BNR S5 Turbocharger Upgrade

The S5 has a 3.5” compressor inlet and works with a 3.5” or larger intake pipe (same casting as S4).   All the tuners like using an aftermarket boost control going to your 44-46mm v band style wastegate!  The S5’s point milled, billet compressor wheel is rated for 62 lb/min air flow and is the larger of the 76mm Garrett compressor wheels with a 58mm inducer and 76mm exducer with 3mm compressor tip height extension.  Our S5 is comparable to the competition’s GTX 3076, but what separates BNR from the others is our own custom, 44-46mm external wastegate, .82 a/r turbine housing!  This turbocharger on a forged engine with ported stock intake gets 20 psi by 3400-3600 RPM.  The first test car maxed out the intake and the 6 port injection at 515 RWHP at 32 psi!   Axillary port injection is needed to go higher than stock fuel limitation  (370 WHP).  The S5 has the capabilities for 550 WHP without sacrificing response.  The S5 spools better than the competition’s 3076 by approximately 300 RPM even with the big turbine housing!    We lowered the price recently because we stopped making the oil return lines!  OIL LINE DETAILS HERE!

Here is what you get with the S5 turbocharger upgrade!

• GT30 Turbine wheel
• 58mm/76mm point milled billet compressor wheel (62 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 .82 a/r turbine housing with 44 mm wastegate v-band
• 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!

BNR Supercars specializes in the Mazdaspeed3 and Mazdaspeed6 turbochargers. 

Peak numbers are not what we are into.  We like designing turbocharger upgrades that produce maximum under the curve power and torque.  It makes these cars much more responsive and fun to drive on the street.  When you get greedy and go for that peak number, it kills the bottom and mid-range torque.   No bottom end torque makes the engine not as responsive for autocross/road racing and in BNR's opinion not as fun to drive!

These engines are doing very well handling 400-450 WHP with the stock bottom end.  Most people looking for a reliable replacement over the stock smoking KO4 usually go for the S1 or S2 turbocharger models since a tune isn’t required.  If your car is fully bolted with high performance fuel pump internals we suggest an S3 with a tune.  Fully bolted with added methanol injection go with the S4 and a tune.   Stock engine internals, don’t even think about doing an S5 or S6!

*Divorced down pipes do not work with BNR turbocharger upgrades!  If they are used, the wastegate valves will not open properly causing extreme high boost problems!*

*Built engines need a custom oil supply line for turbocharger protection!  Click link for details!*

Mazdaspeed 3/6 Custom Oil supply line “Built engines only”

*S5 and S6 model turbochargers to cover the cost of the custom oil drain line! 

*Please note, turbos may ship directly from BNR, so please allow extra time for the turbo to be built and delivered.