Any tips for what upgrade parts to prioritize after handling upgrades?

Need some advice on the more important upgrades to shoot for after taking care of handling updates like suspension and wheels whatever else I could fit into a smaller Pi budget. Lately I’ve been enjoying racing lower classed races and enjoy the slower pace for a min and usually whatever car I go with doesn’t have much room to work with to stay in a certain class. But more specifically it’s mainly power upgrades that I spend way too long on but besides the time I’m burning up splitting those hairs lol also can’t help feeling I’m reading into the numbers a little too much since I’m not a huge forza player and usually just auto upgrade or use someone else tune which I’m trying to break that habit hopefully. Also I’m sure similar question aren’t a rarity around here so forgive me for posting another but I tried to be somewhat specific at least. Feel free to leave any and all advice or a link to a thread that I’m sure already exist but I didn’t see one in the short search I did before posting. Lol thanks

I don’t think this question has a right answer.

Due to the rather obtuse way that Forza assigns PI to upgrade parts I have found that, well I can’t find any general rule I can apply :- other than noting that

  1. in the Engine category there are a generally a lot of options, which in turn makes a search space grow exponentially. An Engine with 4 “Race” upgrades only has 16 combinations to consider. With 8 Race upgrades, you’re up to 256 combos. Give a few of those selections, Sport, or Street variants and you’re looking at 1024 or more combinations to cycle through.
  2. Changing the Camshaft changes the relative value of everything :- Most other upgrades are independent: Changing the engine displacement doesn’t effect and hp bonus, or PI cost of a exhaust or Turbo upgrade.
  3. For engines where the number of combinations has been small enough, I’ve managed to tease out a few more kW than the meta-tunes by simply going though each combo and putting the results in a spreadsheet. I find that there are generally some surprises when you combine some mid tier parts :- basically theres a PI premium on “Race” parts, , but spreading that PI across two sport components can sometimes yield a greater overall benefit. Sometimes. This is not common, most combos do not show this :- you must search for it.

Consequently my general rule is simply this: when evaluating engine upgrade pieces, just look at them in isolation: and see

  • does the upgrade add or remove weight. If it removes weight, I like it.
  • According to the performance calculator does the upgrade improve, just speed, speed and handling, or a whole bunch of car performance metrics: I like upgrades that show more green numbers. I prefer upgrades that improve handling and braking, and I prefer upgrades that don’t just make the numbers green, but show a visible improvement.

I don’t believe spark plugs give you anything different than valves, etc.
But, air filter and exhaust reduce weight the most and help with too much front weight bias. Whereas oil and trans coolers add weight and usually on the front end.
A supercharger’s benefit is low end torque, useful sometimes for high revving, low torque engines if you need help launching or coming out of corners.
The turbos’ benefit is more torque, but having it come on higher and stronger in the rev range and benefiting top end vs launch/corner exit.
The centrifugal supercharger adds HP at higher rpms and raises the rpm range and is the lightest option, useful for more speed per gear and when the low end already has ‘too much’ torque/HP.

I completely forgot I post this, my apologies. But yeah the combination possibilities were getting to me lol. I learned to essentially judge based on all those things more quickly and efficiently in the mean time at least lol. Still come across some cars where there will be some odd ball parts that have weird pi properties tho. In which case I just pick what I would want on my car in reality and let it go at that. Lol I hope for the next horizon game they develop a more fluid and transparent system for seeing how things will affect your cars performance. I’ve realized how inaccurate the performance calculator can be. Sometimes you can go back and forth between 2 gear ratios or whatever really, and the 0-60 & 0-100 times for the same gear with sometimes randomly be a different value then the other 10 times you checked it which doesn’t make it any easier to fully trust it. And there’s been a few instances where I make a couple tunes for the same car for testing and the worse looking tune based on the calculator for top speed or something easy to test, with out perform the “ better on paper” ones. Uncommon but I’ve had it happen more than once. But yeah I started keeping a notebook on hand when tuning just so it felt a little less like just guess work and I’ll definitely agree that’s there are some interesting combos out there if you got the time and patience to dig for them. But other than rivals you’ll probably never get to put them to they’re fullest potential unfortunately. Maybe in the next one hopefully :joy: