Does upgrading differential impair car performance?

Its does not help that much.

How much do you think just the diff can improve a laptime?

For not having the pp change it does. Im not here to argue, and not everything is about laptime for me. I can care less about having a faster lap than someone, but i care about making the car more enjoyable. As far as improving the feel of a car, weather its a tail happy rwd or being able to pull a fwd out of a corner better, it def helps.

My apologies if that is how you saw my post. I didn’t think I was tearing anything apart. My main gripe is with the diff glitch myth.

The myth about a diff glitch needs to die. Firstly it is not that beneficial, not multiple seconds. Secondly it is tuning and therefore is no glitch. But the more people talk it up, inaccurately, the more people will say well if it gains that much time it must be a glitch. There is a thread on FM5 forums discussing it

The only valid way to test it is via laptimes and I am confident that going from default diff settings to well tuned diff settings will not improve laptimes, on leaderboards or online, by multiple seconds. Anyone up for a diff test?

To the OP

There is need for a differential. There is also need for throttle control.

Having reread what the poster on the other forums said I suspect they were saying that people tend to retune rather than learning how to drive well. Learning throttle control is just as much a worthy activity as is learning how to tune correctly, including diffs.

Throttle control is still needed even with the best diff setting.

You can start with a good tune, drive it poorly and lose traction, retune by lowering accel diff, regain traction but find you now have an understeering tune. A more appropriate response to the loss of traction may have been to learn throttle control.

I’ve read your OP and I may be wrong but you get those kind of comments all the time mainly from people who frown on the use of things like using ABS/TCS/braking line etc etc, those that are looking for the pure driving experience. Why hinder your own game play by taking some people’s comments as law, if your preference is to load a differential and tweak and YOU believe it makes you quicker…so be it, the more confidence you have in your car’s build the the more likely you will push it to it’s limit. Myself I always load a differential onto any car I am building (usually no cost in PI) and tweaking the differential allows me to see what/where I need to spend the remaining PI.

My lap times would be significantly worse in some cars if I could not tame the car with the help of adjustable differential, especially powerfull mid-engine cars.