs you may encounter. JavaScript must be enabled for this to work.

What the heck is a “dyno generator”? It’s a tool to emulate your engine’s output with various modifications. Originally it was named “gyno”, but we decided against that for… numerous reasons. There are only a few engines available at the moment, but we do plan to expand this in the future.

This is only an estimating tool! It in no way guarantees these numbers will show up on a dyno. These are only generalized numbers to help figure out your build needs or goals, though generally you should see numbers within 10% for most products. This is a great tool for sizing what injectors you will need for your build, especially when used in combination with our Choosing Injectors page/tool.

All numbers are estimates, and displayed in horsepower at the wheels (WHp) and assumes premium pump fuel (91-93 AKI/95-97 RON) is used.

Sometimes you may need to hit “Run Dyno” twice in order to correctly apply all mods.

Couple of points to discuss really quickly!

  • Only works in 500 rpm increments at the moment, so rev limits and Hp values will be rounded to nearest interval.
  • For M20 with B27 bottom and B25 top, choose M20B257.


  • 0.4.22
    • Whoops! The last revision accidentally had M60 set to 6 cylinders. Fixed to 8 cylinders.
  • 0.4.21
    • Numerous fixes to compression and displacement calculation.
    • Improved estimation of engine output above stock rev limit.
    • Overall improvement to F/I estimations.
    • Added popular “M20B257” engine build to standard engines.