LS Throttle Bodies – What You Need to Know

GM used several styles of throttle bodies across the LS engine lineup, and knowing the differences matters when building or swapping.

Key Differences:

• Early cable driven LS throttle bodies use a separate IAC (idle air control) valve to manage idle airflow.
• These are known as DBC (Drive-By-Cable) throttle bodies, which are mechanically operated with a throttle cable. These used a 3 pin TPS (throttle position sensor).
• Later models are DBW (Drive-By-Wire) which are electronically controlled. These do not have an IAC valve. Early DBW throttle bodies still used a separate 6 pin throttle position sensor, that was not used on late model throttle bodies.
• These DBW throttle bodies came with either an 8 pin wire connector on early models and later switched to a 6 pin connector.
• Coolant lines on the bottom of early style throttle bodies are designed to prevent icing in cold climates. In warmer areas, they’re often bypassed. Later model engines did away with the coolant lines entirely.

Bolt Pattern:

There are 3 bolt patterns used on LS engines. Starting in 1997 the Corvette debuted with a 3 bolt throttle body. Later the 2005 Pontiac Grand Prix came out with the LS4 engine that had a unique bolt pattern throttle body. Later all LS engines moved to the standard 4 bolt pattern that all modern LS engines used. See the below chart to find the part number needed to change the bolt pattern of your throttle body.

• 3-bolt = old style (e.g., LS1, LS6) – all use the same bolt pattern.
• 4-bolt = LS4 only – Unique bolt pattern is unlike any other LS engine.
• 4-bolt = new style (e.g., LS2, LS3, LS7, Gen 4+) – all use the same bolt pattern.

Throttle Blade Sizes vary by vehicle, and aftermarket options such as Nick Williams go over 102mm. These are available in our store. See the chart below for factory blade sizes used across different models.

Wiring:

Do you need to swap or move your throttle body? We have all the options you need.

Why It Matters for Your Swap:

You have options. Just because your intake is 3-bolt doesn’t mean you’re stuck with an old throttle body. ICT Billet makes adapters, spacers, and harness extensions to mix and match throttle bodies and intakes across generations. See the below chart to find which adapter is correct for your build. Just match the column for your intake and the column for your throttle body, to find the part number needed.

Bottom Line:

No one offers more LS swap parts or combinations than ICT Billet. We stock every adapter, bracket, and fitting you could need, no matter what intake or throttle body combination you are running. Whether mechanical or electronic, 3 bolt or 4 bolt, we have the parts to make it work. Our lineup is the most complete in the industry, period. When it comes to LS swaps, there is no comparison.