Combustion engines for GT6

I have an idea of how to implement interesting combustion engines into GT6. The design of such engines should obviously match the design principles of GT6, which is making them an interesting engineering problem.

These combustion engines should obviously also able to run with the different fuels provided by GT or other mods. Making them just one block machines wouldn’t do the mod justice in my opinion, as they would seem very simple compared to burning boxes, which are obviously much more simple in real life than combustion engines in real life.

To make them more interesting challenges, I think it would be best to split the engines into multiple blocks:

The heart of any engine should be the combustion cylinder. It is feed the fuel in the sides and outputs the energy in the form of kinetic energy (not rotary energy) to the bottom. Other than that it also needs to be feed air or other oxidizers into the sides and also outputs exhaust gas to one side.

The exhaust gas and its temperature is different based on the combination of fuel and oxidizer and may contain unburned fuel. The exhaust gas may be used as fuel itself, but needs to be cooled first in that case, the unburned fuel may also be extracted through a distillery. The heat of the exhaust may also be useful.

Spark-ignition fuels: Some fuels may require a spark plug to ignite. The spark plug is a block which is placed on top of combustion cylinders and needs to be powered by electricity. The benefit of the spark plug is, it lets the player easily control the engine with redstone:

  • No redstone signal means no ignition: The engine can be shut of
  • A redstone signal ignites the engine: The engine can be easily turned on
  • The strength of the redstone signal controls the speed of ignitions: Lower signal means lower output power and lower fuel consumption

This makes spark-ignition combustion engines extremely versatile, it is possible to build factories, that only use the power that they need at each point in time.

Compression-ignition fuels: Engines powered by compression-ignition fuels will always run at the maximum speed and compression-ignition fuels are generally more efficient than spark-ignition fuels. These engines need to be turned of by cutting the fuel lines. Turning them on can be a more difficult thing, as they need kinetic power being put into them to start the compression and combustion process.

This may be a problem for coding, as I don’t know if blocks can be producers and consumers of power at the same time and same side, but I am sure this problem can be resolved, maybe creating some special power transmission/conversion blocks specifically for engines.

This system should allow for creating engines of varying sizes for creating specific amounts of rotational power using specific fuels.

Combustion cylinders could of course also be tiered like most other things in GT6. The tiers should be a limiting factor on the maximum kinetic energy produced per tick. Using lower tier engines with very powerful fuel-oxidizer combinations should rightfully cause an explosion. Using lower tier combustion cylinders in spark-ignition setups would limit them to clock the engines at high speeds this way, as that would cause the power output to exceed the capacity of the cylinder and cause an explosion.

Feedback on the idea is welcome.


I noticed in NEI a page for fuel use in a generic “engine” as to opposed to say a burning box so I’m sure something like this is planned.


I do plan on Engines similar to Car Engines, which output Rotational Energy at a higher Efficiency but only for selected Fuels, similar to how Fluid Bed Burning Boxes only accept certain Types of Dust Fuels.

They would definitely have a dedicated exhaust for the Gasses that get created, similar to the Steam Engine exhaust of distilled Water, though I might make the output direction less “Stiff” than with that Engine (as in configurable).

And I do have “NO2 injections” on the same point in my TODO List, so unsure if I gonna add that too or not.

As for the Redstone Part, there is a Mode Selector Cover for such things, I do not want to rely on non-cover based Redstone Inputs, which just could pop up randomly from any other Mods Block.

Though the Engine would be a Single-Block thing, that I will say right away.

And things can accept and emit power at the same time no problem, what do you think Battery Boxes do? :wink:


So sort of the same size as a portable generator then? What would its output be, RU?
Speaking of portable generators would there be another type that outputs EU?

Hm actually I just remembered you can build IC2 generators with a combination of Gregtech parts. They run on solid fuels though.


Using covers for redstone control really seems like a better idea, but also means that there would need to be only one type of combustion engine, which is maybe a good thing to keep one block from being too complex.

Using covers would also provide an easy way to provide oxidizer to the engine using an air vent cover directly on the engine and not having to pump it in with pipes, although that should still be possible, as that would allow for use of oxidizers other than air.

When the whole spark-ignition idea falls away, starting the engine would probably be best done by providing rotational energy to it.

Anyhow, looking forward for what the future of Gregtech holds.


We’re still waiting on proper animations for the current steam engine :wink:


Sorry about the thread necromancy, but I think this topic needs to be brought up again, not to be forgotten. And since I have some new ideas, I think it’s the right time to dig this thread up from the grave.

So the combustion engine. It should be a simple block: One RU output and one RU input opposite of each other. One configurable exhaust on any of the remaining sides.

Why a RU input? Two reasons:

  1. To line up a bunch of engines and add up the power of them. This makes the engines very scalable.
  2. To start the engine of course. Like the burning box, the combustion engine should have some challenge to overcome for using it, and that
    is starting by giving it a spin with the good ol trustworthy handle, or hopefully an electric motor in your case. Stopping it is also not so easy,
    as it once started will keep running. The only way to stop it would be cutting the fuel, which would stop the engine very fast, because it thankfully only has a
    tiny fluid buffer.

A main advantage of the combustion engine compared to the burning box would be linear scalability.
Just line a few engines up with the outputs facing into the inputs and the torque will add up and starting up the engine will be as easy as starting one engine.

The engine should not just need fuel, but also an oxidizer, which can simply be air or pure oxygen for more speed and efficiency. Maybe even NO2 injections. But how to squeeze out even more efficiency or power from an engine? Using better fuels is one option, but how about adding a supercharger? The supercharger is a cover that increases oxidizer consumption, to make the engine more efficient and powerful. It however needs to be powered with a little bit of RU directly into the cover, making the setup far more complicated.

An alternative to the supercharger could be the turbocharger, which is also a cover that can be applied to the engine to raise the efficiency. The turbocharger is taking in exhaust gas, which can be captured by placing a pipe on the exhaust of the engine, to squeeze more oxidizer into the engine. The exhaust is however not consumed, but added to the exhaust of the engine. When the exhaust can’t be output, because the pipe in front of it is full, it will violently explode. To get rid of the exhaust from the pipe network, a new vent cover would be needed, but you still need to keep piping some exhaust into the engine.


Some good points here, I like the hand crank to start an engine and the requirement of an oxidizer.


Yeah some of this is definitely overkill, lol.