Dual-Head extruder ready for print... Cooling problem

Upgrading my reprap i've chose that extruder

I'm trying to use it with ramps 1.4 and marlin firmware but now i have to solve an issue... Trying to print with abs i can't reach temperature over 208°C with extruder fans on (and also gain 200° requires a lot of time), without fan i've reached higly temperature rapidly but i think that it's not really safe... Anyone have experience with that extruder?
How can i add fan support on raps with already 2 hotend and heatbed?
What I have to change in marlin to have slow fan speed during heating (and printing) but high if over-termperature or print-end?
Could be a solution mantaining costantly fan on but at slow speed?

Thanks

1. You don't have enough supply current (amps) from your extruder power supply
to heat and keep hot your hotend ?? got right voltage ?? 12 / 24v hot end?
?Can you power One hotend OK?
2. Do some temperature measurements to find out where the heat is going?
.........The aluminium plates above hotend probably sucking all the heat out of hotend putting it in extruder/motor
......... You only want to heat hotend and isolate it from other parts
.............I used similar mBot mk 7 and the mounting plate was steel -- much less heat conductive


Keep the HOT .... HOT and the COOL ... COOL with good isolation / insulation between

Can anyone please tell me the firmware for Dual head exttruder??

can you please suggest me firmware for dual head extruder

Both Marlin and Repetier firmware handle dual extruders

Marlin
[github.com]

Repetier
[www.repetier.com]

has a configuration tool

[www.repetier.com]

Solved, for anyone that has similiar problem, that's the solution:
On Extruder specs is listed that the distance between fan top and nozzle bottom must be 80mm, but measuring the mechanical diagram i've seen that the nozzle showed has an height of about 6mm and the real nozzle is about 10mm... So the correct distance between fan top e nozzle bottom became (in my case) 80-6+10= 84mm...

Explanation: Setting distance to 80mm (as in mechanical drawing) my hotend top was costantly cooled from fan (about 4mm of hotend were exposed to fan) and causes cooling of the entire hotend, Setting it to 84mm reduces the exposed (to fan) hotend at about 1mm, and i can reach every temperature in short time, cold parts are cold and hot are hot... cooling with heating powered off is a little slower but i can go from 260° to 21° in less than 2 minutes...

Important notes: Reducing the exposed (to fan) hotend lenght, increases the distance between hotend top and extruder gear, and if the distance is too high the filament doesn't go into the hotend.... So you have to (probably) make some tries increasing or decreasing distance (i think 1mm of range is reasonable)

Important notes2: During tests i've seen that the difference between temperature readings (with thermistor or thermocuple of the hotend) is about 5° less than the internal hotend temperature (measured with a thermocouple inserted in the hotend) during heating.. So, set your desidered temperature considering that..