Well, hold on. Let’s put aside the issue of valvetrain modularity, since that’s something I’m fine with. I want to talk specifically about having a variable cylinder count.
Currently, there is no advantage to making engines that have the same bore and stroke dimensions. Sure, you can get a familiarity boost between I4s and I6s, or V6 90 and V8 90, but those engines can be totally different otherwise. I can totally optimize the bore and stroke of the two different engines for different purposes. Why the hell should BMW use the same 0.5L cylinder for all their engines? Why the hell should Alfa Romeo lop off two cylinders from a Ferrari engine for their Giulia? According to Automation, those important design decisions are pointless, and they should have just designed a new engine instead.
Having variable cylinder count would be an amazing game mechanic. Being forced to have the same bore/stroke would mean that you would have to plan ahead. You’d have to make sure that the largest engine would fit the cars you want it to. You’d have to make sure that the bore/stroke ratio would be appropriate for all the different cars. You’d have to carefully adjust the power output for each variant. Designing a family of engines would be an incredible balancing act, and you should be allowed to reap the rewards of doing so. In real life, companies design engines with the same bore/stroke precisely so that they can build them on the same production line. If you have the skill to design an entire line of engines that can all be made in one factory, more power to you buddy.
See, I’m perfectly fine with having a fixed head type, because it doesn’t really open up new design opportunities. If head type was modular, it would just be an easy way to get more power/efficiency from the same engine line. Boring.
But modular cylinder count is the opposite. It’s not simply an easy way to make one engine better. It’s about designing new engines around a major design constraint. It’s a challenge, and one that can be rewarded with significant benefits - just as in real life.
So in summary, if modular cylinder count is nixed for the same “design decision” as modular head type, I urge you to reconsider. They are totally different game design choices - one just makes things easier, the other opens up a whole new gameplay element.
I don’t really mind if this is something that doesn’t get added to the game for a while. It’s probably not that useful in the current light campaign. But in the future, maybe after the Grand Campaign is done, perhaps with the engine designer revamp, this would be an absolutely amazing thing to have. Reward player skill and encourage creative engine design. And best of all, add a new design challenge that real world automakers actually deal with.
A link to my old topic on this subject - Engine variants with different cylinder counts
@killrob @daffyflyer