"So are you saying I can link 4 x 24v fans in series with smoke fan and they will run proportionally when the engine sounds are played"
You can link as many fans as you like to my smoke fan control box, though if they are 24V they would need to be in parallel.
By linking the fans to the sound system and not the motors, the fans in the cooling housings would rotate at a speed proportional to the engine speed, even when the tank is stationary - and lets face it, that's the only time they would be visible
And with Thomas Benedini's current Flash software, you can set the idle speed to a point just above the stalling speed of the fans, so that they can be seen spinning slowly at idle and speeding up when the engine is revved.
Adrian.