Engine block question
Thread Starter
Racer
Joined: May 2002
Posts: 279
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From: Gig Harbor WA
Engine block question
I was at the machine shop yesterday looking at my motor when one of the guys there showed me a 1966 427 block he had, casting number 942 (forgot to look at the casting date). He said it was a truck block as indicated by a casting in the front of the block that had the word "TRUCK" and then "PASS" directly under it. There were no stamp pad markings. I haven't been able to find in the few books I have or websites a truck 427 block with a 942 casting number. I saw other casting numbers listed for 427s, which also indicated a taller deck height. Can anyone clear this up?
Thanks!
Thanks!
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It is not uncommon for
TRUCK
PASS
HIPERF
to be cast on the same block.
Unlike small blocks, ALL big blocks are machined to be either a 2 or 4bolt block. The registers (that's the gap where the main caps fit) of big blocks are the same width on both 2 and 4bolt blocks. When they are machined at the factory, either a 2 or 4bolt cap is installed, 2 or 4 holes drilled and tapped and machining completed.
It is extremely simple to convert a 2bolt block to 4bolt yourself (of course you first have to round up a set of 4bolt caps). All of the 266 truck blocks were 4bolt only. If you ever run across one, pull the main caps off. Any good machine shop can install and fit these caps to a 2bolt block. I've had this done to a few blocks.
TRUCK
PASS
HIPERF
to be cast on the same block.
Unlike small blocks, ALL big blocks are machined to be either a 2 or 4bolt block. The registers (that's the gap where the main caps fit) of big blocks are the same width on both 2 and 4bolt blocks. When they are machined at the factory, either a 2 or 4bolt cap is installed, 2 or 4 holes drilled and tapped and machining completed.
It is extremely simple to convert a 2bolt block to 4bolt yourself (of course you first have to round up a set of 4bolt caps). All of the 266 truck blocks were 4bolt only. If you ever run across one, pull the main caps off. Any good machine shop can install and fit these caps to a 2bolt block. I've had this done to a few blocks.
