Everybody's a critic- I like Nate_Mans best because the flame is separated visually from the X more. But on his, the top right corner of the X is longer. Is it part of the letter? The other 3 corners are not long they clearly stop as in a traditional font. The length implies it's the flame, but it's not that either. I made a design for Tee Shirts where the fire/flames are coming off of the letters:



Consider my input after understanding what I did, I may be way off.

I really like the black/red combo, but our car is Yellow, not going to work. We have Andrews emblems and are happy with them, but your designs are fresh, new and sharp. Another thing is the respect you showed Andrew, well worth noting. So........
flames-yes
new without the coupe/roadster image-yes
original art-yes
two tone silver combo-doesn't do much for me
Could you work it so that it's black and the color of each car? That would really play off of the color well. Black cars would then have black/silver combo:


Now black and red work well with a yellow car!