The Turbo Esprit was equipped with Dellorto carburetors from the factory. Exported cars received the DHLA 40 H. UK and North American cars received the DHLA 45 M.
| || DHLA 40 H || DHLA 45 M |
|Choke ||36mm ||37mm|
|Main Jet ||185 ||168|
|Main air corrector jet ||200 ||230|
|main emulsion tube ||7772-12 ||7772-13|
|Idle jet ||40 ||52|
|Idle jet holder ||7850-7 ||7850-9|
|Float weight ||8.5 g ||8.5 g|
|Float setting height ||14.5-15.0 mm ||14.5-15.0 mm|
|Needle valve ||200 ||200|
|Pump jet ||48 H (special) ||38 H|
|Starter jet ||80 ||80|
|Starter emulsion tube ||7482-3 ||7482-3|
|Slow running speed ||850 rpm ||950 rpm|
|Idle CO level (hot) ||1.0% ||0.8%|
|Pump delivery ||7cc/20 strokes ||8cc/20 strokes|
|Power jet || ||110|
|Fuel Pressure at idle ||3.5 lb/in2 ||3.5 lb/in2|
You can get carburetor parts and information from Eurocarb, Ltd.
Tuning your Carburetors
Tuning your carburetors is an almost impossible task without a rolling dyno or some kind of way of bringing your car up to speed and tracking the air to fuel ratio. The idea is that you want to lean out the car enough so that you get power, but not enough to burn things up and cause detonation. By watching what comes out of the exhaust you can discover what the mixture of air to fuel is (and what needs to be adjusted.)
The typical cost of a rolling dyno is about $350US for three hours of tuning. Most dynos will be set up to log your CO and your RPM so you can see how your engine reacts across the entire RPM band. Once you have the car tuned you can also see how much power your car makes on a rolling dyno.
As an alternative to renting a dyno, is to purchase a datalogger. For a little more than the cost of a four hour dyno session you can purchase a complete system that will allow you to log air/fuel and RPM.
Before you start turning screws and replacing jets you need to make sure that your carburetors are synchronized and are flowing the same amount of air. There are a variety of tools that will allow you to do this, but one of the best is the Morgan Carbtune II
]. A good manual is also very helpful in any tuning.