AdjustmentIdle Speed and Mixture Adjustment. Warm engine fully. Adjust curb idle speed to 900 rpm. Slowly turn mixture screw out until the engine speeds up, then keep turning out until engine starts to slow down slightly (overly rich). Screw in (clockwise) until engine slows down (lean). Turn back out til it runs fastest (Best Lean). Repeat for second barrel of the carburetor.

1. Dellorto Drla 40 Tuning

If a twin-carb setup, repeat for the second carburetorTo get a 'feel' for this adjustment, turn the screw by half turns clockwise and anticlockwise till you hear the engine speed up and slow down. Then fine turn with 1/4 turns. Do this repeatedly until you are confident of the results.

Dellorto dhla carburettor throttle linkage kit for twins & triples see more like this 42IDA Throttle Bodies replace 42mm Weber and dellorto carb carburetor Brand New. Dellorto DHLA are similar to the Weber DCOE carburetors, but have their own unique parts and some say a better design and look better. In essence, a single throttle lever, with its own balance screw Center Pull needs only one carb-pull, eliminating the separate throttle adjustments. The center floating linka has its own balance screw Album.

TuningTuning any carburetor is mythically difficult. However, DHLA is no more complicated than Weber or the Hitachis that come stock on Datsuns.

They are tuned basically the same way.SSS DHLA40 jetting specsVenturi: 28mmMain jet: 115Needle and seat: 1.50Float:.01Starter jet: 70Starter emulsion tube:.01Idle jet holder:.01Idle jet: 50Air corrector: 200Emulsion tube:.01Aux venturi:.01Pump jet: 33Pump delivery: 7.5To suit SSS A12 engine with mild rally cam (see specs in SSS section) and 4-2-1 tubular headersAlso see:NOTE: When removing and re-inserting the Pump Jet, be sure to line up the passages. See. Choose DHLA 40 for A-series engines. Or DHLA 45 for larger engines. Choose appropriate venturi size, perhaps 26mm is best for stock A12 engine.

Available from 25 mm to 37 mm in increments of 1mm. Part number 8383.25 to 8383.37 at Eurocarb. Auxiliary venturi from size 1 to 4. DHLA Starter - tuning for cold starting. starter jet sizes from 48 (3315.48) to 105 (3315.105).

starter emulsion tube 1 to 4 (7482.1 to 7482.4). Accelerator Pump. Pump Jet sizes 33 to 60. Pump rod adjustment. Screwing the nut tighter increases fuel delivery, turning it anti-clockwise reduces delivery.

Dellorto Drla 40 Tuning

Combination of Jet and tightness works 1) Time, shoot for 1 second 2) volume. Probably twin carbs will be within 1/2 turn of each other to deliver the same volume. Test this by actual measurement using a CC vial.