MAS EFI/TBI Distributor for GM 5.0L 5.7L 7.4L Engines — Red Cap, OEM-Fit (110-3952)

The MAS Small Block / Big Block EFI TBI Distributor is a direct-fit replacement distributor engineered to restore ignition timing and reliable spark for 1987–1997 GM 5.0L, 5.7L and 7.4L engines.

This MAS distributor is built as a plug-and-play OEM-style unit for a wide range of GM vehicles including Chevy C/K trucks, Camaro, Van, and Cadillac models from the late ’80s to mid ’90s. It replaces worn or failed original distributors with improved materials and precision components: a chromoly steel gear, heat-treated 20CR steel gearing, and compatibility with common OEM part numbers. The result is dependable fitment, consistent timing, and parity with factory mechanical and electrical interfaces for EFI and TBI systems.

Will this distributor fit my 1987–1997 GM engine?

Yes — MAS designed this distributor to match bolt pattern, electrical connector, and drive geometry for many GM V8s from that era. Confirm vehicle year, engine displacement, and OEM part references before purchase.

• Compatible with 5.0L (305), 5.7L (350) and 7.4L (454) engines.
• Vehicle examples: Chevy C/K trucks, Camaro, Caprice, El Camino, Blazer, Cadillac Brougham, and commercial chassis models.
• Cross-references include OEM and aftermarket numbers such as 110-3952, MSD 8366, Delphi CZ20001, Dorman 690-903.
• Designed for EFI and TBI ignition systems used in 1987–1997 GM applications.

How does the MAS distributor improve durability over a worn original?

MAS uses upgraded materials and precision production to reduce wear and extend service life versus aging factory units. Improved gear metallurgy and assembly tolerances help preserve timing integrity and minimize mechanical slop.

• Chromoly steel main gear for high-strength drive engagement.
• 20CR heat-treated gears for wear resistance under load.
• Factory-style electrical interfaces to avoid rewiring or splicing.
• Built to meet OEM form, fit and function with tighter quality control.

What do I need to know for installation and compatibility?

Installation is straightforward for anyone familiar with distributor service: set the engine to TDC, align the rotor and install the unit, then fine-tune timing as required. No modification should be needed if the replacement matches your original distributor’s part references and engine series.

• Follow factory timing procedure for initial setup and final adjustment.
• Verify cap orientation and plug wire order to avoid misfires.
• Confirm electrical connector matches stock harness before securing the distributor.
• One-year limited replacement warranty covers manufacturing defects.

Which part numbers and references match this MAS distributor?

This distributor cross-references many common aftermarket and OEM numbers, simplifying parts lookup and ensuring you get the correct replacement without guessing.

• MAS part corresponds to OEM 110-3952 and similar references.
• Also cross-listed with MSD 8366, Delphi CZ20001, Dorman 690-903, Accel 60109/59107.
• Works as a drop-in alternative to many HEI-style and EFI/TBI distributors used in late ’80s–’90s GM V8s.
• Product code often cited as HEI652R with distinctive red cap.

Who is this for? This MAS distributor is aimed at DIY mechanics, restoration shops, and owners of late-’80s to mid-’90s GM vehicles seeking a reliable OEM-form replacement. It’s suitable if you need a direct-fit upgrade for an aging or failed distributor on 305, 350, or 454 V8 engines and want improved gear material and a one-year replacement warranty. Always check fitment against your vehicle’s year, engine size, and original distributor part number before ordering.