FAILURE -------------- the way I see this right now is that a brake dyno is no good for a CVT drive.
You must run an inertia dyno. No chance in hell a brake dyno will work without doing damage. JMHO.
At this point I think I will have to kill this project but I did get some baseline data that I will share here.
Data, please bear with me while I explain the numbers.
I managed to pull 3 data points that were useful. The rest were junk because of glare from the shop lights on the
Engine rpm gauge, vibration of the rig causing unreadable torque readings, smoke in the shop from the burning belt.
Torque 171 ft/lbs at 6780 Engine rpm at 377.5 axle rpm
Torque 204.4 ft/lbs at 6740 Engine rpm at 339.3 axle rpm
Torque 231.5 ft/lbs at 4800 Engine rpm at 278 axle rpm
First line: 30.7 HP
Second line: 33.01 HP
Third line: 30.63 HP
What does all this mean and how did I come up with the HP number.
1) My brake dyno has a torque arm that is 2'6" from the shaft to the load cell. So this means you multiply the torque by 2.5
2) So now you figure out HP of the Engine --- the formula is rpm x torque divided by 5252
So lets take line one for an example:
A) 171 ft/lbs x 2.5 torque arm is 427.5 ft/lbs of torque on the oddy. (I can hear you guys laughing so just sit there and have another beer while I explain it later in this piece)
B) Axel rpm 377.5 x 427.5 ft/lbs torque divided by 5252 is 30.7 HP
CVT ratio: Axel rpm must be multiplied by 10 to make up for the 10/1 gearbox ratio and then you take the Engine rpm and divide it by the updated axel rpm to get a CVT ratio.
Axel rpm 377.5 x 10 (gearbox ratio) equals 3775 rpm. Engine rpm 6780 divided by 3775 is 1.79 CVT ratio.
So the total gear reduction at this particular point in the test was 10 x 1.79 = 17.9/1 total reduction.
This is the reason the oddy has such incredible torque but it's also the reason an oddy will only do 63 mph.
A corvette will do 150 mph because the gear ratio is real low (3.9/1 or 4.11/1) and it has 500 HP to keep it there. If you put a transmission in it with 17.9/1 reduction it ain't gona do 150 mph anymore but with 500 HP it would be able to rip anything apart. That's how this all works.
Here is a good read that explains what I just said but you have to read all of it to understand it:
https://tech.corvettecentral.com/2015/1 ... formation/CO
Edit: Based on what I see here the Torque/Hp magic number is 6700 rpm for this Engine.
Edit again: If someone see's something wrong with the math (Adnoh ?) feel free to shoot at me.
CO