Car guys and performance enthusiasts, if you're running a Holley 4150 or 4160 carburetor (or similar square bore carbs), this phenolic spacer set can actually make a noticeable difference in your engine's performance! The 1/2 inch open design increases plenum volume for better high-RPM power while the four-hole configuration improves mixing speed for stronger low-end and mid-range torque. But here's the real benefit - the phenolic plastic construction acts as a thermal barrier, insulating your carburetor from engine heat. This keeps your fuel cooler, which means denser, more powerful fuel mixture reaching your cylinders. Cooler fuel = better performance, plain and simple. The kit comes with everything you need: three spacers, four bolts, four nuts, and four gaskets. Installation is straightforward if you're comfortable working on carburetors. It fits any square bore carburetor including Holley 4150/4160, Barry Grant, Carter, and others used on various small and big block engines. By extending the intake mixture column, it optimizes air/fuel distribution across different RPM ranges. Whether you're building a street machine, track car, or just want to squeeze a bit more efficiency from your engine, this spacer set delivers measurable improvements without breaking the bank. It's one of those bolt-on mods that actually works as advertised, giving you better throttle response and more consistent performance, especially in hot weather or under hard use. If you want to maximize what your carburetor can do, this spacer is a smart addition to your setup!
Free 30-day returns 
Free 30-day returns
