Here is a screenshot of the flame alone and a box representing the engine. I placed a spotlight inside the box, set it's multiplier to 3 and the color to bright white. Then I attenuated the light (no decay, far start: 20 / far end: 60, but it depends on the scene) and gave it a hotspot of 124 and a falloff of 135.

Now you can non-uniformally (NU) scale it along the (here) x axis to elongate it.  In reality it's the attenuation you NU scale and you can only see it when your light is selected or set to always show attenuation.

I also added a small "core" (the dark red mesh). It was given a 100% self illuminated white diffuse colour and assigned a unique effects ID number.

The glow was achieved through a volume light with these settings.
Depending on the glow's colour, you would change the attenuation colour.
If you want it to look like the flame is streaming out, try switching on noise and applying a strong wind. By animating the phase value, you can achieve a pretty convincing jetstream.

Now to the facelifting. Add some glow using the effects ID number of the core mesh. I used the size 7 and softness 15, using a gradient with the following settings. It's important that the glow is bigger than the volume light.

   no glow
   core glow
   overall glow