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Product details
EMPI 43-5310-0 is a 1.55 main jet that sizes the main-circuit fuel flow in PMO carburetors and in 40/44 HPMX, 40/44/48 IDF, EPC 48/51, 48 IDA, and DCO/DCOE carburetors. It is the main jet in PMO's 46mm street kit for 3.2 to 3.4 liter Porsche 911 engines (PM-O805-0), which pairs 155 mains with 38mm chokes, 180 air correctors, F16t emulsion tubes, and 55 idle jets. PMO's performance kit for the same displacement steps up to 165 mains and F7t emulsion tubes.
That jump shows a jet number only means something next to the choke, air corrector, and emulsion tube it runs with. The 1.55 is also the middle main in PMO's 46mm jet set (PM-O852-0), between the 1.50 and 1.60. PMO carbs accept standard IDF jets, so this EMPI part fits them the same way it fits an IDF.
Technical Details
- Manufacturer: EMPI
- Manufacturer part number: 43-5310-0
- Jet type: main jet
- Size: 1.55 mm
- Carburetors: 40/44 HPMX, 40/44/48 IDF, EPC 48/51, 48 IDA, and DCO/DCOE
- Sold as: each
Fitment & Compatibility
Fits PMO carburetors and EMPI's carbs above. Progressive carbs such as the Weber 32/36 DGV take a different jet.
Installation & Tuning Notes
Set ignition timing, fuel pressure, and float level before touching the jets. Change one component at a time, record what you tried, and test with a wideband lambda gauge or on a rolling road.
Common Questions
Is 1.55 the stock main jet for a PMO 46mm kit?
For the 3.2 to 3.4 liter street kit, yes. The performance version runs 165s.
How big a change is going from 1.50 to 1.55?
One 0.05 step, the smallest increment in EMPI's main jet series for these carbs.
Call PMB Performance with jetting questions. We have tuned classic VW and Porsche carburetors for more than 20 years.
