Choose the Right Aftermarket EFI System for Your Build

Upgrading to an aftermarket EFI system is one of the most effective ways to modernize your engine, improve throttle response, and enhance fuel efficiency. But not all EFI systems are created equal, and choosing the wrong one can cost you both performance and money. Whether you’re building a street cruiser, weekend track car, or a fully custom showpiece, this guide will help you select the EFI system that matches your goals.

Types of Aftermarket EFI Systems Explained

Choosing the right system starts with understanding the three main EFI configurations available:

1. Throttle Body Injection (TBI) Systems

Overview: Combines the look of a carburetor with the benefits of fuel injection.
Pros: Simple installation, cost-effective, great for street and mild performance applications.
Ideal For: Classic builds, entry-level EFI conversions.

2. Multi-Port EFI (MPFI) Systems

Overview: Each cylinder gets its own injector, offering precise fuel metering.
Pros: Superior power delivery, better fuel economy, cleaner emissions.
Ideal For: High-performance builds, modern engines, racers needing precise tuning.

3. Stack Injection Systems

Overview: Individual throttle bodies per cylinder, often with exposed velocity stacks.
Pros: Stunning visual impact, high-end air delivery, razor-sharp throttle response.
Ideal For: Show cars, race applications, and custom performance engines.

Key Considerations Before You Choose

Not all systems are right for every build. Before you buy, ask yourself:

1. Engine Type & Compatibility

Are you running a small block, big block, or custom engine?
Consider manifold fitment, injector placement, and sensor locations.

2. Performance Goals

Is your goal low-end torque, high-RPM horsepower, or balanced drivability?
TBI may suffice for cruising, while stack or multi-port is ideal for aggressive performance.

3. Budget and Upgrade Path

Some systems allow modular upgrades (e.g., start with TBI and move to MPFI later).
Consider long-term tuning, support, and parts availability.

4. Tuning Support

Will you need self-tuning or full custom tuning software?
Look for systems with good documentation and tech support. Borla Induction Support is a great place to start.

Checklist: What You’ll Need for a Complete EFI System

Choosing an EFI system means more than just the control unit. Here’s what else to consider:

Component	What to Look For
Throttle Body	Choose by bore size and TPS compatibility. See Kits →
Intake Manifold	Match it to engine type and EFI style. Browse EFI Components →
Injectors	Size according to fuel pressure and horsepower goals.
ECU/Controller	Look for programmable, user-friendly software.
Fuel Delivery System	Pumps, regulators, and filters must match EFI pressure.
Sensors	MAP, IAT, TPS, O2, and coolant temp sensors required.

Common Mistakes to Avoid

Mismatching components (e.g., carb-style manifold with MPFI)
Overlooking tuning options (cheap kits may lack adjustability)
Ignoring fuel system needs (EFI requires higher pressure than carb setups)
Skipping professional support (use resources like Borla’s contact page for guidance)

In Summary

Choosing the right aftermarket EFI system is about more than horsepower numbers, it’s about selecting a system that aligns with your engine, your goals, and your technical ability. Whether you’re building for the street or the strip, the right foundation will lead to a smoother install and better results.

Need help selecting the right kit?
Explore Borla Throttle Body Kits or EFI Components, or contact our team for expert advice.

We build excitement. Start with the right EFI foundation.