Trackspeed EFR Turbocharger System


There is no current ETA for availability of our EFR kits due to ongoing supply chain issues. Please email us if you would like to be notified when kits are available in the future. Please do not place an order using this page. 


This DIY system includes our EFR-specific manifold, a BorgWarner EFR B1-frame turbocharger, EFR-specific inconel exhaust studs, a stainless 3" downpipe, and our EFR-specific braided oil and hard coolant lines. The end user will need to build an intercooler system, turbo intake+air filter, and heat shields for the brake master cylinder and other rubber items near the turbo

Use this DIY system to provide a robust base for your own race turbo build. 

This system is designed for motorsport applications and is not intended for use on pollution-controlled vehicles. 


The wait is over. Trackspeed's DIY EFR Turbocharger System is the result of seven years of exhaustive research and development into turbocharged Mazda Miatas, and it represents the culmination of everything we have learned since we started racing turbocharged Miatas in 2007. By combining the most advanced turbocharger on the market (BorgWarner EFR) with a high-quality cast stainless steel exhaust manifold and stainless steel mandrel bent exhaust components, we are able to offer a kit which out-spools, out-responds, and out-performs the competition in every measurable metric. 

Our kit starts with the best manifold on the market, bar none. Shell mold cast in the United States from 347 stainless steel, our manifold provides the performance of a custom welded tubular manifold and the reliability of a cast manifold in a single package. 

Mated to this manifold is BorgWarner's EFR turbocharger, which features a titanium aluminide turbine wheel for unmatched response and spool, an internal wastegate which outperforms comparable external wastegates, an integrated bypass valve for simplicity and ease of installation, and an integrated electronic boost controller for easily adjustable boost levels. The EFR6258 is our standard turbocharger, providing excellent spool and unmatched response while still providing up to 325whp without a decrease in efficiency. The EFR6758 maintains the exceptional spool and response of its baby brother but lifts the power cap to over 450whp. 

Fastening the two is an EFR-specific version of our legendary Inconel Stud Kit. Imitated by other turbo vendors, but never emulated, our kit combines proprietary Inconel fasteners with Cotronics high-temperature chemical threadlocker and stainless-steel Stage8 fasteners to ensure your turbocharger stays securely fastened in even the most extreme environments. 

Our EFR-specific 3" downpipe is compound mandrel bent to eliminate unnecessary weld joints, and includes a dedicated wideband O2 sensor bung and stainless flex section for improved reliability. 

Manifold specs:

  • Fits 1994-2005 Miatas and 1990-1993 Miatas with 1.8L engines
  • Shell mold casting process ensures excellent dimensional accuracy and surface finish
  • 347SS stainless steel will withstand extreme abuse from track days or racing
  • True 4-1 low-volume design ensures maximum response
  • A/C and P/S compatible
  • EGR compatible (requires custom EGR pipe)
  • Cast and machined in the United States
  • Designed for BorgWarner EFR B1-frame turbos
    • EFR6258: 150-325whp, ideal for pump gas and stock engines
    • EFR6758: 250whp-450whp, ideal for built engines or flex-fuel (E85)
    • EFR7163: 300whp-500+whp, ideal for those with questionable judgement

Downpipe specs:

  • Fits 1994-2005 Miatas and 1990-1993 Miatas with 1.8L engines
  • 3" diameter from inlet to outlet for maximum spool and power potential
  • Compound CNC mandrel bent construction eliminates several weld joints and ensures dimensional accuracy
  • 304SS stainless steel retains heat and resists corrosion better than mild steel
  • 2-piece construction reduces cost, but once assembled, the downpipe can be installed as a single piece
  • Stainless steel flexible joint isolates the manifold/downpipe from exhaust system motion and stress
  • Connects to your factory catback or aftermarket exhaust (3" recommended)
  • 2004-2005 MSM owners: You MUST use an aftermarket 2001-2005 NB 2.5" or 3" exhaust when using our downpipe

Oil/Water line specs:

  • Fits 1994-2005 Miatas and 1990-1993 Miatas with 1.8L engines
  • Oil lines are braided SS construction with high-temp firesleeve coating
  • Water lines are seamless 304SS tube with all steel fittings and silicone connector hoses



Additional Info