It's an Autech tuned, normally aspirated SR20 with 200HP/180WHP from the S15 Silvia (as opposed to 160HP/135WHP in the regular Silvia). Autech is an in-house tuner division of Nissan. Kind of like the original AMG. Where some projects were absolutely outside of Nissan's interest, customer demographic or capability, Autech took them and ran. You'll see their name on many of the NisMO cars because of their engine tuning.
This is the funniest comment because it always comes back to haunt us. At any angle, things are either a 15/16" fit or a 17/16" fit
It's really a testament to Spriso Motorsports and his fabrication skills.
Also, this is V.2 of the car. This setup was running for 2yrs in my Orange car before the rollover.
Here it is running a lazy tune at ~140HP a few years ago. Very fun. But finding the extra 40hp transformed the car.
https://www.instagram.com/p/Bd9dDkZAwc5/