Moroso Advance Curve Kit for GM HEI Distributors — 72300 Recurve Kit with 3 Springs & Precision Weights

This kit is a drop-in solution for GM HEI distributors that changes the distributor's advance characteristics without replacing cores or electronic components. It includes precision-stamped weights, a centerplate, a built-in stop for the adjustment screw, and three spring sets so you can tailor the rate and total of mechanical advance. The kit arrives with step-by-step installation instructions to help you make measured timing changes for street, strip, or custom builds.

How does the advance curve kit change distributor timing?

The Moroso kit alters the distributor's mechanical advance mechanism so the centrifugal advance reaches full timing at a chosen engine speed. By swapping springs and positioning the stop screw, you control both the speed at which advance builds and the maximum degrees of mechanical advance delivered.

• Recurves distributor lift to shift full advance to the target RPM range
• Three spring options let you pick slow, medium or fast advance rates
• Precision weights and centerplate provide stable, repeatable behavior
• Built-in stop prevents the screw from backing out during operation

Will this kit fit my GM HEI distributor and how hard is installation?

The Moroso 72300 is designed specifically for GM HEI-style distributors; fitment is straightforward on compatible units. Basic mechanical skills and common tools are all that's required, and the included instructions guide you through disassembly, parts swap, and reassembly.

• Formulated for GM HEI distributors—verify part compatibility before purchase
• Clear, step-by-step instructions included in the kit
• Installation typically requires hand tools and a timing light for final adjustment
• No permanent machining or complicated electronics needed

What performance benefits can I expect after recurve?

Changing the advance curve can improve throttle response, optimize midrange power, and help the engine reach peak timing where it makes the most power. Results depend on the engine combination, cam timing, and ignition system, so adjustments should be validated on the road or dyno.

• More timely spark advance where the engine needs it most for better response
• Reduced erratic timing thanks to smooth, precision-stamped components
• Ability to tune advance rate and total with three spring choices
• Secure stop screw prevents unintended timing drift during use

Who is this for: The Moroso 72300 Advance Curve Kit is aimed at engine builders, hot-rodders, and DIY mechanics who want to refine mechanical distributor timing on GM HEI-equipped engines. It’s ideal for street performance upgrades, race applications, or anyone rebuilding a distributor who requires a reliable, adjustable mechanical advance solution without replacing the entire unit.