58 mm LT1 NOS Throttle Body for the 1994-97 Chevrolet

These instructions must be read and fully understood before beginning installation. Failure to follow these instructions may result in poor performance, vehicle damage, personal injury, or death. If these instructions are not fully understood, installation should not be attempted.
APPLICATIONS: The products contained in this kit are designed to be a high performance replacement for the LT1 throttle body. To achieve maximum performance with the NOS large bore throttle body, Holley recommends the upper manifold be bored out to match the exact millimeter bore of the throttle body.
INSTALLATION: Check and record the voltage of the throttle position sensor. Using a paper clip or pushpin, find the output on the TPS (Blue Wire—5 volts).
1. Disconnect the negative battery terminal.
2. Remove the throttle body air inlet tube and disconnect the two water lines from the under side of the throttle body.
3. Disconnect all vacuum lines, electrical connectors, and throttle and cruise control cables from the throttle body.
4. Remove the 4-10mm throttle body mounting bolts. Slowly remove the throttle body from the intake manifold ensuring that no other connections are hindering removal.
5. Remove the 7 #20 torx head screws from the water crossover manifold on the underside of the O.E. throttle body. Transfer the water crossover manifold and torx screws to the new throttle body.
NOTE: Ensure the throttle is fully seated to the manifold to avoid leaks.
6. Remove the throttle position sensor from the throttle body. Install the throttle position sensor on the new throttle body. Use the existing screws. To ensure proper operation of the new throttle body, you may need to adjust the throttle position sensor to the original voltage that was on the stock throttle body. The OEM is not adjustable. You may have to slot the TPS to properly adjust with a cordless drill and bit.

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