[MikeNoun]

I have a customer with a 1971 Judge that is asking some very specific questions about block and head castings. I researched PY threads on this topic and found some interesting information, but I was wondering if anyone has any more insight as to date codes and casting numbers for the 455HO heads and blocks.

This is a 2nd week Feb 1971 build.

I believe the correct block is 485428, but still not certain if there was a specific week where the plant changed over from the earlier 483677 block.

And is there a definitive answer to the 197 vs 191 head casting controversy? I see reference sites where the 191 is listed, others where they state the 191 is an error and were actually 197 but the 7 was an odd font.

References show:

191 (Round Port) 1971 455 HO, 335 hp, 2.11 / 1.77 111 cc, screw in studs

-or-

197 (191) (Round Ports) 1971 455 HO, 335hp, 2.11/1.77 111 cc

-or-

(191) 1971 455 HO, 335 hp 2.11/1.77 111
(197) 1971 455 HO, 335 hp 2.11/1.77 111

Were there specific dates when they used 191's vs 197's?

Thanks in advance,

Mike

[Judge273]

Not sure on the 191vs 197 head thing? Thought all were 197?

But, I do know early heads didn't have cast dates. Later in year did...a 2/71 should have dates that predate block.

[johnta1]

They are 197 codes, but some had the last digit not well formed and is mistook as a '1'.

That's why usually some are reported as '191' heads.

The Feb. Judge more than likely had the 485428 block.
He doesn't have the original block?
If so what is the casting number?

Also what is the date code on the block, which would help determine the block code easier.

[MikeNoun]

John, thanks for the info.

I'll find out more about which block and heads are on the car. I was originally just trying to figure out the 191/197 head casting thing because so many sources show both codes.

Mike

['ol Pinion head]

485428 casting block.

DATED, I.E; L080 & A081 197 casting date heads.

IF the engine was original to a Feb '71 assembled Lakewood A-body or a Norwood F-body, the likelyhood of the original engine having non dated (early style casting) 197 heads would almost be a certainty.

[poncho-mike]

I have two Feb dated YE blocks, and both are 485428 blocks.

As noted, early heads had the cast date inside the valve cover, which was mostly removed by machining the valve seats. I don't know when the cutover changed, but there was only one p/n for the 1971 455HO head.

The image below is of what I think is an early head. The 1 and 7 look very similar, but I think the top piece of the 7 is slightly longer than the 1.

[poncho-mike]

For some reason, this image refuses to rotate 90 degrees, even when the source file is rotated.