What is the different between "if it were a first class ticket" and "if he was mad he would have.."?
The difference is one of style level: "were" is here somewhat more formal than "was".
The "were" in your first example has nothing to do with past tense, but is a 'mood' form. We call it 'irrealis' indicating that it conveys varying degrees of remoteness from factuality. The irrealis mood is an untidy relic of an earlier system, and some speakers usually, if not always, use preterite "was" instead.
What is the different between "if it were a first class ticket" and "if he was mad he would have.."?
Okay, I'll explain that in more detail. Here's how it all works:
(i) "If he is mad he would...".
The "is" here is a straightforward present tense form; it refers to time, in this case the present time.
(ii) "If he was mad he would...".
(iii) "If he were mad he would ...".
In (ii) the contrast is one of modality: it presents his madness as a somewhat more remote possibility than (i) does. We refer to this "was" as a modal preterite - a use of the past tense where the meaning has to do with modality, not time.
Example (iii) shows that it is also possible to have the form "were" in place of "was" . But "was" is a tense form and this "were" is a mood form. We call it irrealis, indicating that it conveys varying degrees of remoteness from factuality.
The difference between (ii) and (iii) is one of style level: "were" is here somewhat more formal than "was".
The irrealis mood is an untidy relic of an earlier system, and some speakers usually, if not always, use preterite "was" instead.
