Choosing the Correct LS Thermostat Housing

Verifying LS Thermostat Housings

Choosing the Correct LS Thermostat Housing

Don't know which LS AN Thermostat Housing to buy?

AutoPlumb has developed this guide to help you determine which LS Thermostat Housing will fit on your LS water pump.

*Please read this guide in its entirety before ordering your thermostat housing*

For LS swaps with limited space available, refer to our Common LS Configuration

Verify your LS water pump

To ensure you order the correct thermostat housing for your LS water pump, use these center to center measurements to verify the bolt spacing on your water pump.

Differences in Thermostat Housing style

AutoPlumb offers the LS 1 & 2 AN Thermostat Housing in straight, 45°, & 90° in both -16AN & -20AN

The LS 3 AN Thermostat Housing is only available in -16AN & -20AN in the "stock" style.

Modifying the LS 1 & 2 housing to fit a LS 3 pump

If the LS 1 & 2 Thermostat Housing style works better for you (often the case in LS configurations), it is possible to modify the housing plate to fit the LS 3 pump.

To make it fit, elongate the existing countersunk holes to reach the 3.070" bolt spacing. You can then use a washer and longer bolt to secure the housing to the pump.

This modification is done frequently in LS setups with great success.

Mocking up your system

Be sure to use AutoPlumb's Mock Up System to determine the remaining fittings required to convert your system to AN. There are many combinations that may work for your individual system, so take your time during this stage.

Mock Up Instructions

In many cases, LS systems are in fairly tight quarters. AutoPlumb has deigned a configuration that may assist in these cases. You can view the configuration here along with all the templates and fittings it requires.

LS Configurations