Pontiac Engine Torque Specs

PONTIAC V8 TORQUE SPECIFICATIONS

Classic Pontiac V8 — 265 / 301 / 326 / 350 / 389 / 400 / 421 / 428 / 455 ci
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Read before you pull a wrench These are baseline factory guidelines for the classic Pontiac V8. Final torque depends on the exact parts, block condition, and fastener brand in your build. Torque values assume the listed lubricant — a value is only valid with the lube it was set for. Always tighten in the correct sequence and in 2–3 progressive steps (roughly 1/3, 2/3, then full).
ARP & aftermarket fasteners — do NOT use the factory column If you are running ARP (or any aftermarket) studs/bolts, use that manufacturer's torque value and their specified lubricant (ARP Ultra-Torque or moly). The instruction sheet packed in the box always supersedes this chart. Substituting engine oil for ARP lube changes the required torque. See the Aftermarket section.

1. Bottom End / Rotating Assembly

Fastener / ComponentLubricant / SealerTorque
Main bearing caps (all except rear)Engine oil95 ft-lbs
Rear main capEngine oil120 ft-lbs
Connecting rod bolts — stockAssembly lube45 ft-lbs
Connecting rod bolts — Super Duty (SD)Assembly lube65 ft-lbs
Harmonic damper centerboltThread locker160 ft-lbs
Flexplate (auto) / Flywheel (manual)Thread locker95 ft-lbs
Camshaft thrust plateEngine oil15 ft-lbs
Cam sprocket / timing gear (upper)Thread locker45 ft-lbs
Timing cover to blockEngine oil35 ft-lbs

Rod bolt note: 45 ft-lbs is the factory torque figure. Aftermarket rods and ARP rod bolts are set by bolt stretch — see Aftermarket section.

2. Cylinder Heads & Valvetrain

Fastener / ComponentLubricant / SealerTorque
Cylinder head bolts (cast iron)Engine oil95 ft-lbs
Rocker studs — screw-in, hex headEngine oil55 ft-lbs
Rocker Arm Nuts — Factory Spec from GMAssembly LubeTorqued Down (Not recommended)
Rocker Arm Nuts — Aftermarket and/or Machined/Modified Head or EngineAssembly LubePer Lifter Specification. Typically 1/2 to 3/4 turn past zero lash.
Intake manifold (cast iron heads)Non-hardening sealer40 ft-lbs
Valve coversEngine oil8 ft-lbs
Exhaust manifoldAnti-seize30 ft-lbs
Spark plugs (cast iron heads)None20 ft-lbs

Head bolts: snug in sequence, then torque in steps — ~30 → 60 → 95 ft-lbs following the Pontiac head-bolt pattern.

3. Oiling System

Fastener / ComponentLubricant / SealerTorque
Oil pump-to-rear-main-cap boltEngine oil30 ft-lbs
Oil pump cover / base plate boltsEngine oil*15 ft-lbs
Windage trayEngine oil15 ft-lbs
Oil pan boltsEngine oil12 ft-lbs

Yes — on a Pontiac pump the “cover” is the base plate: the flat plate bolted to the back of the pump body that retains the gears. Those 4 small bolts get 15 ft-lbs. The separate 30 ft-lb bolt is the large fastener that mounts the whole pump to the rear main cap. *Many builders add thread locker (and/or safety-wire) to the cover/base-plate bolts — they are notorious for backing out; an ARP pump-plate bolt kit is a common upgrade.

4. Cooling & Front Cover

Fastener / ComponentLubricant / SealerTorque
Water pump to coverEngine oil10 ft-lbs
Single timing cover-to-intake boltO-ring + light RTV10 ft-lbs

5. Driveline

Fastener / ComponentLubricant / SealerTorque
Clutch pressure plateThread locker25 ft-lbs
Bellhousing (transmission to block)Engine oil40 ft-lbs

6. Aftermarket / ARP Fasteners

The box sheet wins Torque depends on the exact kit, bolt material (8740 / ARP2000 / L19), diameter, and lube. The values below are representative Pontiac-application figures for quick reference only — always confirm against the ARP instruction sheet for your part number. ARP figures assume ARP Ultra-Torque or moly; using engine oil requires a higher torque to reach the same clamp load.
ARP Main Studs — Pontiac 326–455
Fastener / ComponentLubricant / SealerTorque
Main studs — 1/2" (standard positions)ARP Ultra-Torque / moly110 ft-lbs
Main studs — 9/16" (large rear / outer)ARP Ultra-Torque / moly140 ft-lbs
Outer block bolts on 4-bolt caps (if stock GM)Per stock specStock value

After switching from factory bolts to studs, re-check main-bore size/roundness and align-hone if needed.

ARP Head Studs / Head Bolts — Pontiac
Fastener / ComponentLubricant / SealerTorque
Head studs / bolts — cast iron headsARP moly / Ultra-Torque~95 ft-lbs
Head studs / bolts — aluminum headsARP moly + sealer*Per maker (≈90)

Torque in 3–4 steps in the Pontiac sequence. *Use thread sealer on any stud/bolt that enters a water jacket. Aluminum heads are usually backed down slightly and re-torqued per the head/gasket maker (e.g. Edelbrock sheet #61595).

Aftermarket Connecting Rod Bolts — Eagle / Scat / Molnar
Three rules before any rod-bolt number below 1. The bolt sets the spec, not the rod length. A 6.800" and a 6.625" Pontiac rod from the same maker use the same 7/16" bolt — the spec is identical for both lengths. Match by bolt material, under-head length (UHL) and head stamp.

2. Lube is maker-specific and changes the number. Eagle & Scat = ARP moly. Molnar = CMD Extreme Pressure #3 (do NOT use moly or oil on Molnar bolts). A different lube voids the torque value — you must then use stretch.

3. Stretch is the gold standard; torque is the fallback. Use a stretch gauge when the rod allows. Record each bolt's free length; retire any bolt that grows ≥ 0.001". Don't mix methods — use torque OR stretch, not both.
Eagle — 7/16" rod bolts (lube: ARP moly)  •  H-beam Pontiac 6.800" & 6.625"
Bolt material / head stampTorque (ARP moly)Stretch
7/16" ARP 8740 (7/16" head)63 ft-lbs0.0059–0.0063"
7/16" ARP2000 (7/16" head)75 ft-lbs0.0064–0.0068"
7/16" ARP L19 (1/2" head)79 ft-lbs0.0073–0.0077"
Scat — 7/16" rod bolts (lube: ARP moly)  •  Scat publishes max torque, not stretch
Bolt material / sizeMax recommended torque (ARP moly)
7/16" × 1.600" ARP 8740 cap screw63 ft-lbs
7/16" × 1.800" ARP 8740 cap screw63 ft-lbs
7/16" × 1.600" ARP2000 cap screw70 ft-lbs
7/16" × 1.800" SCAT 2000 cap screw63 ft-lbs
7/16" × 1.500" SCAT 2001 cap screw63 ft-lbs

Scat does not list L19 in its standard rod-bolt chart; an L19 special order ships with its own sheet. Verify stretch with a gauge — Scat rods are torqued/honed at the listed value.

Molnar — 7/16" ARP2000 (lube: CMD #3 only)  •  spec keyed to bolt under-head length
Bolt (ARP2000, by under-head length)StretchTorque + Angle
7/16" × 1.600" UHL0.0060–0.0064"30 ft-lbs + 60°
7/16" × 1.800" UHL0.0070–0.0075"30 ft-lbs + 65°

Molnar's standard bolt is ARP2000; read your bolt's head stamp and measure UHL, then use the matching row. L19 and Custom Age 625+ are Molnar upgrade options that ship with their own spec sheet — use that sheet, not this table. Molnar specs assume CMD #3 lube; never substitute oil or moly.

About L19 (every brand) L19 is the strongest of the three (for the highest-output / nitrous / boost builds) but it is corrosion-prone — keep it oiled on the shelf, install promptly, and expect fewer re-use cycles. It typically needs the highest torque/stretch of the set to reach clamp load. Always confirm the exact figure on the bolt maker's sheet for your part number.
ARP Damper / Flexplate / Flywheel
Fastener / ComponentLubricant / SealerTorque
Harmonic damper centerbolt (ARP)ARP lubePer kit (≈160)
Flexplate / flywheel bolts (ARP)ARP lubePer kit (≈95)
Aftermarket Valvetrain
Fastener / ComponentLubricant / SealerTorque
Roller rockers, stud-mount w/ poly-lock (Comp, Crane, Harland Sharp, PRW)Set preload/lash, then jam set screwPer lifter
Shaft-mount rockers (T&D) — stand boltsARP / per maker~25–35 ft-lbs
Screw-in rocker stud conversion (into head)Sealer~50 ft-lbs
Stud girdlePer makerPer maker
Aftermarket Intake & Headers
Fastener / ComponentLubricant / SealerTorque
Aluminum intake on cast iron heads (Edelbrock, etc.)Non-hardening sealer40 ft-lbs
Aluminum intake on aluminum headsNon-hardening sealer~25–30 ft-lbs
Header bolts (Doug's, Hooker, RA, Hedman)Anti-seize / ARP~25–30 ft-lbs

Aluminum intakes torque in sequence to a lower value to avoid distortion. Re-check header bolts after the first heat cycle.

Tightening Principles — Every Job

  1. Clean and chase all threads; blow out blind holes — trapped oil or debris gives a false torque reading.
  2. Match the lubricant the spec assumes. ARP specs assume ARP lube; don't dry-torque an oiled spec.
  3. Torque in 2–3 progressive steps and in the correct factory sequence — never single-pass a head or main.
  4. Use a calibrated wrench; pull smoothly to the click. Re-torque after the first heat cycle where the gasket maker calls for it.
  5. When in doubt, call the pros: (866) 762-7527 or use Ask-a-Tech at butlerperformance.com.
Download printable PDF
Compiled by Butler Performance Inc. — the Pontiac experts. Sources: Butler published spec table and ARP application data.
This chart is a reference aid and does not replace the factory service manual or the instruction sheet supplied with your parts.

Pontiac Engine Torque Specs

These are general guidelines. Final torque ratings may vary and need to be determined based on application and parts used.

Warning!!!    If you are using ARP fasteners, you must use
ARP specs and specified lube. 
Bolts or Parts Lube or Sealer Torque to:

Main Caps

 Engine Oil 95 ft-lbs.

Rear Main Cap

 Engine Oil

120 ft-lbs.
Stock Connecting Rod Bolts Assembly Lube 45 ft-lbs.
SD Connecting Rod Bolts Assembly Lube 65 ft-lbs.

Head Torque Sequence Diagram-Cast Iron

Head Torque Sequence Diagram-Edelbrock

Cylinder Heads

Engine oil

95 ft-lbs.
Rocker Studs (screw-in Hex Head) Engine Oil 55 ft-lbs.

Rocker Arm Nuts
**Factory Spec from GM**

 Assembly Lube

Torqued Down
**Not recommended**
Rocker Arm Nuts
**Aftermarket and/or Machined/Modified Head or Engine**		 Assembly Lube Per Lifter Specification. Typically 1/2 to 3/4 turn past zero lash.
Oil Pump Bolts Engine Oil 30 ft-lbs.
Oil Pump Cover Bolts Engine Oil 15 ft-lbs.
Windage Tray Engine Oil 15 ft-lbs.
Oil Pan Engine Oil 12 ft-lbs.
Camshaft Thrust Plate Engine Oil 15 ft-lbs.

Cam Sprocket/Timing Gear

(upper)

 Thread Locker 45 ft-lbs.
Timing Cover to Block Engine Oil 35 ft-lbs.
Water Pump to Cover Engine Oil 10 ft-lbs.

Single Timing Cover to

Intake bolt

 Install rubber o-ring with light RTV silcone 10 ft-lbs.
Valley Pan Bolts Engine Oil N/A

Intake Manifold

(Cast Iron Heads)

 Non- Hardening Sealer 40 ft-lbs.

Intake Torque Sequence
Valve Cover Engine Oil 8 ft-lbs.
Exhaust Manifold Anti-Seize Lubricant 30 ft-lbs.
Spark Plugs No Lube or Sealer 20 ft-lbs.

Flexplate (Automatic)

Flywheel (Clutch)

 Thread Locker 95 ft-lbs.
Clutch Pressure Plate Thread Locker 25 ft-lbs.

Centerbolt

(Harmonic Damper)

 Thread Locker 160 ft-lbs.

Bellhousing

(Transmission to Block)

 Engine Oil 40 ft-lbs.