My own personal experience was tested at the circuits of the americas formula one track in austin, tx..the back straight was extremely long so in tc open mod the ball diff in the rear was very effective when set properly and the spool up front was solid and will most likely keep this combo for the next Roar tc mod race in September. .the ball diff provides a lot of bottom end and plenty of top end with minor adjustments and some maintenance can be useful in mod racing where power is paramount! !

The only disadvantaged of using a ball diff in the rear in mod racinv it has to be set pretty tight or will be destroyed like mine at the circuits of the Americas race track it was fried in two laps...

I run Reflex Racing DCJ's

Yeah, I'm totally sold on DCJs now. But I ran Schumacher Mi4's for a couple years before DCJs were available, so it was a pretty stark contrast when I finally got them.

I guess the point I was trying to make is that if you don't have DCJs, and you're considering a gear diff instead of a spool, try the DCJs.

-Mike

DCJ's all the way. You can't really describe, how much they really do, especially on a car that maybe wasn't designed originally for a spool. I ran a Mi1 last season in VTA, and with the spool, DCJ's were an absolute must. There was so much chatter from the front end it was crazy. ( This car was not originally designed for a spool...)

Ball diffs only disintegrate when you forget to goop the main bolt and nut properly... You need to let the blue loctite dry on them a bit before you insert the bolt through the diff outdrives, and after you tighten the diff all the way, you need to again add loctite to the protuding bolt threads and let that dry too... When it's all dry, you can set the diff a little tighter than where you would want it at first and run it a bit until the balls are well seated in the ring grooves, and then you tune the diff to the track... If you never use this method to loctite the diff bolt, you will always have issues... The only thing that will break the diff after gooping it like that is if you have a super powerful motor (2.5t boosted) that will pop the diff bolt's head, but no diffing out.....

ECS's are just brand named double cardan joints (DCJs). I also use the Spec-R universal shaft drives v2 ad they're every bit as good and reliable as the xray ECS. They're also less than half the price so that's really nice too.

Ive noticed my spool front end slows me down on topend even though the ratio is similar, full throttle wide turns are not as easy and my car pushes
with a ball dif it makes driving for me easier

Thankyou, at least now I now what is being said.

Or... Fill gear diff, run it. And know that you will have absolute consistency during runs between refills (9 months on one of mine)

If you want maximum available traction why not use a gear diff in the rear?

My ball diffs have over 5years on them and are still smooth... Set it and forget it....

Wow, I used to rebuild mine every three race days.