With a naturally aspirated spreadbore combination, the two things you need to determine are power level and whether you want to retain a Quadrajet™ style EFI system. If you want to hear those big QJet secondaries roaring when you go WOT, the Sniper EFI Quadrajet™ will handle up to 500 horsepower. Due to the smaller primaries, we had to scale fueling back to maintain proper fuel distribution.
If you power demand exceed 500 horsepower but are less than 650, the standard Sniper EFI system will work for you, thanks to its dual pattern flange. Since it has four equal-sized throttle bores, we did not have to dial back fuel flow like the Sniper EFI QJet.
Sniper EFI Quadrajet™
- Designed to deliver the signature Rochester Roar at Wide Open Throttle!
- Fits most stock Rochester Quadrajet™ (Q-Jet) air cleaners
- Supports up to 500 horsepower with four 100 lb/hr injectors
- Requires external fuel pressure regulator such as: part # 12-886 or 12-879
Sniper EFI 4150
- Dual Pattern bolt on carburetor replacement, designed to fit 4150 Flange & Spreadbore manifolds - (Spread Bore Sealing Plate Part #9006 is recommended)
- Supports up to 650 horsepower with four 100 lb/hr injectors
- Internal fuel pressure regulator eliminates the hassle of plumbing an external fuel pressure regulator (Preset to 58.5 PSI)