High nickel block

[Shnalla]

Hi guys,

 

I was told my sbc is a nickel nickel block.

Here is a pic of the bell house :

 

Can anyone educate me about casting numbers and high nickel block ?

[Mike G]

Well you don't have a high nickle block. If it was you would have a casting number of 3951509 or 3030817. they were made from 1974 to 1976 and were 400CID 2 Bolt.

 

Your block the 3970010 is a 1968 to 1979 2 or 4-Bolt mains used in truck and hi perf application. This is the one of the most popular blocks GM made. The only way to tell if its a 2 or 4 bolt mains is to pull the pan.

[Shnalla]

Thank you Mike.

My Monte is supposed to be L65 powered... I guess it's a 2 main bolts.

[TrunkMatt]

Only way to check is to remove the timing cover.

 

If your block has the numbers 010/020 under timing cover and in bellhousing area in back it is indeed a high nickel/tin block.

 

010 under the timing cover on its own = 1% more nickel

 

020 = 2 % nickel

 

Both 010 & 020 = 1% tin and 2% Nickel (most desirable)

 

 

Here is a nifty book that can explain everything: http://books.google.com/books?id=AatRNAM...ock&f=false

[72MC]

Your block the 3970010 is a 1968 to 1979 2 or 4-Bolt mains used in truck and hi perf application. This is the one of the most popular blocks GM made. The only way to tell if its a 2 or 4 bolt mains is to pull the pan.

 

Actually, you can tell if the 3970010 is a 2 or 4 bolt main by checking for a small pipe plug fitting at the 11 o'clock position on the front of the block above the timing chain cover(right side/pass side). I believe it is a 1/8 square head pipe fitting and if it is there, the block is a 4 bolt main. If no pipe plup, then the block is a 2 bolt main. - Dave

[Mike G]

Good to know! Thanks Dave.

[Shnalla]

Thank you Dave ! I will check it out.