V8 FIERO project

1988 Pontiac Fiero with a 4.6L Cadillac Northstar V8 swap


  • 1988 Pontiac Fiero that has the engine, transmission and electronics from a 1996 Cadillac Seville swapped over. Everything is made to look stock like it came from the factory.
  • The original 2.5L 4 cylinder in the Fiero came with 92 horsepower. The 4.6L V8 now installed has 300 horsepower. It also includes the 4T80E 4-speed automatic transmission.
  • All aluminum V8 doesn't weigh significantly more than the cast iron 4-cylinder it came with. Total weight is 2600 lbs.
  • Front hubs drilled to 5x115 pattern to match rear. Rear axles are from the Cadillac. Brakes are upgraded parts from a C4 Corvette.
  • The Fiero is a mid-engine car with the engine seated behind the driver. The drivetrain layout is transverse and able to fit many FWD GM engines and transaxles.
  • New for 2022 - freshly rebuilt 4.6L engine (including time serts)

32-Valve v8

DOHC V8 power

The 32-valve 4.6L V8 Northstar engine generates 300 HP @ 6000 RPM and 295 lb/ft torque at 4400 RPM. Fuel cutoff at 7000 RPM. This the L37 high-output version. PCM is a factory modded tune with VATS disabled. All modules from the donor car are installed. Custom Magnaflow high-flow exhaust installed. Best 0-60mph time on pump gas is 5.2 seconds. Pounds-per-horsepower ratio is 8.66, which is similar to a 2017 Chevy Camaro SS, which has a ratio of 8.61.


The Northstar engine makes a great driving and sounding swap for your Fiero project. On this website you will find the technical documents, wiring diagrams and notes to help you with your swap.