L31
- Thread starter Dustytrix
- Start date
I assume your referring to the late sbc roller cam vortec blocks, with the taller lifter bores and one piece rear seals?
http://www.sallee-chevrolet.com/Engine_Blocks/gm.cfm
10105123 10105123 350ci Bare Block
This engine block is used in 1986-99 Gen I heavy-duty applications. It has 4.00" diameter 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.) These blocks weigh 181lbs.
http://www.summitracing.com/parts/CLO-9-1157/
this block requires a single roller timing chain for clearance, the one above
Technical Notes: Cylinder wall thickness is the same as current production engines. The lifter valley is machined for hydraulic roller and flat tappets. Crankshafts with two-piece seals can be installed with adapter P/N 10051118. (Block casting P/N 10243880 or 14093638.)
viewtopic.php?f=51&t=2371
similar to this
http://www.summitracing.com/parts/SUM-150100/
If you are,theres no reason not to use the L31 or late OEM SBC roller lifter design blocks for a mild performance build, and they do have the advantage of the taller lifter bores so use of the OEM hydraulic roller lifters on low and medium lift roller cams saves a good deal of money over the aftermarket conversion roller lifter kits.
but keep in mind the factory suggested max hp the blocks designed to handle is about 400hp,and the casting is rather thin, compared to the better aftermarket performance blocks, making them a POOR choice if your going top build something outrageously over powered
http://www.2quicknovas.com/vortecheads.html
http://sallee-chevrolet.com/Cylinder_Heads/Vortec.cfm
casting numbers
10239906 and 12558062..96-up...350.........."Vortec 5700", "L31", 64cc chamber,
170cc intake port, 1.94"/1.5" valves
http://www.sallee-chevrolet.com/Engine_Blocks/gm.cfm
10105123 10105123 350ci Bare Block
This engine block is used in 1986-99 Gen I heavy-duty applications. It has 4.00" diameter 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.) These blocks weigh 181lbs.
http://www.summitracing.com/parts/CLO-9-1157/
this block requires a single roller timing chain for clearance, the one above
Technical Notes: Cylinder wall thickness is the same as current production engines. The lifter valley is machined for hydraulic roller and flat tappets. Crankshafts with two-piece seals can be installed with adapter P/N 10051118. (Block casting P/N 10243880 or 14093638.)
viewtopic.php?f=51&t=2371
similar to this
http://www.summitracing.com/parts/SUM-150100/
If you are,theres no reason not to use the L31 or late OEM SBC roller lifter design blocks for a mild performance build, and they do have the advantage of the taller lifter bores so use of the OEM hydraulic roller lifters on low and medium lift roller cams saves a good deal of money over the aftermarket conversion roller lifter kits.
but keep in mind the factory suggested max hp the blocks designed to handle is about 400hp,and the casting is rather thin, compared to the better aftermarket performance blocks, making them a POOR choice if your going top build something outrageously over powered
http://www.2quicknovas.com/vortecheads.html
http://sallee-chevrolet.com/Cylinder_Heads/Vortec.cfm
casting numbers
10239906 and 12558062..96-up...350.........."Vortec 5700", "L31", 64cc chamber,
170cc intake port, 1.94"/1.5" valves