Billet Specialties 90920 - Thermostat Housing -20 An Straight-Out LS Appl

Features:
- Precision Machined from 6061-T6 Billet Aluminum
- Stainless hardware included.
- Available in -16 and -20 sizes.
- Select from Machined or Black Anodized Finish.
- Accepts OEM LS two-piece style thermostat and seal.
- Includes O-Ring for use without a thermostat.
- Includes 2- M6 X1.0 X 16mm stainless socket head cap screws for installation.
- Made in the USA.

The hole diameter in the pump will be 1.875-1.885" (1 - 7/8")

Requires use of the following thermostats:
- AC Delco LS Thermostat P/N 1311056 and P/N 131169 thermostat seal 187 degrees
- Gates Thermostat P/N 34812 (includes seal) 187 degrees
- Stant Thermostat P/N 14948 (includes seal) 187 degrees

Will not fit early water pumps 97-03 that have a one piece thermostat housing. (thermostat is locked into housing with aluminum tabs on each side) The hole diameter in the pump is 2.052" (2 - 1/16") Installing this housing on older style pump will result in leaks.

Fits:
GM LS series water pumps that utilize a separate thermostat and water neck housing
Edelbrock LS Water Pumps