So other than the obvious 40HP, are the differences in R-Sport and S trim, mostly trim/cosmetic?

Is the 40 hp increase all tuning? I can see by just replacing intakes, installing smaller pulley and bolt on exhaust the 40 hp can be added.

Mostly curious. But interested to start a build. XF is a pretty unique car in my area, so potential for a unique build is high.

 

My understanding is the extra hp comes strictly from tuning, no special parts needed. My only concern with a build adding a lot of hp would be the split crankshaft..... haven't heard/read about a failure but split cranks are rare in motors (not unique to the 35t though).

 

Hi,

the 40 hp difference between R and S trims is purely in the programming. VelocityAP and Eurotoys (as well as a few others) will take both models to 410-415 hp with just a tune flashed through the OBD port or over 445 hp (and a lot of extra mid range) when combined with a bigger crank pulley (and a new drive belt). The V6 already has a small diameter supercharger pulley, and changing it therefore yields just a few psi's of boost. Intakes and exhaust mods are much more for sound than for actual performance increases. The tune will add quite a bit of supercharger sound because it keeps the bypass valve inside the supercharger closed at WOT to maximize boost. In my experience it adds more sound than removing the engine cover, sound deadening liner under the hood, and replacing the original airfilters with aftermarket ones.

 

Thanks for the information. I wonder why it is de-tuned so much. You would think they would want to be competitive as possible in the 'Sporty Sedan' segment.

Makes me wonder if the rest of the drivetrain can hold it, or if the ZF transmission had issues at that level.

 

They are.

 

For 2018, only the S comes with the 6 cylinder supercharged engine. Everything else is a 4.