block casting numbers - 2 different ??

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Jun 9, 2011 | 11:02 AM

pusher_sr

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From: ladysmith b.c.

block casting numbers - 2 different ??

after taking off my valve covers, i noticed that there are two different numbers on the heads. is there a separate number (7 digits) for the left side and a "different" one for the right side ? i was wondering if they don't match, do i have a non original head ?

Jun 9, 2011 | 11:10 AM

5thvet

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From: San Clemente CA

The numbers were not different for left and right side. What are the numbers on yours and someone can help with the ID.

Jun 9, 2011 | 01:28 PM

wmf62

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From: Inverness FL

St. Jude Donor '07

Quote:

Originally Posted by 5thvet

The numbers were not different for left and right side. What are the numbers on yours and someone can help with the ID.

the head #s were/are different on my 1970 LT1 crate engine; but don't ask me what they are are, i don't want to take the valve covers off again to see.
Bill

Jun 9, 2011 | 01:49 PM

Mike Ward

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Some years had two or more different head casting numbers running concurrently. Nothing to do with left or right though.

Jun 9, 2011 | 03:13 PM

Blue 396

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From: Horseshoe Bay TX

with Mike

not all that common but not unheard of

Jun 9, 2011 | 04:08 PM

BrettG

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From: Greenwich CT

Check the casting dates for each head, that will be a key piece of information.

Jun 9, 2011 | 05:15 PM

scorpion1110

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From: MD

Quote:

Originally Posted by wmf62

the head #s were/are different on my 1970 LT1 crate engine; but don't ask me what they are are, i don't want to take the valve covers off again to see.
Bill

I'd guess "186" heads or "040" or "041". The 186's are DZ 302 and high horse 350s and I think the 041s were the occasional alternative. I think 040s are high horse truck.

Jun 11, 2011 | 11:16 PM

pusher_sr

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From: ladysmith b.c.

does this head number match ??

here's the number from one of the head's on my 1966-327-300 hp motor. 3890462 with D66. from the research i've done on block casting numbers, i can't seem to find a match. can anyone match this number up with a motor ?
the other head is numbered 3858174 which does match.
thanks. ted

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Jun 11, 2011 | 11:28 PM

vettebuyer6369

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From: About 1100 miles from where I call home.

Either way, "head" numbers are different from "block casting numbers."

Jun 12, 2011 | 01:09 PM

#10

5thvet

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From: San Clemente CA

The 3890462 head was used on 66-68 Camaro/Nova/Chevelle 275HP,
67 Corvette 327, and 67 Z28 with a 302. I couldn't find the 3858174 in any reference I have, Are you sure of that number?

Jun 12, 2011 | 01:18 PM

#11

Mike Ward

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Quote:

Originally Posted by pusher_sr

the other head is numbered 3858174 which does match.
thanks. ted

Maybe 3852174 ?

'63-'64 327 cu/in, 1.72"/1.5" valves.

Jun 12, 2011 | 02:42 PM

#12

65GGvert

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From: Kannapolis NC

3858174 is the BLOCK casting number for 65 66 327. Don't know about the heads.

Jun 12, 2011 | 02:53 PM

#13

JohnZ

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From: Washington Michigan

Quote:

Originally Posted by pusher_sr

Almost all 66's used 3782461 heads, although a few very late 66's used 3890462 heads. 3858174 is the '66 block casting number.

Jun 21, 2011 | 11:53 PM

#14

pusher_sr

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From: ladysmith b.c.

head #'s match with the month ??

Quote:

Originally Posted by JohnZ

Almost all 66's used 3782461 heads, although a few very late 66's used 3890462 heads. 3858174 is the '66 block casting number.

on my small block 327-300 hp., i have the # 3890462 with D66. i'm figuring my car was built in may john, but you are saying the numbers i have came out later in the year. i'm a little bit confused. any more info ? thanks. ted

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