What is the engine simulation?

1/11/2022 By Josh Willuhn

The Motorift engine simulation is an app that simulates engine performance to predict horsepower.

A legacy version and a beta version are available. The legacy version no longer sees regular updates, the beta version is still new and being tested while development continues.

How it works

The engine simulation uses time proven math to predict horsepower. It takes engine specifications as input - engine size, camshaft profile, cylinder head flow, etc and returns a horsepower estimate.

It calculates the amount of air moving through an engine. You specify a tune to run the engine simulation against and it estimates the power potential.

Like any simulation the accuracy of the results depends on the accuracy of the data fed into it.

Every engine needs a tune

The Motorift engine simulation takes a few tuning parameters. Understanding their role in making horsepower will help you understand how an engine works and predict performance potential. In addition to tuning parameters the engine simulation let's you choose the weather conditions you'll test under. It attempts to predict performance differences including 1/4 mile times. The more accurate your input is, the more accurate the output will be.

The tuning parameters it takes are variables every engine has. They are boost or vacuum level, the air fuel ratio and a BSFC or Base Specific Fuel Consumption.

The BSFC is a measurement of fuel consumption. Read more about it here (Wikipedia)

If you know the stock power output you can effectively estimate the BSFC at peak power and use changes in boost and BSFC to estimate horsepower changes.

Boost is what directly influences horsepower. With the engine simulation you can predict how much boost will it take to meet a horsepower goal.

Air fuel ratio is the last major tuning factor, you can get an idea of what kind of tune will make more peak power.

How accurate is it

In our testing, and assuming accurate Dyno results with a tune to compare to, it is typically accurate within a few horsepower usually about five or ten one way or the other.

Your results may vary and all feedback is welcome and appreciated. Though one star reviews for a free app that only has one unobtrusive ad (for my other app...) does sting in a special kind of way 😂

Other features

Other features included are a variety of calculators for fuel systems, intake throttle body size and carburetor size, exhaust system calculators, camshaft to cylinder head relationship calculations and more.

If you want to blueprint your engine before you build it, hopefully this app will help.

What it won't do

It won't predict how a particular intake manifold will influence horsepower. You can estimate or measure a change in vacuum or boost and estimate it but it doesn't have a list of intakes and how they change horsepower.

It won't give you accurate results based on bad input data.

Where the project has been and where it's going

The first version of this app was a calculator to add up how much an engine build would cost. But it evolved and I had a ton of fun developing it. The "monetization strategy" is largely non-existent, I like cars and started working on them with my dad as a kid. I worked in a few shops too and I have a decade worth of Mustang magazines and fourwheeler magazines to thank.

If you like this app, try my other ones and maybe you'll want to upgrade to premium eventually. But the engine simulation itself is free, the login is to save your engine specifications and do some calculations.

The legacy version or v1 is no longer updated as I focus on the new beta version. Both are available for now but eventually v1 will be replaced completely.

Thanks for trying the app!