Great writeup Tony
I just joined the next groupbayfor the helix Fmic and then planning on a set of downpipes and so I should be fat and happy with my Bmw no more engine modifications
but reading through your thread got me all excited on modifing my vastgaterattelling turboīs
Could you please give us I bid more insight(driving not technical) on the difference between stage 1 and 2. Stage 2 is almost twice the price of stage 1 money well sent ??
I realy hate the way our standart turbos tapper off at high rpm, how much improvement do they offer, and how much faster does stage 1 spool up at low rpm than stage 2?
On the subject of your OCīs is It the same core(size) setrab and Ar/Setrab?