RC-Monster Forums - View Single Post

BrianG · 07.09.2009, 07:05 PM

I'm not sure how the power would scale up, but the power:weight ratio seems reasonable.

For instance, take an 8th scale vahicle weighing 8lbs fully loaded with 1200w peak power. 1200w/8lbs=150w/lb. If a given 1:1 car weighs 3000lb, that's 450,000w, or 600HP.

Seems "low" until you remember torque is much higher in electric.

OK, most performance 1:1 cars can do around 150mph. That would be a 8th scale buggy geared for ~53mph. If I assume 100A draw (for max torque) on a 4s buggy with a Neu 1512/2.5d (fairly typical setup) I get 2.49ft-lbs of torque geared for that 53mph. That is a .311:1 ratio. On the same 3000lb car, that's 933ft-lbs of torque.

I'm sure it's more complicated than this, but it seems reasonable...

	(#11)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	07.09.2009, 07:05 PM I'm not sure how the power would scale up, but the power:weight ratio seems reasonable. For instance, take an 8th scale vahicle weighing 8lbs fully loaded with 1200w peak power. 1200w/8lbs=150w/lb. If a given 1:1 car weighs 3000lb, that's 450,000w, or 600HP. Seems "low" until you remember torque is much higher in electric. OK, most performance 1:1 cars can do around 150mph. That would be a 8th scale buggy geared for ~53mph. If I assume 100A draw (for max torque) on a 4s buggy with a Neu 1512/2.5d (fairly typical setup) I get 2.49ft-lbs of torque geared for that 53mph. That is a .311:1 ratio. On the same 3000lb car, that's 933ft-lbs of torque. I'm sure it's more complicated than this, but it seems reasonable...