66 Engine casting ID

[Richard E.]

Were does one find the casting "ID" number (3 digit) on the engine block? I have a engine with casting number 3858174 which is a 64-67, 327ci, 2 bolt main (as I'm told). I also understand that this could be a truck, Camaro, or Corvette block depending on the casting ID such as #114, #515, #516, #517 etc. The engine is in a car and I'm not sure where to look for this 3 digit number (assuming it's visible at all). Appreciate all responses. Thanks.
Rich

[Lynn H.]

Re: 66 Engine casting ID

I am guessing the codes you mention would be either under the timing cover, and or the bellhousing. I did not know you could discern the actual application of the block by a number, like you mention.
What is the code on the stamp pad (assuming there is one), I would think this is the best method of identifying exactly what application it was originally used in. If you had this (two letter code), I could most likely let you know where it came from. This block was only used in Corvette applications in 1966 so the casting date could help you also.
Lynn

[Richard E.]

Re: 66 Engine casting ID

Lynn,
I had never heard of a 3 digit engine casting code that could determine application either. Possibly my interpretation is in error. I found out about this at http://muscle-car-resto.com, when I typed in the the casting number on their website. A small chart displayed that listed these 3 digit numbers with the application correlation.

The pad appears clean, no obvious stamping. I will investigate the casting date next chance I get. Thanks for responding.
Rich

[Joe L.]

Re: 66 Engine casting ID

Lynn,
I had never heard of a 3 digit engine casting code that could determine application either. Possibly my interpretation is in error. I found out about this at http://muscle-car-resto.com, when I typed in the the casting number on their website. A small chart displayed that listed these 3 digit numbers with the application correlation.

The pad appears clean, no obvious stamping. I will investigate the casting date next chance I get. Thanks for responding.
Rich

Rich------


There is no way I know of to identify application or original usage from any CAST-IN numbers on any block, the 1966-only GM #3858174 included.

By the way, ALL 327 blocks were originally 2 bolt main blocks. GM never made a 327 with four bolt mains. The only small blocks with ORIGINAL 4 bolt main configuration were 1969 302 (Z-28), some 1969+ 350's and some 1970+ 400's.

As far as Corvettes go, the only small blocks with 4 bolt mains were all 1969-70 350's, all 1970-72 LT-1, all 1973-80 L-82, 1992-96 LT1, and 1996 LT4. Some 1994-96 LT1 may not have 4 bolt mains, though.

[Lynn H.]

Re: 66 Engine casting ID

My earlier post should have stated 66 corvette application, not 67 I have corrected it. Meant to say 66. I checked out the link at the website you provided and see what you are referring to, but this would be news to me. I have seen 010 on the outside of some 3970010 350 blocks, as well as under the timing cover. I have seen 870 in the same place on the 870 blocks, but this casting ID they refer to is something I am not familiar with, and have never seen. Thanks for the lead on this website though, looks like it may be helpful for some applications. I looked, but cannot find anywhere to contact them to ask about this information they provide on the 3858174 block.
Lynn

[Wayne M.]

Re: 66 Engine casting ID

Lynn -- could this be the 3-digit code that you're referring to ? -- that is, the "721", which I have no idea what it signifies. The block is a 174 block (early prod.) July 23rd, 1965, which may have some bearing on the G26 that is also cast under the timing cover.

[Richard E.]

Re: 66 Engine casting ID

Joe, Wayne, Lynn;
Thank you for looking into this further. The possibility of a 3-digit casting code which can determine application is interesting even though a long shot. I'll keep researching also and will post any new findings.
Rich

[Mark G.]

Re: 66 Engine casting ID

Guys -

Most of the small block engine castings made at Chevrolet Saginaw Grey Iron went to Chevrolet Flint Engine Assembly. The engines were built to production schedules, stamped with a date, engine code, and engine code sticker. They were shipped to the respective assembly plants.
The cast numbers in the front and rear housings are the last three digits of the part number. The "G' front housing and "H" rear housing core could be used for those blocks. The G26 is the core cavity number from which the sand core was made. The pattern number is next to the "GM" on top and on the fuel pump flange on the bottom of the block.

Mark

[John H.]

Re: 66 Engine casting ID

The pattern number is next to the "GM" on top and on the fuel pump flange on the bottom of the block.

Mark

Mark -

Here's the one on the fuel pump flange.

[Lynn H.]

Re: 66 Engine casting ID

Lynn -- could this be the 3-digit code that you're referring to ? -- that is, the "721", which I have no idea what it signifies. The block is a 174 block (early prod.) July 23rd, 1965, which may have some bearing on the G26 that is also cast under the timing cover.

The website at muscle-car resto.com given above has a casting ID link that states the following:
casting id casting number casting cid hp year deck/maincaps info
114 3858174 327 64-67 normal/2bolt sm journal
515 3858174 327 64-67 normal/2bolt Truck
516 3858174 327 66 normal/2bolt Corvette
517 3858174 350 67 normal/2bolt Camaro

It is the 3 digit numbers in the far left column on this chart that is the topic of original post in this thread. I have NEVER seen any ID numbers like this on a block, and would be interested in any information anyone might have on this. I haven't looked it up as of yet. but did they make a 350 CID motor with this casting number?
Lynn

[Cecil L.]

Re: 66 Engine casting ID

Guys -

Most of the small block engine castings made at Chevrolet Saginaw Grey Iron went to Chevrolet Flint Engine Assembly. The engines were built to production schedules, stamped with a date, engine code, and engine code sticker. They were shipped to the respective assembly plants.
The cast numbers in the front and rear housings are the last three digits of the part number. The "G' front housing and "H" rear housing core could be used for those blocks. The G26 is the core cavity number from which the sand core was made. The pattern number is next to the "GM" on top and on the fuel pump flange on the bottom of the block.

Mark

Mark,
That is great info. What is the source of that page and do you have any more? I'm particularly interested in 58-62 and anthing on 348-409 castings.

[Cecil L.]

Re: 66 Engine casting ID

I'm guessing those 3 digits are just their own list reference numbers and have nothing to do with casting numbers on the block.

[Joe L.]

Re: 66 Engine casting ID

The website at muscle-car resto.com given above has a casting ID link that states the following:
casting id casting number casting cid hp year deck/maincaps info
114 3858174 327 64-67 normal/2bolt sm journal
515 3858174 327 64-67 normal/2bolt Truck
516 3858174 327 66 normal/2bolt Corvette
517 3858174 350 67 normal/2bolt Camaro

It is the 3 digit numbers in the far left column on this chart that is the topic of original post in this thread. I have NEVER seen any ID numbers like this on a block, and would be interested in any information anyone might have on this. I haven't looked it up as of yet. but did they make a 350 CID motor with this casting number?
Lynn

Lynn------


Not that I know of. The 3858174 was a 1966-only block casting. The very first car to receive a 350 cid engine was 1967 Camaro SS. It did use the same block as 1967 327's, GM #3892657. Is it possible that some early 1967 Camaros with 350 cid engines used the 3858174 block? Yes, I'd say it's theoretically possible.

[Mark G.]

Re: 66 Engine casting ID

Cecil -

The 348-409 "W" block may have been cast at Grey Iron, I will need part numbers.
Corvette by the Numbers by Al Colvin describes the 3892657 cylinder & case;
"1967 327 300-350HP 2-bolt This block was used for most 1967 small block applications excluding the 283. This block was designed also for the new 350 engine, which was released only in the 1967 Camaro. This block had heavy truck usage as well." The early Z28 302's may have used this case too.

Mark

[Michael W.]

Re: 66 Engine casting ID

The website at muscle-car resto.com given above has a casting ID link that states the following:
casting id casting number casting cid hp year deck/maincaps info
114 3858174 327 64-67 normal/2bolt sm journal
515 3858174 327 64-67 normal/2bolt Truck
516 3858174 327 66 normal/2bolt Corvette
517 3858174 350 67 normal/2bolt Camaro

It is the 3 digit numbers in the far left column on this chart that is the topic of original post in this thread. I have NEVER seen any ID numbers like this on a block, and would be interested in any information anyone might have on this. I haven't looked it up as of yet. but did they make a 350 CID motor with this casting number?
Lynn

For gins and griggles I put in the ubiquitous 3970010 casting number and out popped the following table:

Casting_id Casting_number Casting_cid rated_hp year Deck main_caps Info

149 3970010 302 CID 290 HP 1969Normal 4 Bolt Late 1969 Z/28 Camaro

150 3970010 350 CID 300,350,370 HP 1970 Normal 4 Bolt Main Corvette and late 1969


151 3970010 350 CID 1669 - 80 Normal 2 Or 4 Bolt Mian Truck


522 3970010 350 CID 1969-77 Normal 2 & 4 Bolt Main Pass, Chevelle, Camaro, Nova, Monte

523 3970010 350 CID 270,330 HP 1971 Normal4 Bolt Main Corvette

524 3970010 350 CID200,255 HP 1972 Normal 4 Bolt Main Corvette

Looking at the large number of errors and omissions is this table and being quite certain that there are no such numbers on these blocks, I'm willing to guess that Cecil's statement above is correct and that the mysterious numbers are simply the line numbers from the .xls database the info is drawn from.