SKU: 86078173870

Holley LS1/LS2/LS6 Ultra Lo-Ram EFI Intake Manifold (HO300-621)

Sale price$1023.75 Regular price$1137.50
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Description

Holley LS1/LS2/LS6 Ultra Lo-Ram EFI Intake Manifold (HO300-621)HO300 621 HOLLEY MODULAR LO RAM INTAKE Suit Single GM 105mm Throttle Body Part Number: HO300 621 The Holley LS1 2 6 Ultra Lo Ram intake manifold kits are designed for GM LS Gen III and IV engines equipped with GM LS1 2 6 (cathedral port) cylinder heads. These intake manifolds will work with OE or aftermarket cylinder heads. The Ultra Lo Ram intake manifolds are designed for forced induction (supercharged or turbocharged) engine applications and the

HO300-621 - HOLLEY MODULAR LO-RAM INTAKE

Suit Single GM 105mm Throttle Body

Part Number: HO300-621

The Holley LS1/2/6 Ultra Lo-Ram intake manifold kits are designed for GM LS Gen III and IV engines equipped with GM LS1/2/6 (cathedral port) cylinder heads. These intake manifolds will work with OE or aftermarket cylinder heads. The Ultra Lo-Ram intake manifolds are designed for forced induction (supercharged or turbocharged) engine applications and the 105 mm throttle body part number 112-581 or similar models. The base intake manifold is designed with a lower overall height to fit under a stock or mildly modified hood. 
The 300-621 Lo-Ram plenum entry was configured to provide a very low profile modular intake manifold suitable for turbocharged or centrifugally supercharged engines. 
The fuel rail kits come with two sets of brackets. A set for long (usually standard length) fuel injectors and a set for short (such as Pico, or LS7) fuel injectors.
Features:
Designed for GM LS Gen III and IV engines equipped with GM LS1/2/6 (cathedral cylinder heads
Designed for forced induction (supercharged or turbocharged) engine applications with peak power at 7000-8000 rpm depending on the application.
With forced-induction and the short runner length the engine rpm at which peak power occurs is more likely to be coupled to the supercharger or turbocharger being used
Modular design allowing the use of front-feed plenum entry

Intake design facilitates custom inlet duct and throttle body placement

Low height to fit under a stock or mildly modified hood in the front configuration
Front entry plenum flange allows design & fabrication of special throttle body adapters or inlet ducts for custom installations
Clears 4th Gen Camaro and C5 Corvette cowls and hoods without modification
High volume fuel rails and mounting hardware included with ¾”-16 o-ring ports (8 AN)

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Exchange/Return Notes
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SKU: 86078173870

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shoehog
Grantham, US
★★★★★ 5
A T-Shirt to live in
Color: White, Size: X-Small
This crew neck if super soft and work really well under cashmere sweaters. Wish they came in more colors
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Reviewed in the United States on January 12, 2026
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Janice Wu
New York, US
★★★★★ 5
Great so far
Color: White, Size: X-Small
Loving this shirt so far, i just got it. It is soft and comfortable and I wish for more colors I wonder how it will do in the wash
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Reviewed in the United States on November 12, 2025
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AgH
Phoenix, US
★★★★★ 3
Buy at least 2 sizes bigger than you need.
Color: Heather Grey, Size: Large, Color: Heather Grey, Size: Large
These shirts are pretty soft, you can tell they are different from other shirts boasting natural fibers. They don't compare to the thin or drape from onno shirts but its less than half the cost. I have ordered 3 more, but with that being said... the shrinkage was unreasonable. The shirt lost 4 FULL inches in length and a little over an inch in width. Now, taking into consideration that I am a full grown hobbit this shirt is unsuitable for anyone over 5ft tall. I this would literally be a crop top on a average size adult and it is a large! I'm going to test out 2 other styles and the xl in this shirt but holy cow i really want to wear it because it's thin and will protect me from the sun but it's way too small now. I really hate the feeling of dry fit uv protection clothing, and this is so much better. Just wish I could wear it and didn't waste 20 bucks washing a shirt I can only wear in the comfort of my own home in fear of being arrested for indecent exposure. I would estimate shrinkage is more than one size.
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Reviewed in the United States on May 25, 2025
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Liz Newman
Louisville, US
★★★★★ 5
Comfortable and cool. Does not ride up.
Color: 01-multicolour (4-pack), Size: Medium
Extremely comfortable. Stays cool. Ample coverage. Quality material. They do not creep up. I ordered a medium which I generally take a size small. I have reordered and will reorder again to add more colors to my collection.
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Reviewed in the United States on May 18, 2026
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Janola
Houston, US
★★★★★ 5
Great Value for Cool Thigh Protection
Color: 02-multicolour (4-pack), Size: XX-Large
For the price, I'm not sure there are better women's boxer shortlettes anywhere. I've tried more expensive brands, and for quality and cooling, these are right up there. I have other bamboo viscose undies that still get gross when I get sweaty in the summer, but these, with the large mesh panel, really help wick away a lot of that moisture, keeping you feeling dryer and cooler. I find that the leg openings are comfortable and don't roll up! and the waist band doesn't dig, nor does it roll down. These do not provide any compression, and I wasn't looking for any. I just wanted some cooling, thigh protecting women's boxers that wouldn't break the bank. These are them! Bonus- I've washed them and put them in the dryer (following their instructions), and they haven't shrunk; they look about the same and are nice and soft.
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Reviewed in the United States on July 28, 2025

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