I know you guys will hate people like me who ask dumb questions but since I'm a noob on 7s (just got one 2 months ago) I'm just curious on what the difference between a non-sequential and a sequential turbo is? Please explain to the young grasshopper!

 

This has to be talking about twins

Non-seq=Both boosting at the same time.
Seq=One turbo at lower rpms, one turbo at upper rpms.

 

Sequential setups include two turbos. One does all the work down low, then a second one comes online with the first for the rest of the rpm range.

 

Thank you so much guys, now my other question is some guy is interested on selling his non-sequential stock twins, exactly how reliable is this? Isn't it better off having a single turbo conversion then?

 

I personally prefered non-sequentials over the sequentials but everyone is different. Depending on what you're goals are with the car, yes a single turbo setup is better, but it also costs more and you need more mods to support it. Fuel, engine management, etc, etc....