This Chevrolet Performance intake manifold is the NNBS cathedral-port truck design and serves as a factory style replacement for the discontinued TBSS intake. It is a black composite manifold that uses the OEM throttle body flange and fits cathedral-port Gen III and Gen IV LS truck engines.
Specifications:
- Cathedral-port truck intake manifold (NNBS style)
- OEM throttle body flange
- Composite (plastic), black
- Replacement for the discontinued TBSS intake
- Fits GM LS-Series cathedral-port truck engines (Gen III/IV)
- Sold individually (each)
- Part number: 12638038
Applications:
- GM LS 4.8L cathedral-port truck engines (Gen III/IV)
- GM LS 5.3L cathedral-port truck engines (Gen III/IV)
- GM LS 6.0L cathedral-port truck engines (Gen III/IV)
FAQ
What engines does intake 12638038 fit?
It fits GM LS-Series cathedral-port truck engines, including 4.8L, 5.3L, and 6.0L Gen III and Gen IV.
What is it made of?
It is a black composite (plastic) intake manifold.
Does it use a factory throttle body?
Yes. It uses the OEM throttle body flange.
Is this a replacement for the TBSS intake?
Yes. It is the NNBS cathedral-port truck intake that replaces the discontinued TBSS intake.

