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BNR S4 Turbocharger Upgrade


BNR S4 Turbocharger Upgrade

The BNR S4 version 2 turbocharger has a 3.5” inlet and works with a 3.5” or larger intake pipe.   All the tuners like using an aftermarket boost control solenoid with a single barbed wastegate actuator.  The S4’s point milled billet compressor wheel is rated for 53 lb/min air flow and is the smallest of the 76mm Garrett compressor wheels.  Our entry level 3076 is 4mm smaller on the inducer compared to the 3076 from our competition.   This is by far the most popular turbocharger on the Mazdaspeed and the MPS market!   Axillary methanol injection is needed to go higher than 370 WHP.  This unit will do up to 480 WHP without sacrificing response.  The S4 spools better than the competition’s 3076 by 500 RPM!    Here is what you get with the S4 turbocharger upgrade!

  • GT30 Turbine wheel
  • 54mm/76mm point milled billet compressor wheel (53 lbs/min flow rate)
  • High Performance 360 thrust assembly
  • Wide journal bearings
  • Rear journal bearing oil deflector (Diverts oil away from the turbine seal)
  • High Performance turbine seal
  • Balanced and blue printed to .5 gram/in2
  • BNR’s custom T2 bearing housing (uses all OE oil and water fittings)
  • BNR compressor housing (3.5” inlet, 2.25” outlet)
  • BNR .72 a/r turbine housing with 27mm wastegate port
  • Upgraded wastegate actuator (set at 18 psi)
  • All stainless hardware
  • 5 Layer stainless MLS turbine inlet/outlet gaskets
  • (9) M10 1.5 exhaust studs
  • Extended stainless water line (firewall side)
  • (4) 14mm copper sealing rings
  • year warranty!


Weight 20 lbs
Dimensions 12 × 12 × 12 in


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