All speed runners

[wadedog]

I’m thinking about using limitless v2 diff gears in my stretched typhon 1721 xlx2.or should I just leave the stock gearing in

 

[Moirae]

The limitless v2 gears will definitely increase your top speed

 

[LicketySplit]

Not needed unless you’re running out of adjustment for lower gear ratios. That being said, let’s say you’re geared for 100mph with both setups. Your center drive train will spin slower putting less wear on things.

 

[RedondoBeachRC]

There are some factors to consider such as gearing options, top speed youre trying to reach, and length of road youre going to run on. A 3.3 would be easier on the the electronic components whereas the 2.8 would add more load on the same pinion/spool gearing. But the 2.8 would spin at a slower rotation, so less wear on the drivetrain, possibly. The 1721 takes awhile to get it RPMs up and 3.3 would make it that easier.

Its all very situation dependent

 

[Diem Turner]

The 3.3 diffs are easily good for 150mph+. If you're not planning on taking it beyond 160-170mph and you have access to the full spectrum of pinion/spool gears, there's really no pressing reason to swap out the diff gearing. Yes, there's the lone factor of lowering the rotational speed of your center driveline that has already been mentioned, but to address that I would first go the route of upgrading your center drive shafts with high quality CF or Ti shafts to eliminate vibrations. And while this is only a superficial/aesthetic benefit of the 3.3 diffs, they do sound cooler than the 2.8 gearing. They have a definite F1 vibe going on. But that's just me.