Fitment questions?
Call (855) 786-7101 or text (801) 304-3141.
Real people. Real answers.
Product details
EMPI part 43-5415-0 is a 1.70 main-circuit air correction jet for 40/44 HPMX, 40/44/48 IDF, EPC 48/51, 48 IDA, and DCOE carburetors, used to fine-tune the mixture at high engine speed. If an engine pops or feels lean while holding a steady speed high in the rev range, the usual fixes are a larger main jet or a smaller air corrector, and stepping from a 1.75 down to this 1.70 is the second of those moves. A smaller number means less air bleed and a richer top end.
The air corrector mostly shapes the mixture from about 3,500 rpm up, so treat it as a finishing adjustment after the main jet is close. Watch for the look-alike 1.70 sold as 43-5439-0, which is EMPI's air jet for EPC 32/36, EPC 34, and DGV-type carburetors.
Technical Details
- Manufacturer: EMPI
- Manufacturer part number: 43-5415-0
- Type: main-circuit air correction jet (77401-type)
- Size: 1.70
- UPC: 707924223705
- Sold as: each
Fitment & Compatibility
Fits 40/44 HPMX, 40/44/48 IDF, EPC 48/51, 48 IDA, and DCOE carburetors, including the EMPI HPMX kits sold for VW Type 1, 2, 3, and 4 engines. Order one per barrel, so four for a dual-carburetor engine.
Installation & Tuning Notes
Test at steady rpm in gear under load, since hard launches tell you little about the main circuit. Keep every barrel on the same size.
Common Questions
Is this sold as a set of four?
No. EMPI sells 43-5415-0 as a single jet.
Does the 1.70 fit a Weber DCOE?
Yes. EMPI lists the DCOE along with the HPMX, IDF, EPC 48/51, and 48 IDA.
Should I change the main jet or the air jet first?
Main jet first. The air corrector is the finer top-end adjustment.
