Dart Sbc "shp" Iron Engine Block 1-pc Rms; 4.125"-bore New! 31161211l on 2040-parts.com

DART Iron SHP Small Block - Technical Notes

All measurements listed are inches

Part# 31161111 and 31161211

Material: Superior iron alloy

Deck Height ..................................................... 9.025

Bore ..................................................... 4.00 or 4.125 unfinished, 4.165 max recommended

Stroke ..................................................... 3.750 as-shipped (3.875 max recommended will fit with clearancing)

Weight ..................................................... 175 lbs

Camshaft Bearing ................................ SBC - 2.00, Special coated, grooved, w/3 oil holes

Camshaft Position .......................................... Standard SBC

Cam Bearing O.S. ......................................... + .010, +.020, +.030

Cam bearing press ............................................. .002

Cam journal OD ................................................... Standard SBC - 1.869

Cam plug .............................................................press-in 2.106 (2-7/32 is closest)

Cylinder Wall Thickness, min. ................................ .230 @ 4.165 bore

Deck Thickness, min .......................................... .675

Fuel Pump .............................................. Mechanical pump provision

Fuel Pump Pushrod ............................................. Standard Length .500 dia

Lifter Bores ........................................................... SBC .8427 - .8437

Lifters ........... Designed for factory 87-95 Hyd rollers, must use +.300 tall lifters if using link bar lifters

Main Bearing Size ..................................................... 350 (2.45)

Main bearing bore ....................................................... 2.6405-2.6415

Main cap press .......................................................... .005

Main caps .................................................................. Ductile Iron

Main cap register ................................................. Deep stepped register on each side (no need for dowels)

Oil system ...................................................................... Wet Sump - Main Priority Oiling

Oil Pump shaft ......................................................... 350 main = Stock shaft (.481 OD)

Oil Filter ................................................................. Standard SBC filter, requires 2 bolt filter adapter

Oil Pan ............................................................................... Standard 1980-1985 SBC oil pan

Rear Main Seal ................................................................................. 350 main - std 2-pc seal

Serial No. ..................................................................................... Left front & main caps

Starter .......................................................................................... Standard SBC

Head bolt holes, ........................................................................... Blind 7/16

Timing chain/gears ............................... Standard SBC components, will also accommodate 87-95 thrust plate

Timing Cover .............................................. Can use stock cover

Weight ................................................ 175 lbs @ 4.00-bore 165 lbs @ 4.125-bore

Torque Specs ...................................... Main Caps 1 - 5 7/16 bolts 65 ft lbs 2,3,4 outers 3/8 bolts 35 ft lbs

Standard SBC timing chain, timing cover, gear or belt drive can be used.

Actual deck height will be .005- .010 taller for additional machining requirements.

Cam bearing bores should be deburred before installation.

When initially removing main caps, the caps & block should be deburred before reinstalling. This will insure that correct main size is maintained.

Standard SBC head studs or bolts may be used.

Head stud holes are blind. They do not go into the water jacket.

A sealant/antiseize must be used on the head studs. Loctite #620 is recommended.

Studs should never be torqued into block. They should only be lightly snugged.

It is preferred that a bullet be machined on the end of the head stud where it bottoms in the block to center the stud before tightening. .350 OD x .150 Deep

Press-in freeze plugs are available.

Oil pump dowel pins should be .250 OD. Stock GM pins are only .246 OD

This Block should be assembled only by experienced, professional engine builders..

DIPSTICK: Chevy 1980-1985 is required, you will have to cut off the area about 1-inch below the shoulder.

Dipstick Tube installation: If an oil dipstick tube is used, after installation fill, the engine with oil and remark the dipstick indicator Full mark if necessary. In certain applications you may need to modify or bend the tube to properly install it. The tube is a press fit.

LIFTERS

SHP blocks are designed to work with 1987-1995 Factory Hydraulic roller setups. Due to this, if you choose to run a link bar lifter it will require the .300 taller lifters. This is due to the taller lifter boss used for the factory hydraulic roller setup.

OIL PUMP

Std SBC oil pumps are recommended, high volume high pressure oil pumps are NOT recommended.OIL PUMP DRIVESHAFT

Note: Be sure to check distributor to oil pump shaft clearance with distributor, intake manifold and oil pump installed on the block.

OIL PANS

PRIORITY MAIN OIL SYSTEM

Oil is directed to the main bearings first, then to the cam bearings. There are NO provisions for oil restrictors

NOTE: The fuel pump pushrod bore is machined for a .500 rod. Be sure to check the clearance because of the inconsistencies in the diameters of push rods.

NOTE: Due to variations in lifter sizes and clearance preferences, most of our Engine Builder customers prefer the lifter bores sized on the small end of the specification. Sometimes these bores will need to be lightly honed.

SPECIAL NOTE: With a multitude of different crank, rod and piston combinations available it is important to check clearance of all moving parts (especially crankshaft counterweight to block) before attempting any type of assembly.

It is good engine building procedure to ALWAYS check the fit of the distributor before any machining or cleaning is done.

INSPECTION

Upon receiving this block it should be thoroughly inspected for shipping damage.

Prior to machining and assembly please inspect the following items:

Cylinder bores - Oil passages - Deck surfaces - All threads

MEASURING & MACHINING

All initial measuring should be done before any machining has begun.

Decks are CNC machined to standard deck heights. If you need a particular deck height always measure before machining.

Main journals are finish line-honed to the low to middle of the specification.

They should be measured for your preference. If you have need for a different diameter you must realign hone this yourself.

Crankshaft & rod clearance should always be checked before any machining is started. You need .060 clearance for rotating counterweights and rods.

Due to variations in OD dimensions of the numerous lifter manufacturers, lifter bores are finish honed on the tight side of the tolerance to leave room for lifters that are larger than the standard.

WASHING

Final washing should be very thorough, paying particular attention to all oil

galleys. Use hot soapy water and rinse with hot water first, followed by cold water which helps reduces rust.IMPORTANT

Honing Procedures

Hone block to finished size with 220 grit @ 40 amps of load on Sunnen hone.

Make 3 strokes on each cylinder with 280 grit @ 20 amps.

Make 3 strokes on each cylinder with 400 grit @ 20 amps.

When rehoning start with 220 grit, get cylinder straight and round or just deglaze. Then do same procedure as above.

HONING OIL Sunnen MAN 845-55SPEED & FEED CK-10 (C&E) Pulleys

CV-616 185 rpm 50 strokes per minuteHONING 1) Rough .003 rom size Sunnen C30A-25

2) 220 to size Sunnen C30A-55

3) 280 3 strokes Sunnen C30J-65

4) 400 3 strokes Sunnen C30J-85REHONE (deglaze) 1) 220 3 strokes Sunnen C30A-55

2) 280 3 strokes Sunnen C30J-65

3) 400 3 strokes Sunnen C30J-85

RA should be 26 - 28SHOE ASSEMBLY TECHNIQUE

Titanium or hard shoe (part# CK-3570) from Sunnen on one side of honing head.

Delrin (engineering plastic) attached to brass shoe holder & trimmed to size on other side. (Delrin bars can also be purchased from your local plastic supplier)

*** DO NOT use bronze shoe ***

FRESH HONING OIL IS CRITICAL

These are only recommended procedures we have developed through our Pro Stock program. Some engine builders have their own procedures for honing our blocks.

All honing supplies listed from Sunnen Products