Just wondering if anyone has ever decided to keep the stock twins in their 20B swap, or does everyone just to go single for their final setup? Pretty much every 20B I've seen/heard about uses a single turbo setup, but I figured at least someone must have left in, or at least upgraded, the stock sequentials (BNR has a twin turbo upgrade for the 20B; not sure if anyone else offers one). If not, could you explain why you went for a single turbo, rather than upgraded twins? This is just for curiosity's sake.

 

I'm probably one of the few that kept the JC Cosmo turbos due to cost. Going N/A requires headers, a single turbo conversion requires a custom manifold & downpipe. Figured that if there's nothing mechanically wrong with the Cosmo Turbos, might as well put them to use. Plus, I wanted to have instant power no matter what, so the sequential twins were a no-brainer. Kinda hard to argue with hitting full boost at 1800rpm.

For these reasons, I built a new turbo control system around the twins, making them operate exactly like they would on a FD or JC Cosmo, but with a few upgrades for reliability and flexibility. Non-Sequential Override and my Boost Creep Defender System are the big ones. Please see my build thread, Project OldTree, in the FC Section for more info.

A single turbo is simpler to understand and requires only one ECU output for the wastegate. However, cost is a major factor and is covered in more detail in the 20B FAQ.