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Air and Fuel› Intake Manifolds and Components
FAST
Replacement Lower Shell LSXr 102mm LS1
SKU: F003 146301
Easy — 1–2 hours
Overview
Show original supplier description
Part #: 146301
Constructed from the same advanced polymer material as the original FAST LSX 92mm Intake Manifold, but now in the popular black color, the LSXR offers a host of benefits over aluminum aftermarket intakes, including lighter weight, increased strength and improved heat dissipating characteristics.
Features:
- Replaces lower shell for cathedral port LS1, LS2 and LS6 engines.
- Modular design allows for fast and easy disassembly
- Removable runners allow for porting
- Improved throttle body sealing flange and o-ring gasket
- High quality polymer materials resist the heat sink effecct of aluminum
- Maximizes potential of other engine performance upgrades like cylinder heads
- Designed to work with FAST Big Mouth and Big Mouth LT Throttle Bodies
- Includes stainless steel bolts, threaded insert throttle body mounts and necessary mounting hardware.
This lower shell replaces the lower shell that came with the LSXr 102mm intake manifold for LS1, LS2 and LS6 engines.
Vehicle Symptoms
- Rough idle after cold start
- Check engine light for lean condition
- Loss of power under acceleration
- Hesitation or stumble on throttle tip-in
- Vacuum leak hissing sound from intake area
Diagnostic Codes
- P0171 – FT Malf (B1)
- P0174 – FT Malf (B2)
- P0300 – Random or multiple cylinder misfire Det
- P0505 – Idle Air Ctrl Sys Malf
- P0506 – Idle Air Ctrl Sys RPM Low
- P0507 – Idle Air Ctrl Sys RPM High
Relevant Conversations
- LS1 rough idle after intake manifold swap
- P0171 code on LS2 after installing FAST intake
- FAST LSXR lower shell vs OEM replacement
- How to replace FAST LSXR intake manifold lower shell
- LS6 intake manifold leak symptoms and fixes
- Best gasket for FAST LSXR 102mm intake
- LS1 intake manifold lower shell replacement cost
- FAST 146301 install tips and torque specs
- Cathedral port intake manifold lower shell upgrade
- LS2 P0300 misfire after intake manifold install
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.
Fitment
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Specifications
| Brand | FAST |
| Part Number | F003 146301 |
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