Chevy V8 Aluminum 45 Degree Water Neck - Black

• 45° aluminum outlet routes the upper radiator hose cleanly in tight bays

• Swivel design and included O-ring simplify hose alignment and leak-free sealing

• Fits Chevy Gen I small block (262-400 CID) and big block (396-454 CID) engines

• Black finish; also offered in black and straight/15°/90° angles

This 45° aluminum water neck creates the coolant outlet connection between the thermostat housing and upper radiator hose, with a black finish that gives the engine bay a clean, finished look. The 45° outlet angle helps route the upper radiator hose cleanly in engine bays where a straight or 15° neck wouldn't provide enough clearance, and an included O-ring seal helps reduce leak points at the housing connection.

This water neck is built for Chevy Gen I small block (262-400 CID) and Gen II/V/VI big block (396-454 CID) engines only — it is not designed for LS-based (Gen III/IV) small block engines, which use a different thermostat housing design. The swivel design allows the outlet to rotate for hose routing flexibility after installation, and mounting hardware is included.

Not all Chevy small block or big block engines share identical thermostat housing bolt patterns across every model year — confirm your engine's housing bolt pattern matches before ordering.

Engine Applications
Fits Chevrolet Gen I small block V8s from 262 through 400 CID and Gen II (Mark IV), Gen V, and Gen VI big block V8s from 396 through 454 CID. Suited to classic and performance builds, street rods, and restorations using a matching thermostat housing bolt pattern — LS-generation (Gen III/IV) small blocks use a different housing design and aren't covered by this fitment.

Installation
Confirm your thermostat housing bolt pattern and outlet angle before installing, since housing dimensions vary by engine year even within the same family. The included O-ring seals against the housing face, and the swivel outlet can be rotated after mounting to fine-tune upper radiator hose alignment without disturbing the seal.

What does this water neck do?
This water neck provides the coolant outlet connection between the engine's thermostat housing and the upper radiator hose, directing coolant from the engine to the radiator.

What engines is this compatible with?
This water neck is designed for Chevrolet Gen I Small Block V8 (262–400 CID), Gen II Big Block (Mark IV) V8 (396–454 CID), Gen V Big Block V8, and Gen VI Big Block V8 engines.

What angle is this water neck?
This is a 45-degree water neck. TSP also offers straight, 15-degree, and 90-degree versions for applications requiring different upper radiator hose routing.

What finish does this water neck have?
This water neck features a black finish. A polished finish is also available.

Does this include a gasket or seal?
Yes. An O-ring seal is included for installation.

Does this include mounting hardware?
Yes. Mounting hardware is included for installation.

Does this water neck swivel?
Yes. The swivel design allows the outlet to be rotated, making it easier to align the upper radiator hose for a cleaner installation and improved routing flexibility.

Does this include a heater bypass provision?
No. This water neck does not include a heater bypass provision.

Does this fit LS engines?
No. This water neck is built for Chevy Gen I small block and Gen II/V/VI big block thermostat housings — LS-based (Gen III/IV) small block engines use a different housing design and require a different water neck.

Why choose 45° instead of straight, 15°, or 90°?
The 45° angle provides a larger routing offset than straight or 15°, useful when an engine bay component sits close to where a lower-angle neck would position the upper radiator hose. Choice comes down to available clearance and hose routing, not engine fitment.

Will this fit any small block Chevy, or only certain years?
It fits Gen I small block engines from 262 through 400 CID, but thermostat housing bolt patterns can vary by year even within that range — confirm your housing's bolt pattern before ordering.

Is a replacement O-ring available if this one wears out?
Yes. TSP sells a replacement O-ring sized for this swivel-style aluminum water neck family, including this 45° version.

Is this suitable for a restoration build looking for a factory-style appearance?
Yes. The black aluminum finish and swivel outlet suit restoration and classic builds looking for a clean, factory-style appearance at the thermostat housing.