I'm trying to figure out, whether there is a bubble in Tesla's stock price. Tesla's market cap is 25B, source
Tesla, Inc. (TSLA) Stock Price, News, Quote & History - Yahoo Finance
Porsche imo is a quite good comparison, because it is a small premium car sellers and also growing. Porsche's market cap is 24B, source
PORSCHE AUTOM.HLDG VZO (PAH3.DE) Stock Price, News, Quote & History - Yahoo Finance
Porsche sold 38500 cars 1Q2014, source
http://press.porsche.com/news/release.php?id=857
Tesla estimates 6400 cars sold 1Q2014, source
Tesla’s Musk Accelerating Vehicle Output Through 2014
So Porche's market cap/cars sold 1Q014 is approximately 600 000$, for Tesla the same figure is 3921875$. So 6 times bigger.
For me there seems to be a bubble.