I was building a rally platform for the S209 STi and decided to throw in the 2.0L F4 Rally engine and when upgrading the camshaft, I saw that it increases horsepower from 581 to 645 however it has a major drawback because it decreases the torque from 846 ft-lb to 578 ft-lb. Was wondering if yall believe this was intentional from the devs or a bug in the game.
Why use 2.0 F4 when you can use 6.2 V8?
And to your question, yes its intentional.
Well he is building a rally car, he wants a rally engine in it.
In general, some upgrades have counterintuitive effect when applied to a car, at least with comparison to previous games
It is intentional and was this way since the engine was introduced in Forza.
Without the camshaft upgrade the engine is one of the best in the game if you make use of its power and torgue peak at low rpm.
Depending on the situation it can even rival the V8 centrifugal engine. For example my '05 WRX A800 offroad build isn’t slower than the V8 one but imho more authentic and nifty. Just upshift at 5.000 rpm. The engine holds its peak power basically 100% of the time while the V8 has more power/PI but a wider variance.
Which can be a downside depending on the gear ratios.
With the camshaft upgrade it loses this unique and strong trait. Just avoid it.