Page 1 of 1

2.19:1 vs 2.61:1

Posted: Tue Nov 27, 2012 8:09 am
by Hofmanic
Hi all,

I cant really figure this out myself. I noticed that on some of the setup sheets from Bk's winning setups back in the days and also from others that he is using the gearbox of the XXT in his buggy. I kinda know how gear ratio's work's but normally you can only change your final ratio by changing your spur and pinion but since Bk used the 2.61:1 gearbox he could also change the buggy's internal ratio.

So what i cant figure out is what is the advantage of using that internal ratio? also keeping in mind that the truck wheels have a larger diameter than the buggy..

let me know what you guys think of this.. thnx

Re: 2.19:1 vs 2.61:1

Posted: Tue Nov 27, 2012 8:38 am
by jamin
Maybe he was using a very low turn motor so needed to gear it lower than normal, or maybe even so he could use larger pinions (for the same equivalent motor) and therefore move the motor further out the back of the car? I cant see any efficiency benefits by using the XXT gear, maybe someone else could suggest some ideas?

Re: 2.19:1 vs 2.61:1

Posted: Wed Nov 28, 2012 12:22 am
by THUNDERSTRIKE1
XXT IN THE XX XXCR CARS give it more punch an torque.Me i did the opposite in oval racing i put the xx trans in my xxt,that way i could hold the throttle in the turns let off it then nail it to pass everyone before the end of the straightaway.This is how i set the stock truck record,i hate usen the brakes lmao.DON

Re: 2.19:1 vs 2.61:1

Posted: Wed Nov 28, 2012 12:54 am
by Jay Dub
Jammin was close, just the wrong direction. The lower ratio trannies in the car were used to move the motor forward by using a smaller spur while still using pinions that were efficient (18t and above). The XX cars motors typically hung way out the back and made it lag in the steering department in stock form. With the higher ratio tranies, one could use small spur and pinion combinations to get motor further forward (closer to an RC10 -LOL.)

Re: 2.19:1 vs 2.61:1

Posted: Wed Nov 28, 2012 8:19 am
by Hofmanic
Thnx for the comments.

Hmmm ok its getting a little clearer :? :?

So based on the comments above with the 2.61:1 tranny you can use smaller spur and pinion to get the same ratio. That way the motor will be closer to the car and have a little more steering.

So that's a better setup for high grip tracks?

Re: 2.19:1 vs 2.61:1

Posted: Sat Dec 01, 2012 3:18 pm
by Jay Dub
Yes generally this was done on high bite, smaller indoor tracks. -Jeff