what year GM block?

[Rambo]

I have what I believe is a 350, with the casting numbers 3GM 395500 on the end of the block. On the side is 509.
I can't find any similiar numbers on any internet sites.
I have another 350 and found it with no problem.
I would prefer to use the 1st one I mentioned , as it is in reasonable and usable condition.
Does anybody have any idea for sure what it is? I don't know the bore or stroke as I don't want to pull it apart.
Thanks
Larry

[clean8485]

I have a reference book here that lists small block casting numbers from 1955 to 1993, and I don't see a match for the number that you're listing. Are you sure that the number is complete? My book does list several casting numbers that begin with 395, but there are 7 digits overall in the complete casting number. Could you have missed a number when you were looking at the block? If you can find any more numbers, please post them, and I'll see if I can find a match for you.

[Rambo]

thanks for your reply. the casting numbers are very clear and that is all there is for numbers 395500, exceot for the side of the block which has 509 casting mark.
I looked for a long time on the internet with no luck. Someone suggested it was a Canadian casting and most of the numbers listed were American etc castings.
I don't know what year the block is. ThaNKS FOR YOUR RESPONSE.
Larry

[dale48mrc]

Okay I'm gonna wade in on this one.The closest number I could find was 3951509 which is a 400 small block from 70 to 80,the first 2 years were 4 bolt main.Where are you finding this number? I always was told the the sbc casting numbers for the block are on the bellhousing flange,on the driver's side.Really double check your numbers ,because I know chevy was real consistent on their casting number placement.

[Fordnutz]

This may be a Canadian pontiac block. They used chev engines, but not sure if they had chev numbers. Pat.

[Rambo]

The numbers are real clear. If I knew how to , I would post a picture on here. I know they are usually 7 number, but this is 395500.
Thanks for trying to help. Tomorrow I am going to pull the valve covers off and check the casting numbers on the heads. They have the small triangle on the end, so I believe they are late 70's.
thanks again.
Larry

[dale48mrc]

Larry,if this indeed is a Canadian block you may have a real hard time finding any info. I have checked every site I know and still haven't found that number anywhere.I have to agree with clean8485, the only numbers I have found that begin with 395 are all 7 digit and none with the six digit casting number.I've played around with SBC's for along time and that is a number I have never seen.

[dale48mrc]

Is this a complete engine? If so,check the flexplate and dampener,if they have counter wieghts on them then you have a 400.That's what I'm thinking you have.

[Techhead]

The numbers are real clear. If I knew how to , I would post a picture on here. thanks again.
Larry

Larry,
send the pictures to techhead.ca @ gmail DOT com (remove spaces and use an actual dot) :D I'll post them for ya.


Pontiac did use 6 numbers but your's is not listed HERE (http://www.pontiacpower.net/engcast01.html).
Nother Pontiac Engine Code Site (http://www.ronspontiacpage.com/reference-pages/enginecodes.htm)

[clean8485]

Just as an additional bit of info, the reference book that I have does list some casting numbers with 6 digits, and it also lists some casting numbers with 8 digits, but none of the 6 or 8 digit numbers begin with 395 or end with 500. Hope that you find out what it is-if you do, let us know.

[Rambo]

I'll try and get a picture today and forward it . Thanks for all the help. I'll check the heads as well and see if I can cross reference for a date. There is no flex plate, I'll check the front counter weight /damper for counter weights.
Thanks
Larry

[Rambo]

Thanks for all the help. I sprayed white paint on the block and sanded the raised area, and one of my 0's is a 9 and there is a 1 betweenthe 5's. hardly legible, but that gives me 3951509, which turns out to be a1974 to 1976 400.
Many thanks..sorry for all the confusion. I t wasn't possible to really see the missing and different numbers even though I sanded the area, till i used paint.
Thanks to all again.
Larry

[clean8485]

Glad you were able to get it figured out. It should make an interesting starting point for an engine project.

[dale48mrc]

That's what I said it would be! Kinda figured you were dealing with a 400. Rambo are you should pull the pan and check the bottom end,some of those were 4 bolt main. You can make some good power outta those,you are just limited when it comes to boring . If I remember correctly 30 thou is max.! That's because of the siamesed cylinder bores in those blocks.30 thou will give 406 cubes and I've seen some of those engines pull some serious numbers.Another scenario for those engines,drop in a 350 crank and end up with 377 cubes.Do some reseach,you'll be surprised what that motor can do!

[34ford]

#3951509 is 400cid 2 bolt mains 1973-1980 :eek:

[larry d]

try mortec.com they have a very good selection of all c/numbers for small and bb chev engines