Is there a possibility Automation will be updated to allow larger engines?
The 120x120mm bore/stroke limit makes developing landyacht engines which have a very long stroke to make a 8+ liter engine fit in the bay.
If not, is it possible to mod the game to achieve this?
No, Automation will not allow for more than 21.6L engines (using a V16) because they are not practical and were never really used in automobiles. Only a single production car did have a 10+L engine after WWII I think I remember from our research, so the current limits are more than generous. Modding of these limits might work, but the calculations are not optimized for that.
GMC pickup/light truck engines had at the largest sizes a bore of 5.125" (130,175mm).
The Hispano-Suiza Tipo 21 had a 6i with 11l of capacity; or the Fiat Mefistofele, with an plane engine Fiat A.12 6, had 21706cc of capacity with 320hp, and BMW Brutus, with an V12 engine with 47000cc of capacity and 750hp
After the II World War, the Jay Leno Tank car (2003) had a 29333 cc of engine capacity; the 2003 Cadillac Sixteen Concept (13600cc).
[quote]The Hispano-Suiza Tipo 21 had a 6i with 11l of capacity; or the Fiat Mefistofele, with an plane engine Fiat A.12 6, had 21706cc of capacity with 320hp, and BMW Brutus, with an V12 engine with 47000cc of capacity and 750hp
After the II World War, the Jay Leno Tank car (2003) had a 29333 cc of engine capacity; the 2003 Cadillac Sixteen Concept (13600cc).[/quote]
And these are all mass-produced cars/engines for general use in automotive industry? 
I would like to be able to create a car with Wartsila-Sulzer RTA96-C marine diesel in it. Would this be possible? Total displacement for 14-cylinder model is 25480 litres and each cylinder produces 7780 horsepower. 
You might also need to create some bigger car body for this. 
Guys, you need to talk to this guy and his Renault(?).
[quote=“adamd”]Guys, you need to talk to this guy and his Renault(?).
[/quote]
Haha. 
But I was thinking more something like this:
Haha.
But I was thinking more something like this:
[attachment=0]image.jpg[/attachment][/quote]
Stop asking for diesels for fuck’s sake! 
[quote=“NormanVauxhall”]
Stop asking for diesels for fuck’s sake! 
[/quote]
Lol! But this was more about just larger engines. 
An engine that huge and being petrol … O.O
To answer your question: nope. Engines size limits stay the same. Engine designer will not change anyway and it’s pretty much at a very good point gameplay wise.
And for every suggestion or complain the release of the game gets delayed by an unspecified amount of time X-P
