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Air and Fuel› Intake Manifolds and Components
FAST
FAST Intake Manifold LSXHR LS1/2/6 (Cathedral Port)
SKU: F003 146303
Moderate — 2–4 hours
Overview
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Part #: 146303
The FAST LSXHR 103mm Intake Manifold is ideal for generating maximum power in boosted and naturally aspirated GM LS cathedral port engines. It ships with a set of tall removeable velocity stacks, however medium and short stack options can be purchased separately. This allows interchanging of the various runner lengths so racers can experiment with finding which combination makes the most power in their application. Its polymer construction is lightweight, very strong and virtually eliminates power-robbing heat soak that occurs with commonly available aluminum intake manifolds. The manifold has been optimized to make power from 5,000 to 7,500 RPM, with testing showing 20+ horsepower gains over competitor tunnel ram intake manifolds. The FAST LSXHR 103mm Intake Manifold is designed specifically with boosted applications in mind and is rated for up to 45psi of continuous boost pressure. The compound fuel injector angle aims the spray pattern for ideal atomization, resulting in maximum power production and superior drivability. Also included with the intake manifold are custom fuel rails and necessary hardware. A reversible top allows for forward- or firewall-facing throttle body installations. The intake manifold also features two nitrous nozzle bosses per runner for clean and easy direct port system installations. Additionally, its 103mm throttle body opening can be port matched up to 105mm.
FAST is expanding their line of the industry's first polymer tunnel ram-style intake manifold, ideal for generating maximum power in boosted and naturally aspirated GM Cathedral Port LS engines.
Vehicle Symptoms
- Lack of top-end horsepower above 5000 RPM
- Engine feels restricted at high RPM
- Inconsistent power delivery in boosted applications
- Heat soak causing power loss during extended runs
- Unable to reach target horsepower goals
Relevant Conversations
- Best tunnel ram intake for LS cathedral port heads
- FAST LSXHR 103mm vs Holley Hi-Ram
- LS intake manifold for 5000-7500 RPM power
- Tunnel ram intake for boosted LS engine
- LSXHR intake manifold review and dyno results
- How to install FAST LSXHR intake on LS1
- LS intake that reduces heat soak
- 103mm throttle body compatible intake manifold
- Tunnel ram vs single plane intake LS
- LS cathedral port intake manifold for high horsepower build
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
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Specifications
| Brand | FAST |
| Part Number | F003 146303 |
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