I almost posted this suggestion the other day, talked myself out of it but then watched the new dev video released today discussing what is to come with 4.3 and decided it would be worth posting.
I see that the team is getting ready to release a whole mess of engine designer improvements and changes, and I very much love it. New block materials, new forced induction systems, overboring, etc. But there is something that I would like to see changed in the future: separating ignition and fuel systems.
I know from searching the forum that this has been presented/suggested in the past, and at those times it was rejected because either the engine designer was feature locked for the time being or the devs felt that this was too much nerdy-ness or realism to be fun. But, considering they are revamping the engine stress calculations on crankshafts to account for connector rod+piston mass, and connecting rod stress based on piston mass, and that they are going to be giving us MUCH greater control over things like gear ratios in the drivetrain when creating cars, I think this is a good time to suggest.
Currently, the ignition system technology is part of the fuel delivery system and there is only really 2 ignition systems: distributors (grouped with ALL fuel systems except direct injection) and Coil on Plug (grouped only with direct injection). But there is a lot more to ignition system history than this that they could explore.
Just in terms of evolution of ignition system technology starting around 1946 you have:
1946 till ~1970: Distributors using points and condensers (and oil filled ignition coils), basic, rudimentary technology, got the job done but not very accurate, often had reliability issues and required maintenance (gapping the points and such)
Around 1970 you see the introduction of electronic ignition distributors, eliminating the points system. This was also when most manufacturers started using air core ignition coils which could reliably delivery a hotter spark. Examples of this are GM HEI, Ford Duraspark, Chrysler “Orange Box”, and Nissan “Matchbox” (although Chrysler and Nissan used oil filled coils for their early systems). The advantages here would be things like slightly more power, better reliability (these systems required far less maintenance than points distributor systems).
The next advancement was coil pack and wasted spark ignition. This would be a substantial engine reliability increase as these systems eliminated the distributor completely. Engine maintenance score would also improve as there are fewer moving parts and no cap/rotor to replace. some power gains might be seen but wasted spark systems still use 1 coil to fire multiple spark plugs, so spark energy is split among multiple plugs/cylinders (this is nerdy explanation to justify stat changes).
The next advancement would be coil near plug (think LS engines), coil on plug (pretty much everyone else) and sequential ignition. This is probably the most substantial improvement in ignition technology as now each spark plug/cylinder has it’s own coil to generate spark energy. Coils have more time to charge before being discharged. In terms of stats, this would be yet another increase in engine reliability but also a decent increase in engine power/performance. This technology has been around and in widespread use alongside multi-port injection systems long before direct injection.
So now fuel systems. To be honest there isn’t a whole lot for me to expand upon, the team has a pretty darn good spread of fuel systems between carburetor options and injection systems.
I could see them adding more specific stepping stones in the fuel injection systems, like:
Batch fire injection (which visually looks like multi-port but fires more than one injector at a time even when a cylinder isn’t ready for fuel). This system wouldn’t really have great fuel economy but it is better than single point injection (“throttle body” injection). Examples of this in the real world are any vehicle that ever used the Bosch L-Jetronic injection system (including licensed copies like Nissan used extensively on their 75-83 Z-cars). Batch fire also isn’t all that great for emissions due to the aforementioned unnecessary additional fuel spray but it is still better than carburetors and was used alongside catalytic converters.
I’m not asking for full on ignition and fuel tables that users can tweak like one might when tuning a car in real life using an ECU, any of these systems can be rationalized by stat changes like they already do with the existing options in the engine designer.