nickle content of a chevy block

[iluvmy72]

which casting numbers on those blocks had the high nickle content?

[Hutch]

iluvmy72,
This is what I found on Mortec's web-site:

Some of the smallblock motors used blocks with an additional 1% tin and an additional 2% nickel added to the cast iron alloy. These very desirable blocks can be identified by looking at the block face under the timing chain cover for "010" and "020". These designators can also sometimes be found on the rear face of the block inside the perimeter of the bellhousing mating surface

Hope this helps
Have fun

[67Fleetsidedream]

This is my block number 3970010. Mine has the 010 020 on the front of the block. There are many more out there.

[sgtjed]

i have a 69 350 4bolt block that has the same casting on it.
when it is time to rebuild i gonna make it back into a 350 currently was turned into a 327 by my dad.

[iluvmy72]

I'm confused.....how do you make a 327 out of a 350 block?

[palallin]

Originally posted by iluvmy72
I'm confused.....how do you make a 327 out of a 350 block?

Put in a 327 crank and rods. . . .

[jhow66]

I just gave one of these (010-020) blocks away this evening. (3790010).

[beautimus]

hold on a minute, mortecs info is incomplete on this.
a friend of my dad used to build race motors for a lot of people.
the 010/020 designates a 4 inch bore block. and thats all.
however it was the 71 to 74 4 inch bore with 4 bolt mains
that had the high nickel content.
i have an old copy of hot rod magazine somewhere that talks
about it, also. (god i am an old pack rat. i am the only one i know of that has hot rod magazines from the early seventies that he bought himself.)
anyway you will see the 010/020 designation on a lot of the newer and some of the older 4 inch bore blocks.
its located behind the timing cover. just make sure of the year of the block before you buy one of these "high nickel blocks"
oh by the way some of the later target master 350"s and the bowtie blocks used this same high nickle content.
hope that helps
Tony

[crazy longhorn]

I have a couple of the 10 / 20 blocks in a 2 bolt main(as posted by Hutch, higher tin & nickel). The blocks i usually find with the 10/20 under the chain cover are a 3970010 casting. On some of the later 70s/ early 80s blocks, there was a 010 cast on the lower sides of the block(denotes 4" bore). On the 350 to 327, you can use a 307 crank, & 327 pistons in the 350 block(the rods are all the same 5.7" c to c except the 400 sb @ 5.565). You will find different rod & main journal sizing ( sj or lj), but the late 327(68), & the 307's had the same journal sizes as the 350(as did the 68 & 69 302). crazyL

[sgtjed]

well the way my 350 became a 327 was i had a 69 gmc that had a 327 with a cracked block in it, froze on the po,but very good crank and rods.

my dad had this 350 that he spun the rods in,well being a cheap person that he is,he combined the best parts from the 2 and made a 327 out of the 350. like it has been said the block dosnt matter concerning weather its a 327 or 350 just the pistons rods and cranks.

btw the crank is a forged 327 crank,so he just had it turned 10/10 and rebuilt the 327 using the 350 block. it has been this way since 1985 and is still running good.

[crazy longhorn]

No, it doesnt matter which block you use, as long as they are both large journal. I have done the 350 "destroked" to a 327 in a 4 bolt main block. The LJ 327 & the 350 rods do not differ........just the cranks & pistons(the rods are the same lenght, but the pin height in the pistons are different). to get the proper deck clearance, it take a piston swap crazyL

[Hooter]

what is the exact advantage of having a higher nickle block anyways, bragging rights?

[iluvmy72]

how does the nickle content in the chevy's compare to the Oldsmobile.....I'm told the Oldsmobile have triple that of the best nickle blocks chevy produced.....is there truth to this?

[iluvmy72]

the higher nickle content holds the main bolts better so if there is alot of strain, the engine won't bust a bolt out of the block

[Hooter]

ive built a couple of early 80's 4 bolt mains and I never have seemed to have that problem, the block for my Monte came out of a 79 Van and its now a 383 stroker, rev it up to 6 grand occasionally with no signs of anything wanting to let loose

[beautimus]

i have done the four bolt main 327 thing also. it is a sweet running motor. probably one of the best engines that i have done.
it really didn't need the four bolt mains but , we had the block on hand and the 327 block was worn beyond belief. the cylinder walls were egg shaped. so we tossed it . the crank and rods checked out ok though and the rest is history.

[beautimus]

ILUVMy72

i don't know much about the olds motors, heh heh,
i never messed with those to much, but i wouldn't doubt it,
olds made some stout stuff years ago.
i have played around with pontiacs though. but i never knew much about the metalurgy of the things, ( except the cotton picking cast cranks) i still have a low milage 428 four bolt block that i am haging onto for my next gto (someday).