Not a realism addition, more a balancing one.
Due to rather drastic changes of PI scalling in FH5 many classic cars can no longer be competetive without conversions, some won’t even reach top of popular classes unless you add unneeded upgrades. For example 302 Boss, Toyota MR2, or newly added Abarth 124 can’t reach top of A class without giving them completely unneeded racing tires. Some cars can no longer reach even B class, which is the lowest class for MP.
Rather than re-evaluate all upgrades for better fit with new PI scale, which would be way too much work and mess with existing builds, what I propose is additional upgrade module that simply increases engine’s performance at price of appriopriate PI increase, to allow car to reach competetive levels of power, while retaining its original sound. Let’s call it High Octane / Performance / Racing fuel, just to go along with general theme of Forza upgrade system.
I like the idea, but I’m confused over why racing tires are “unneeded”? Vintage factory compound tires are single-handily some of the biggest reasons old cars were so slow compared to their newer counterparts. Throwing some Michelin Sport Cups on a top-spec 60s Muscle car in real life would likely allow it (other than during braking) to hold up with their modern equivalents. Old tire technology was frankly terrible compared to today’s.
Well, I’m talking gameplay wise, not real life. Racing tires are often not worth PI cost in A class, unless you specifically intend to create grip build.
That’s just bandaid for one of balancing issues brought with new PI scale, that was stretched to accomodate for cars that in older games would be too powerful even for S2 class. In hindsight, Playground should have just make S3, but that ship sailed away 2 years ago