FAST
FAST LSXRt Manifold LS3 102MM High HP Runner - Black
SKU: F003 146105B
Description
Part #: 146105B
This LSXRT Intake Manifold gives LS3 engines with rectangle-port cylinder heads even more plenum volume for all-out racing. Best suited for high-RPM race engines, this manifold creates proven gains of 30+ horsepower over the FAST LS3 Street Manifold at high RPM. The raised 102mm throttle body location optimizes the larger, less restrictive High HP runner design, creating more power. It also clears truck drive accessories.
Features:
- 102mm inlet also works w/ OEM electronic 78/90mm or aftermarket 90/92mm throttle bodies for high flow and minimal restriction (three-bolt electronic throttle bodies require an adapter).
- Advanced polymer material is strong, lightweight and cools intake charge for enhanced power.
- Big gains in rear-wheel HP yet retains factory fitments and under-hood clearance requirements.
- Replacement runners can be purchased separately
- Designed specifically for rectangle port LS3/L92 engines in car and truck applications where hood clearance is not a concern.
- Modular design allows for easy removal and porting of intake runners.
- Proprietary precision injected polymer design offers light weight, excellent strength and lower heat soak propensity, especially compared to aluminum designs.
- Features integrated nitrous bungs and a bolt-on fit that allows the use of factory truck accessories.
- Includes our High HP runners that deliver gains of 30+ HP over standard runners.
- Feature larger plenum than the lower profile LSXr High HP intake manifold.
Building upon the popular LSXrt intake manifold, the new LSXrt gives LS3/L92 engines more plenum volume for all-out racing. The raised throttle body location optimizes the larger, less restrictive High HP runner design, creating more power.
This product may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.
Fitment
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Specifications
| Brand | FAST |
| Part Number | F003 146105B |
Videos
Dyno Tested: FAST 102mm LSXR Intake Interchangeable Runners
Fast LSXR 102mm Intake Manifold | What Is It?!
Speed Secrets: FAST LSXR Intake Runner Set Test
Fast 102 Intake Install!
LS INTAKE TEST-STOCK TRUCK vs TBSS vs FAST LSXRT-PRICE VS POWER
FAST: LSX Interchangeable Runner Dyno Testing
Unboxing the GM LS3 LSXrt 102mm High HP Runner Intake Manifold from FAST
FAST LSXR INTAKE-IS IT WORTH $1000? HOW MUCH HP DOES IT ADD? LSXR VS CHEAP, JUNKYARD TRUCK INTAKE
Advantages and disadvantages of F.A.S.T LSXR Intake manifold
FAST: LSX Interchangeable Runner Dyno Testing
FAST LSXR Intake Manifold Install on 2013 Camaro - Summit Racing
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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