Why flip the tranny?

[ynmech]

I have seen a lot of aftermarket options for doing this, but what are the benefits? I know that with the original tranny it was for a dig to work on the rear, then it was to get some of the roll-out of the chassis. Just asking...

[IVIaarten]

I guess scale looks, and making room for a full interior if you want to. Maybe also to put more weight on the front axle (not really needed imo). Will probably negatively affect performance (higher CoG).

[WesleyRoy]

I tought it is to help prevent torque twist.

[1967Typhoon]

The main benefit is more weight in the front. The second would be slightly more room for an interior, if you chose to go that route. The negatives are slightly more weight on one side (battery and motor are now on the same side) and having to mod the battery tray and receiver box. There are vendors on here with products to fix those issues though.

I debated back and forth about flipping the trans, but in the end I am keeping it as-is. I really like the balance of the chassis. It is very neutral. I have the weight exactly where I want it now, and I am betting that if I flipped my trans that I would have TOO much weight up front. Too much up front can make decending down steep hills problematic. The truck can want to tip and roll forward.

[IVIaarten]

Originally Posted by WesleyRoy

I tought it is to help prevent torque twist.

I think that was only the case for the original SCX10 transmission, and doesn't apply to the 10.2 kit transmission.

[QuesoDelDiablo]

From what I understand, flipping the tranny in this rig is purely an aesthetic maneuver. As it sits, the bell housing faces the wrong direction and that bugs some people who are looking for more scale realism.

And just to clarify, flipping the tranny was more commonly done on the orig SCX, but it was actually the mirroring of it and not the flip that helped reduce torque twist.

[Kapti]

Getting less torque twist is only possible in one way.

Reduce effective torque. You can achieve this in two ways

Lower the power needed to move the vehicle.
Change the gearing in the rear axle to a lower ratio. In doing so you reduce the torque needed to move the vehicle. Or lighten the vehicle.

Change link geometry to better resist the opposing forces.

If you dont change one of those, your not doing anything.

As long as you have one body providing torque to another detached body it doesnt matter how you flip, roll, reverse, mirror, angle the motor. It is not the one causing the problem (not directly anyway). Yes you can add weight to one side of the vehicle and it will not twist as much under accel. But under deceleration it will be worse, so that is why it is not included(your not canceling anything).

Sent from my SM-N920P using Tapatalk

[1967Typhoon]

I appreciate the insight on torque twist....but are you saying that mirroring the old transmission shouldn't reduce torque twist? Because just making that one change completely eliminated torque twist on my first SCX10.

[IVIaarten]

Have to dig deep in my brain cavity for the stuff I learned long ago, but torque is torque. Flipping or mirroring a transmission will not reduce the torque it generates. What might help diminish the effects of this torque is changing the position it's applied from (for instance on the right side it might try to twist the right downwards (the torque twist), while on the left side it would try to lift the left side up. The some moment (torque), but applied with or against gravity, reducing or increasing the effect it has on a vehicle. Also moving the 'center of torque' closer to the center of the car will reduce the twist resulting from it (shorter arm). At least, that's how I remember it

edit: or maybe two sources applying torque in the same direction (amplifying the effect) or in different directions (partly cancelling each other out).

[EeePee]

Since I'm the guy that first posted about mirroring a transmission I can add this; it adds weight to the side that lifted. That is the point. It's not like people corner weight these trucks, so it's as easy as just put more weight on the side that lifts. It worked.

[ynmech]

Thanks for the info!!

[svt923]

There are a few other points to the flipped transmission that haven't been mentioned:

1. The stock truck was designed to be balanced with a full size battery pack. Most people have moved to smaller packs so you may end up with a rear weight bias depending on how much smaller of a pack you run. A small 3S will take 6+ oz off the front end vs the 5000mah 3S packs that some of the Axial guys run. My truck measures at about 58:42 weight distribution after flipping the trans with a 2200mah 3S pack.
2. The flipped transmission will let you run a Honcho body (or similar cab style) and cage without cutting up the cab back for gear cover clearance.
3. The front no longer requires the super short front driveshaft after the flip, easier to share parts if you have other trucks running the Wild Boar HD shafts.

[Col_Sanders]

With the kit transmission flipped around it looks more scale, helps with room for interiors, and moves the weight forward. More weight up front helps with climbing.