Multifuel engine combinations

This has been done in a few different applications in the historical past, to make this post quick, the idea is that vehicles that run multifuel cost more to build but greatly reduce costs of operation. When travelling an interstate at a standard speed, the engine does not need a high octane fuel, wide open throttle getting on the interstate would require the high octane fuel, so for a 100 mile interstate trip, 1/4 of a mile needed 4 dollar per gallon gas while the other 99 and 3/4 miles needed 3 dollar per gallon gas. Starting in the 1950’s a multifuel carb would allow a manually adjusted mix between 85 octane and the top octane available for the time period. It would allow for performance when adjusted to that setting, or when on an interstate, dialed back with a dashboard knob to the cheapest fuel setting possible that is not causing detonation. It can progress through a more vacuum setup in the 1960’s and be as a premium MFI that does all of these adjustments automatically, and finally work in the EFI and DI worlds as a port and direct injection using two nozzles per cylinder. It would increase initial ET costs and production, but it would add to the player experience in campaign mode. The earliest models would negatively affect drivability, the vacuum MFI models would increase service costs (finnicky), the later models should only be an ET and production units increase. Thoughts?

Which production cars had this feature? I’ve never heard of it and I’m not clear how it works. You had two separate fuel tanks filled with different octane, and the system would switch back and forth?

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most petrol powered cars can be converted for use with LNG/ LPG

in that case a second tank is installed into either the trunk or the space usually occupied by the spare wheel (which in turn is replaced with a tyre repair kit)


It has mostly been used in military applications, and things like tractors. The ford model T had an air fuel ratio knob that would adjust for any combustible fuel, because during the 19teens oil companies were cutting gasoline with kerosene to make the product stretch. What we are adding to this is the development of an on demand fuel octane increase for the load demand. In this alternate reality we can pretend cars have a 2 gallon ethanol tank and a 20 gallon petrol tank. Depending on driving habits depends on the fill ratio. Through the modern era, many pickup trucks had twin tanks, and my father would do as I say because he had a mild build on a ford 460 so he would use 87 octane on the flat and 90 when we were going over the Appalachian summit or anything like that. He was an engine builder. 360 horsepower is not a lot today, but on a carburetor that was getting somewhere.

Diesel trucks do that with propane also.

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that case probably is far less common though
(never heard of it)

What it gives diesel owners is the option to multifuel when propane is cheaper to buy. It extends a gallon of diesel another 15 percent, and also can be turned up to make more power. Propane Injection For Dodge Ram Cummins Turbo Diesel - Mopar Muscle Magazine


though to be honest, i see little gameplay value for a LOT of added work on both dev and player side

the devs need to implement the multifuel choice having two different octane levels and the player effectively needs to tune two engines for one trim

even then that tuning is nigh-impossible given that currently you can only touch ignition timing and fuel mix (or that one slider replacing it) without having a separate engine entirely


I have to agree. Automation is about building mass produced passenger cars and trucks. It’s not really about building oddball military vehicles or tractors, or doing weird aftermarket conversions. This sounds like it would take up a lot of valuable UI space for a feature pretty much 0.0% of actual consumer vehicles use. There’s already so much actual car stuff that’s currently left out of the game (e.g. why can’t I have a limited slip in my 1960s muscle car?), that I can’t see this ever happening.

There is no modeling needed for this. This is all applied math. There are hundreds of thousands of military vehicles who all use these concepts. The willys jeep that won WW2 ran on anything between gasoline and kerosene. The tractor, a 1953 ford 8N in my barn has the same engine, which has the same multifuel engine. There were millions produced. In the game they have already put in a “tune for this octane” slider so the code is already partially wrote.

But Automation is neither about tractors nor military vehicles.

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Of course automation is about tractors and military vehicles. Their challenges even included building an engine for a generator as a military contract.

That’s kind of a stretch, man. Gran Turismo had a moon buggy mission, that doesn’t make it a space game that should have spaceships. A simplified engine building tutorial doesn’t make generators a core part of the game. If it’s about tractors, where are the tractor bodies? How do I get a military contract anywhere else in the game? I can appreciate wanting a feature that would be neat to play around with, but that doesn’t mean it makes sense.

Nothing is “just” applied math though. It takes time and effort for the devs to apply the math, then it takes time and effort to implement that into the UI, then more time and effort to test it and make sure it’s fun and bug-free. Just take a look at turbos. The new update doesn’t have much in the way of modelling - it’s mainly “applied math”. It still took ages to do, because math and programming aren’t trivial. This wouldn’t be as intensive and complex as turbos, but it’s still not free.

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As silly as this may sound, if it goes into game, where there is good reason for it - I used to have the 7x game multiplier and would complete it by starting with building a reasonable heavy delivery, then build a sports car around the engine. These would also be long term commitments like that in the campaign. If there is research investment in dual fuel rails by 1984 in automation universe then it becomes a win. Bit my idea of the automation universe is much more complex, with the idea that a factory putting put a piston can supply four engine factories using that piston, like a realistic Continental manufacturing and supply chain.