440 Six Pack Cylinder Head Bolt Torque Sequence and Specs
The 440 Six Pack or 6-BBL head torque sequence and torque specs for the cylinder head bolts is a question often asked.
Factory 440 Six Pack or 6 Barrel cylinder head bolts are torqued to 70 foot-pounds. The head bolts are torqued in two steps, first 40 ft. lbs. then 70 ft. lbs., while following the torque sequence.
The following diagram is the torque sequence of the cylinder head bolts. The torque sequence starts at the top center of the head and then towards the ends.
The sequence is the same for cast iron, aluminum or other 440 heads.
440 Six Pack Head Bolt Torque Sequence and Torque Specifications
The following step-by-step instructions are from the Chrysler engine manual and used for cast iron Six Pack heads.
Once the cylinder head is placed onto the block, follow these steps:
- Install the cylinder head bolts.
- Starting at the top center, tighten all cylinder head bolts to 40 foot-pounds in sequence.
- Repeat the procedure, tightening all head bolts to 70 foot-pounds in sequence.
Some people prefer using a three step torque sequence, IE: 25-40-70 ft. lbs. or 40-55-70. I prefer to use three steps and take a short break between each step.
It’s a good practice to recheck all the bolts one more time at 70 foot-pounds. You’ll often find a bolt was slightly loose. Also, rechecking will find a bolt you may have skipped during the sequence.
Some people prefer using 70-75 ft. lbs. for the bolts when using a short extension on the torque wrench. I’ve known many people who have success either way. If using factory Six Pack heads, I prefer to use the factory specifications.
Six Pack Aluminum Heads: Specs
The type of aftermarket aluminum heads used can change the torque specifications. Always check with the manufacturer of your particular cylinder head.
Studs or Different Bolt Kits
Using studs or other manufacturer head to block bolt kits on the stock Six Pack head may change the torque specifications. Always check with the manufacturer.
For example, ARP studs may require different foot-pounds done in three steps.
Check out more cylinder head torque sequence articles:
If you have any questions, Six Pack cylinder head torque or more information you’d like to contribute, send us an email found specifically on our contact page.
For the past 40 years, I’ve been studying and researching Mopar engines and cylinder heads like the 440 Six pack. I torqued my first 440 heads 38 years ago while building my first Mopar engine. I’ve read books, articles, magazines, watched videos, attended seminars and spoken to other Mopar experts.
More Mopar Engine Articles!
Article Resources
- Chrysler Engine Service Manuals: 1966-1974
- Wikipedia: Chrysler B engine
- Google Books: Chrysler Engines 1922-1998
- Direct Connection: Vintage Muscle
