The facts

This page is based on my own experiments with L-jet in an Alfa 2.0 engine. Any information here is based on educated guesses and might not represent absolute truth.


The good, bad and the ugly

The good.


  • Instant response in fuel mixture. No lag.
  • Automatic compensation for air-temp.
  • Idle cut-off improves engine braking and mpg in town.

    The Bad.


  • No compensation for air-pressure.

    The Ugly.


  • The single-throttle design is not suitable for wild cams/open headers. The contant vacuum in the plenum chamber causes exhaust reversion at small throttle plate angles/high vacuum. This destroys mpg and idle and is the reason why I changed back to carbs. For wild cams the solution is to fit multiple throttles (Available at high price from Lumenition, etc.).
  • The flap-type air-flow meter is an considerable restriction in air-flow.

    Suggestions on installing an injection system.

  • Go for the multiple throttle set-up, buy or make and ecu with mapping facilities and built-in ignition control.

    DO NOT BUY AN L-JETRONIC UNLESS YOU PLAN TO USE MULTIPLE THROTTLES WITH IT !!!!

    These are the conclusions I have made from experiments.
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