what can i do now Ramps/Arduino quuesion?

Sounds about right. In reality, the needed torque is difficult to calculate precisely, so the easy way forward is to assemble the machine and adjust the current till it runs properly. The motors you have are known to be suitable for reprap, you have standard stepper drivers, theres no real need to worry about what exact current setting to use.

i know its just going to be plug them in adjust the trimpot but what i was original asking I am going to take this down to simple terms for me to be able to put across what I am trying to do when the motors arrive, right i plug my steppers in making sure the trimpot set low ( motors probably won't move) now I would adjust the trimpot till I get the motors to turn, now im stuck from here onwards and these are the questions I am after.

1. As my above post as a Rough calculation i need to make the motor run 27.7% + taking on the fact of temperature rises as i want them to run and cool as possible so knowing that say for instance i want to round the 27.7% to 30% for easier purposes i just apply the same 30% rule to the voltage and amps as my steppers are rated at 3.1V so 3.1v*0.3=0.93v and amps are rated at 2.5a so 2.5A*0.3=0.75A now i used the calculator online with the 1.250 ohms set and it gives me same result so i gather am I correct ?

2. And if so Now where do i point the probes to checks all above.

You should always use the highest torque you can get for best accuracy and acceleration. That means use the highest current that doesn't overheat the motors or the driver.

If you run the motor at 27.73 percent of its rated current, then yes you will get 13.7 N-cm but don't forget to multiply by 1.4 to account for the fact the motor rating is 2 coils on and the Allegro formula is peak current in one coil. So that works out at about 1A on a 2.5A motor.

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The 0.93v is a meaningless figure. The current is a little lower than I would use, bu the corrsesponding value for Vref is 0.3v, measure that between the trimpot wiper and ground.

ok where do i measure then once plugged in, makinging sure im supplying the 1A and this will prob see the end of my questions lol

Stick the black probe on anything marked GND. The negative side of the main power terminal is a good one, the screws are connected to the wire so just poke it in.

Stick the red probe on the screw of the trimpot.

That value is Vref.

ok ty

because i have 5 drivers and only 2 are which for the extruder instead of using the 2 on Z i Can put one on E1 and one on Z, would there be any benifit from doing so?