Ok so I've been using this site **broken link removed** to do the math for me.
Just please let me know if this is gonna blow up on me or not, just type these numbers into the site listed above.
12 Source voltage
2.4 diode forward voltage
700 diode forward current (mA)
100 number of LEDs in your array
PLUS
12 Source voltage
3.8 diode forward voltage
700 diode forward current (mA)
20 number of LEDs in your array
RUNNING off of a 12V 30A regulated power supply
So is this a failure or success?
That calculator is seriously flawed. It often works, but in some cases it does not. In the first set, with the 100 off 2.4 V LEDs it is wrong.
The calculator has two problems. The main problem is that it does not have any minimum voltage difference between the LED voltages and the supply voltage. The smaller the difference between the supply voltage and the LED voltages, the worse the current control will be. You cannot take chances with 700mA LEDs.
Secondly, the calculator will not give a value less than 1 Ω. In fact, if it calculates less than about 5 Ω, it is probably time to find another solution, but there is no warning about that.
The problem you will get is that small variations in voltage will give large variations in LED current. With a total of around 20 A flowing, you will get small variations in voltage due to voltage drop in the wires.
You would be far, far better to use an active current control circuit for each string of LEDs.
Something like the circuit in
**broken link removed** but with a smaller value resistor, a larger transistor, and a heatsink, would be a start.