Tfrasca
Active member
- Joined
- Apr 20, 2015
- Location
- Ben Lomond, CA
I am building a 16v B230 with a BW s252 (I have a 1.00 twinscroll housing, but may want to use a .85 instead). My thought is that I want it to flow enough to make decent power at around 8k rpm. Not super concerned with peak power, but I'm assuming the 350 whp range.
I realize that a 3" down pipe would be fine for this, but I'm wondering if I stand to gain anything by using a 4" one. Better spool characteristics, and more flow at high rpm? I will be dumping the two 38mm waste gates back into the down pipe.
It would obviously be a tighter fit with the 4" tube, but I already have a 4" v-band for the housing, which is what started me down this road.
Thoughts?
I realize that a 3" down pipe would be fine for this, but I'm wondering if I stand to gain anything by using a 4" one. Better spool characteristics, and more flow at high rpm? I will be dumping the two 38mm waste gates back into the down pipe.
It would obviously be a tighter fit with the 4" tube, but I already have a 4" v-band for the housing, which is what started me down this road.
Thoughts?