Chevy BB 348/409 V8 HEI Distributor

The TSP HEI Distributor for the Chevy W-Series Big Block is a self-contained large-cap HEI ignition upgrade for the Chevrolet 348 CID (5.7L) and 409 CID (6.7L) W-series engines in carbureted applications from 1958 through 1965. The integrated HEI design combines the ignition coil, ignition module, cap, and rotor into a single unit, connecting to a single 12-volt source with no external coil, ignition box, or condenser required.

The Chevy 348/409 W-Series is not the same engine as the later Chevy big block. The W-Series — informally known as the "Porcupine" engine for its staggered valve arrangement — is a completely separate engine family from the Mark IV big block (396, 402, 427, 454) introduced in 1965. If your engine is a 396, 402, 427, or 454, this distributor is not the correct unit — see the TSP Chevy standard big block HEI distributor for those applications.

The 409 CID is one of the most iconic American V8 engines of the early 1960s, powering the full-size Chevrolet B-body lineup — Impala, Bel Air, Biscayne, and Caprice — as well as the El Camino and C-series trucks in their highest-performance configurations. Replacing the aging factory points-style ignition on a 348 or 409 with an HEI upgrade is one of the most impactful bolt-on improvements available for these vintage Chevrolets.

The 65,000-volt internal HEI coil delivers substantially stronger spark than a factory points-style distributor, supporting easier cold starts, cleaner idle quality, and more consistent ignition performance across the RPM range. A magnetic pickup trigger replaces the mechanical points contact and requires no routine maintenance. Both mechanical and vacuum advance are included, with a vacuum advance adjustment tool shipped with the distributor.

 

The Chevy W-Series Big Block — 348 and 409
The Chevrolet W-Series V8 was produced from 1958 through 1965 in two displacements — the 348 CID (5.7L) from 1958 to 1961, and the 409 CID (6.7L) from 1961 to 1965. Named for the "W" shape formed by its valve covers when viewed from above, and nicknamed the "Porcupine" for its unusually angled valve arrangement, the W-Series was Chevrolet's first true performance big block. The 409 in particular became one of the defining performance engines of the early muscle car era, powering multiple Super Stock drag racing championship seasons and immortalized in popular culture.

The W-Series is a completely different engine architecture from the later Chevy Mark IV big block (396, 402, 427, 454) that replaced it in 1965. The two families share no distributor compatibility — verify your engine is a W-Series 348 or 409 before ordering.

Performance Benefit
The 65,000-volt internal HEI coil fires spark plugs more consistently than a factory points setup across the full RPM range. Stronger, more consistent spark translates to easier cold starts, cleaner idle quality, and improved throttle response — particularly meaningful on vintage 348 and 409 applications where original ignition components may be sixty-plus years old. The magnetic pickup trigger holds timing accurately without the wear and drift that accumulates with points contact over time. Both mechanical and vacuum advance are included, and the vacuum advance adjustment tool allows the curve to be tuned for your specific engine combination.

COMPATIBLE WITH
CHEVROLET BIG BLOCK GEN. I (W) V8
• 5.7 L / 348 in³
• 6.7 L / 409 in³

NOTES
• Fits Chevrolet W-series big block 348 and 409 V8 applications.
• The 409 was available in passenger cars only — not available in trucks.
• Not compatible with later Mark IV big block Chevy engines (396, 427, 454).
• Designed for carbureted ignition systems only.
• This distributor is designed for a 12 volt electrical system with an alternator. 
• It is not compatible with a generator and cannot be used with a ballast resistor.
• Distributor gear compatibility should be verified with camshaft material before installation.

COMMON VEHICLE APPLICATIONS
Chevrolet Impala / Impala SS (348, 1958–1961; 409, 1961–1965)
Chevrolet Bel Air (348, 1958–1961; 409, 1961–1965)
Chevrolet Biscayne / Delray (348, 1958–1961; 409, 1961–1965)
Chevrolet El Camino (348, 1959–1960)
Chevrolet Suburban (348, 1958–1961)
Chevrolet C10 / C20 / K10 (348 truck only, 1958–1964)

SPECIFICATIONS
Trigger Type: Magnetic
Advance Type: Mechanical And Vacuum
Color: Available in Red, Black
Terminal Gender: Male
Mechanical Tach Drive: No
Slip Collar: No
Coil Included: Yes
Coil Type: Internal
Coil Output: 65000 V
Gear Material: Steel
Housing Material: Machined Aluminum
Ignition Box Required: No
Marine Use: No
Cylinders: 8
Vacuum Advance Adjustment Tool: Included
Installation Instructions: Included