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Exclusive to Mace Engineering is our design-registered plenum spacer to suit the Ford Boss 260 and 290 V8 engines.
What is a plenum spacer and what does it do?
A plenum spacer thermally separates the plenum cover and intake manifold. Its main purpose is to improve air distribution between cylinders by slowing down the air speed inside the plenum chamber. As a result there is less of a pressure drop inside the plenum chamber between cylinders, and less air momentum, resulting in better air distribution and power. The change in airflow characteristics is shown in the diagram below.
Not only will our spacer help you make more power, it will also help prevent any costly rebuilds through dangerous lean outs that occur with standard manifolds in high horsepower/boost applications (due to poor air distribution).
In addition to improving air distribution between cylinders, the increase in plenum volume also has a positive effect on bottom end torque.
The fact these spacers are manufactured from the same thermal resistant composite material as our manifold insulators means further horsepower gains are possible due to the reduction in heat soak.
Key benefits:
Contents:
Vehicle Fitment Guide

Note: Installation is very straight forward, requiring only the removal of your plenum cover to install the plenum spacer.
We're happy to help.
$130.00
Selling fast!
Get yours while you can.