Description: Classic small block power. These GM Performance Parts 350 c.i.d. cast iron racing Bowtie bare engine blocks are CNC-machined from raw castings. All traditional racing modifications are provided by the factory. The heart of these blocks starts with a 3.980-4.155 in. Siamese bore cylinder case. In addition, all galleries required for dry sump oil system operation are drilled and tapped for(more)

Description: Classic small block power. These GM Performance Parts 350 c.i.d. cast iron racing Bowtie bare engine blocks are CNC-machined from raw castings. All traditional racing modifications are provided by the factory. The heart of these blocks starts with a 3.980-4.155 in. Siamese bore cylinder case. In addition, all galleries required for dry sump oil system operation are drilled and tapped for pipe. 8620 steel bearing caps are installed on all locations of the blocks. The intermediate main bearing caps have the outer 7/16 in. diameter studs on the inner locations, and 3/8 in. diameter straight bolts on the outer locations. The rear bearing cap is a 2-stud (7/16 in. diameter) configuration and utilizes a 2-piece rear seal design. After the installation of the steel bearing caps, the blocks are align bored.Additional features include:* Priority main oiling* Enlarged lifter bosses* Bearing cap inner bolts spread .210 in. to allow use of 2.65 in. diameter journal cranks on properly modified blocks* Early model 2-piece rear main seals* Sonic bore check (data provided)* Use 1985 and earlier oil pans* Enlarged cam bosses in front and rear allow use of larger bearings* Use premium quality studs and 8620 200 steel splayed main bearing caps (minimize)