What is the fine-grained topic of the following text: The 340R tank has a curved fuel filler inlet pipe rather than the straight pipe seen on the S1 Elise Exige and there are two variations in the S1 Elise Exige tank which can be identified from looking within the engine bay on the right hand side of the vehicle, where the fuel filler is located. Only return the topic.
Fuel tank specifications of the 340R and S1 Elise Exige vehicles