I noticed TT vs Positive Displacement vs Centrifugal superchargers make about a 10 Pi difference with TT leading. Why is this? Wouldn’t superchargers be better because no lag? I’m not new to Forza but new to cars in general so I don’t know a lot. Only thing I can think of is the weight , superchargers weigh about 70 lbs heavier than TT. Any input is appreciated thanks.
Turbochargers work by using exhaust gasses to spin a turbine, while superchargers work by connecting a pulley to the crankshaft.
In Forza you usually have two options for turbochargers: twin turbochargers or a single turbo. Sometimes the twin turbos make more power, sometimes they make the same power. When they’re the latter and the option to use a single turbo is an option, then I usually go twin turbo since there’s less lag (since it’s two smaller turbos than one large turbo). That’s another thing I forgot to mention, lag. Turbochargers have to spool up first, so there’s a period in the lower RPM range where the turbo doesn’t supply power, so adjust your driving style accordingly.
The other style of forced induction is superchargers. Positive displacement superchargers add power throughout the RPM range equally, while boost from centrifugal superchargers increase in relation to RPM. Superchargers are my favorite mainly because they have no lag since they’re directly connected to the crankshaft. Positive-displacement superchargers are good for adding power in general, while centrifugal superchargers can increase high-RPM power, which is why they can give a fairly decent power increase in conjunction with camshaft upgrades.
1 Like
Boost lag is so minimal in all but a few cars (Peugeot 205 FE), I don’t notice it. Front-engine builds get turbos (less weight off the drive wheels). Mid/rear-engine builds often get positive-displacement superchargers for more weight over the drive wheels. Certain engines I’ll put centrifugal superchargers on. It depends on the base power band, stock transmission (or if It has a race transmission), and class. I think A class cars are most likely to benefit from the cenitrfugal’s torque concentrated at the top. S1/S2 cars especially in PVP where versatility is paramount I imagine are better with positive-displacement, and most of the engines in those cars already have peaky power. The Ford GT '05 (S1) has a great power band. I don’t remember if it can take the centrifugal or not. If it can, that’s one that would surely be faster (the stock gearbox is good too).
Turbos work off exhaust gases. Superchargers work off a belt and pulley. A TT is more efficient, and you get full boost faster. A SC feels more like a naturally aspirated engine, and you get more boost at higher rpms, as the engine turns faster, your sc turns faster. So, imo a TT is better for the road, and a SC is better offroad. For rally, it depends more on whether it’s a scramble or trail. I have a TT on my circuit car and a v8 sc for my trail car. The reasoning being that in circuit racing and road/street, launch is more important than top end boost, but in cross country and rally trails, l prefer getting a top end boost for hills, and l prefer the more natural feel of an SC boost. I’m probably in the minority, but if l had to choose, l’d pick the SC. Imo at low rpm, you’re running off mainly torque, and some hp, so boosting here is kinda overkill. I’d rather have the majority of my boost coming at the top end when my torque curve’s already fallen off. And again, l like the feel of a SC. Not to mention, if your differential is off, a SC is more forgiving, where a TT will have you spinning tires for days. Hope this helps. The info is accurate, but the preference is purely opinion.