Why can engine variants stroke only be smaller?

[Tycondero]

I was wondering why is it that the bore and especially the stroke of new variant of an engine can only be made smaller. I thought we were allowed to at least mess around with the stroke. Shouldn't we be allowed to increase at least the stroke with a new variant to a minor extend? Otherwise this means you always need to build the most expensive/largest version before and downscale for the other variants. I understand we should not be allowed to go from a 2l engine up to 4l or so, but increasing the cylinder capacity by increasing the stroke up to 10-15% should be possible with new variants I think.

[Killrob]

You basically explained it perfectly yourself already!

If you could make it larger in the variant, then that would ALWAYS be the optimal way to do it, giving you larger capacity for the same engine size and weight. So that would imbalance the game a lot. The only solution is to have it like you say: maximum size has to be built first, you can make it smaller in the variant later. Then you would ask: so why not make a new family for every engine then? Answer: no good reason for that now, but in the tycoon part, you'll be able to produce all engines from the same family on the same production line, giving you a big advantage in tooling costs and overhead costs.

Cheers!

[Tycondero]

You basically explained it perfectly yourself already!

If you could make it larger in the variant, then that would ALWAYS be the optimal way to do it, giving you larger capacity for the same engine size and weight. So that would imbalance the game a lot. The only solution is to have it like you say: maximum size has to be built first, you can make it smaller in the variant later. Then you would ask: so why not make a new family for every engine then? Answer: no good reason for that now, but in the tycoon part, you'll be able to produce all engines from the same family on the same production line, giving you a big advantage in tooling costs and overhead costs.

Cheers!

Ok, thanks Killrob for explaining this. So, in the tycoon part would this would then kind of mean that you should design a relatively big engine with the very best stuff (prototype model) and downscale cylinder size for different cars that do not need to have the top of the line engine?

[Killrob]

Only the first tab is locked once you have more variants, so you can still "go for the best stuff" with individual variants, but the valvetrain setup and the block needs to be shared with all variants So yeah, you need to think: how big do I want to go with this family? Then you choose your maximum size and downscale the other variants from there.

Cheers!