BNR S4, One heck of a turbo!

[Redline]

There are some people who prefer the power band of the S4 and are okay not going past 450whp. But most people who are going to get an S4 are probably not planning on building any time soon. It is the new perfect stock block turbo.

I basically say the same thing about my S3 (perfect for stock block). I'm at ~380whp (with ethanol, of course) and the powerband/responsiveness is awesome. Spool is almost as quick as a K04, yet I have 50-60 more whp up top. It'd be interesting to drive an S4-equipped car back to back with mine. I'll bet it's a little less responsive, yet climbs in the upper rpms even more.

 

[EdgeAutosport.com]

I basically say the same thing about my S3 (perfect for stock block). I'm at ~380whp (with ethanol, of course) and the powerband/responsiveness is awesome. Spool is almost as quick as a K04, yet I have 50-60 more whp up top. It'd be interesting to drive an S4-equipped car back to back with mine. I'll bet it's a little less responsive, yet climbs in the upper rpms even more.

You are right, the S4 spools a bit slower, but I believe it hits harder when it does spool, and it will hold that torque/power out longer. But probably not enough of a difference to justify an upgrade if you already have an S3.

 

[neganox]

But probably not enough of a difference to justify an upgrade if you already have an S3.

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