This engine block is used in 1986-99 Gen I heavy-duty applications. It has 4.005" diameter finished cylinder bores and four-bolt main bearing caps. This block is machined for a one-piece rear crankshaft seal. (Does not include rear seal or adaptor.) This block has machined oil pan rails to clear the 3.800" stroker crank (see below) used to create the GM 383 crate engine. This block weighs 181lbs.
Technical Notes: Cylinder wall thickness is the same as current production engines. The lifter valley is machined for hydraulic roller and flat tappets.

Installation Notes:

• GM 383 Crate Engine Crankshaft 809-12489436
• GM 383 Crate Engine Piston 809-88962748
• Bearing Kit 809-17800761
• Connecting Rod 809-19169670

Note:

• Crankshafts with 2-piece seals can be installed with 809-10051118 Adapter

19433406 supersedes 19432109, 88962516

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

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