PRODUCT DETAILS
SpeedFactory Upper Coolant Fill Neck - Honda/Acura B-Series (B18C1/B18C5/B16A2)
Put together a custom cooling setup on your B-series and the thing just won't bleed right? Welcome to one of the most annoying parts of a clean build. When your fill point isn't at the top of the system, air gets stuck in there and your temps creep up no matter what you do. This SpeedFactory upper coolant fill neck solves it by moving the high point of your cooling system to a proper fill neck, so you get an easy place to pour coolant in and, more importantly, an easy place to get the air out.
The Fill Point Needs To Be At The Top
Here's the why behind it, and anyone who's burped a stubborn cooling system gets this instantly. Air floats to the highest spot in your system, so if your fill and bleed point isn't up there with it, you're never getting that trapped air out cleanly. And leftover air pockets are exactly what cause hot spots and climbing temps on an otherwise healthy motor. The catch is that on a tucked bay, a swap, or a custom radiator setup, the factory fill neck is usually relocated or deleted altogether, so you're left without a good high point. This neck gives you that high point back. Coolant goes in easy, air comes out easy, and you're not spending your whole evening chasing one last bubble.
Made In-House, Made To Fit
SpeedFactory fabricates these in-house from high-quality aluminum, with laser-cut head flanges so the neck seats clean and lines up right on your B-series head. On a cooling system you took the time to build properly, that fit and finish matters, this is a precise piece, not a rough weld-on you're fighting to make work. It plays nice with a custom radiator or SpeedFactory's own Race and Tucked radiators.
Pick Your Configuration
Choose the version that matches how your system's plumbed:
- -16AN for an AN-plumbed cooling system, tying straight into your AN lines.
- 32mm standard hose end for a conventional rubber hose connection.
Match it to the rest of your setup and it drops right into your plan.
Cap Compatibility
This neck works with SpeedFactory Type A radiator caps and Hybrid Racing Type F radiator caps, so make sure you've got a compatible cap to seal it and hold system pressure. If you don't already have one, add a compatible cap to your order so you're ready to button it up.
What You Get
- SpeedFactory upper coolant fill neck for the Honda/Acura B-series
- Relocates the high point of your cooling system for easy filling and air bleeding
- Made in-house from high-quality aluminum with laser-cut head flanges
- Choice of -16AN or 32mm standard hose end configuration
- Works with custom radiators and SpeedFactory Race/Tucked radiators
- Compatible with SpeedFactory Type A and Hybrid Racing Type F radiator caps
Fits These Cars
- 1999-2000 Honda Civic Si (B16A2)
- 1997-2001 Acura Integra Type R (B18C5)
- 1994-1997 Honda Del Sol VTEC
- Also fits B18C1-equipped cars
Note: SpeedFactory upper coolant fill neck for the Honda/Acura B-series (B18C1, B18C5, and B16A2), designed to ease filling and bleeding of a custom cooling system by relocating the system's high point to a proper fill neck. Fits the 1999-2000 Honda Civic Si, 1997-2001 Acura Integra Type R, and 1994-1997 Honda Del Sol VTEC. Compatible with most aftermarket radiator setups, including custom radiators and SpeedFactory Race and Tucked radiators. Manufactured in-house from high-quality aluminum with laser-cut head flanges for an accurate fit. Available in -16AN or 32mm standard hose end configurations; select the version that matches your cooling system plumbing. Designed to work with SpeedFactory Type A radiator caps and Hybrid Racing Type F radiator caps; a compatible cap is required to seal the system. One fill neck per order.