Air and Fuel› Intake Manifolds and Components

Precision Turbo

Upper Plenum Adapter

$232.79

SKU: PEP022-1011

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$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
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Moderate — 2–4 hours

Overview

The Precision Turbo PEP022-1011 is an upper plenum adapter designed for 1986-1987 Buick Turbo Regals and 1989 20th Anniversary Turbo Trans Ams. It addresses the airflow distribution issue in the factory upper plenum, which can lead to lean conditions in rear cylinders. Manufactured from cast aluminum and CNC machined, this adapter increases internal volume, potentially supporting more horsepower.
Show original supplier description
The Precision Turbo PEP022-1011 is an upper plenum adapter engineered to resolve airflow distribution issues inherent in the factory plenum of 1986-1987 Buick Turbo Regals and 1989 20th Anniversary Turbo Trans Ams. The stock plenum design can cause uneven airflow, leading to a lean condition in the rear cylinders, especially when power is increased. Constructed from cast aluminum and finished with CNC machining, this adapter features a 70mm opening and a higher internal volume compared to the stock unit. This increased volume contributes to a larger intake manifold capacity, enabling the turbocharged engine to support greater horsepower potential. The PEP022-1011 is a direct bolt-on replacement and is compatible with stock 58mm throttle bodies, ported stock 62mm throttle bodies, and Accufab 65mm or 70mm throttle bodies. The kit includes a new GM upper plenum to intake gasket and all necessary fastener hardware for a straightforward installation. Testing has shown performance improvements, including a 2-3 tenths reduction in 1/4 mile ET and an increase of 2-3 MPH in the 1/4 mile.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandPrecision Turbo
Part NumberPEP022-1011
CategoryAir and Fuel
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Shipping

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