My next trick... A Helo soundpack for a 'Flying Flapjack' with electric motors!

Im going to see if I can do this successfully... I want to make a soundpack for my 'flying saucer' looking lifting body plane. The thing has 8.4 feet diameter monster props and 400 BHP Tesla automobile motors (2). So the Bell helo sound is perfect. Whirring for the motors and 'whopping' for the fans. Now to detune the whirring a bit, and maybe increase the whopping a bit.