MSD Distributor Advance Kit 8464 for Pro‑Billet Distributors — 4 Springs & 3 Stop Bushings, Tune Mechanical Advance

This kit gives you the small hardware needed to tune mechanical advance behavior on MSD Pro‑Billet distributors. It includes multiple springs and stop bushings so you can adjust how quickly and how far the distributor’s mechanical advance responds as engine RPM rises. The parts are made for MSD distributors only and are intended for performance tuning and maintenance rather than universal distributor fitment.

How does this kit change distributor advance characteristics?

Changing springs and stop bushings alters the timing curve delivered by the distributor’s mechanical advance. Softer springs let the advance come in earlier and quicker, while stiffer springs delay and slow the advance. Stop bushings limit the total degrees of mechanical advance for applications that need conservative timing at high RPM.

• Four different advance springs to adjust rate of advance.
• Three stop bushings to limit maximum mechanical advance.
• Mix-and-match parts to create a custom timing curve for your engine.

Which engines or setups benefit from swapping these parts?

Any engine using an MSD Pro‑Billet distributor and needing refined mechanical timing can benefit. Street engines, mild performance builds, and race motors all use spring/bushing changes to match camshaft, intake, and converter characteristics. Use conservative settings for high static timing engines or aggressive springs for engines that need more timing at mid‑range RPM.

• Street/strip V8s seeking improved throttle response.
• Engines with aftermarket cams that shift the desired timing window.
• Setups needing reduced top‑end advance to avoid detonation.

How easy is it to install and tune the kit on an MSD Pro‑Billet distributor?

Installation is a straightforward mechanical job familiar to most DIYers. Remove the distributor weights to access the springs and bushings, swap in the chosen components, and reassemble. Small tools and basic mechanical knowledge are all that’s required, but keep a record of original parts so you can return to stock settings if needed.

• Simple disassembly of distributor weights to reach springs and bushings.
• No specialty tools required—basic wrenches and screwdrivers suffice.
• Document original configuration before making changes for easy rollback.

Will these parts work with non‑MSD distributors or affect electronic advance?

The MSD 8464 kit is manufactured for MSD Pro‑Billet distributors and is not guaranteed to fit other brands. These components modify the mechanical advance only and do not alter any vacuum or electronic advance systems. If your distributor combines mechanical and electronic advance, changing these parts only affects the mechanical portion.

• Designed specifically for MSD Pro‑Billet distributors—compatibility not assured for other makes.
• Alters mechanical advance; vacuum/electronic systems remain unchanged.
• Use with MSD distributors to maintain expected fit and function.

Who is this for: The MSD 8464 Distributor Advance Kit is for enthusiasts, tuners, and mechanics who own MSD Pro‑Billet distributors and want granular control over mechanical timing. It’s ideal for people refining engine performance after cam or intake changes, those reducing top‑end advance for detonation control, or anyone performing maintenance and needing replacement springs and bushings. If you want to tweak your distributor’s RPM‑dependent timing curve while retaining MSD’s engineered fitment, this kit provides the basic parts to get there.