Proflow Engine Block- SB Chev

When building a mild Small-Block performance engine, blocks from Proflow offer strength, accuracy and peace of mind that can't be assured in a rebuilt core. And, unlike so many of the used cores, nearly all of ours feature four-bolt main caps for extra strength. Each cylinder block is machined to production-spec tolerances and is manufactured to the exact specifications of pre-1986 or 1986-and-later engines.

• Main stud kit to suit - ARP-234-5801
• SH1796S cam bearings required

SBC Iron Small Block
Deck Height ..................................................... 9.025"
Bore ..................................................... 4.125" unfinished
Main Bearing Size ..................................................... 350 (2.45") 400 (2.65")
Weight ..................................................... 205 lbs
Largest Recommended Bore ................................…… 4.185"
Camshaft Bearing Diameter ................................…… SBC - 2.00"
Camshaft Position ..........................................……… Standard SBC
Cylinder Wall Thickness, min. ................................…… .275" @ 4.185" bore thrust side
Deck Thickness, min ..........................................……… .675"
Torque Specs - Main Caps 1 - 4 7/16" bolts 65 ft lbs
5 1/2" bolts 100 ft lbs
Material: Iron
Bore & stroke: 4.185” x 3.875” max recommended
Cam bearing bore ID: SBC - 2.00”
Cam bearings: Special coated, grooved, w/3 oil holes (Not included)
Cam Bearing O.S. + .010”, +.020”, +.030”
Cam bearing press: .002”
Cam journal OD: Standard SBC - 1.869”
Cam Plug: 2.375” dia. cup plug
Cylinder Wall Thickness: .275” min @ 4.185” bore
Deck Thickness: .675” min.
Fuel Pump: Mechanical pump provision
Fuel Pump Pushrod: Standard Length
Freeze Plugs: Stock press in
Lifter Bores: SBC .8427” - .8437”
Main bearing size: 2.450” (350) 2.650” (400)
Main bearing bore:
(350) 2.6405 – 2.6415 (400) 2.8405 – 2.8415
Main Cap Bolts: #1 7/16” (2)
#2, #3, #4 7/16” (2) 7/16” splayed (2)
#5 1/2” (2)
Main caps: Ductile Iron - 4 bolt, center 3
Main cap register: Deep stepped register on each side (no need for dowels)
Oil system: Wet Sump - Main Priority Oiling (can use dry sump)
Oil Pump shaft: 350 main = Stock shaft (.481” OD)
400 main = Stock shaft (.425”OD) MUST machine aftermarket shaft
Oil Filter: Standard SBC filter, uses 2 bolt filter adapter
Oil Pan: Standard SBC oil pan
Rear Main Seal 350 main - std seal / 400 main - FelPro# 2909
Serial No. Left front & main caps
Starter: Standard SBC
Stud holes, Head: Blind holes
Timing chain/gears Standard SBC components
Timing Cover: Accepts stock cover
Torque Specs: #1 - 4 7/16” bolts - 65 ft lbs
#5 1/2” bolts - 100 ft lbs
Weight: 205 lbs @ 4.00” bore