Just wondering if anyone in here can tell me how to tell which 350 blocks are high nickel content. I've heard that certain blocks from the 70's and 80's are low nickel blocks and prone to grenading, anyone know what blocks these may be?

 

Actually I found the answer rather quickly: "Tin and nickel are two metals that are commonly alloyed with cast iron to improve durability, hardness and heat dissipation. Some production engine blocks have the numbers "010", "020" or both cast into their front face, just above the main bearing bore. (The timing cover must be removed for these numbers to be visible.) If both numbers are present, one about the other, it indicates that the block alloy contains 10% tin and 20% nickel. A single number, either a "010" or "020" represents the amount of nickel and indicates negligible amounts of tin. No numbers, other than the casting numbers that are typically found beneath the timing cover, translates to only minor amounts of tin and nickel being present in the block alloy" So lets change the question a little, are our L98 and Lb9 TPI blocks high nickel? Or does it vary?

 

i have a 010 4bolt shortblock in my backyard

 

I have a 020 4 bolt 305 in my Van.

 

I would guess it wouldn't be 10-20% nickel, closer to 1% or .1%...

i'm guessing the l98 and lb9 are not high nickel blocks. just my guess.

 

Supposedly it's .1% and .2%.

There has been some debate as to whether those numbers actually indicate the nickel content in the block.

 

In the grand scheme of things, it's pretty insignificant. Magazine article fodder mostly.

I'd be more worried about if the crank bore was straight, if the decks were parallel to that and true, if the bores weren't already either used up or thin or porous, if the lifter bores point at the cam correctly, if it's equipped for roller stuff if I was using that, if the starter blot holes are in the right place, if there's cracks in any of the usual and most obvious places, how much core shift there was around the cam and the main webbing, how thick the main webbing is, how much rust there is in everything, how well cared for the motor that it came from had received (like was it full of oil ash from overheating), etc. etc. etc.

Then and only then, once I had narrowed my pile of blocks down to only those with all of those other characteristics meeting my standards, from those I might possibly pick the one with the highest those numbers.

I sure wouldn't consider that to be the most important, or the first or even near the first, criterion for selecting a block.

Alot of 70s and 80s blocks had that metallurgy. It has nothing whatsoever to do with "grenading". It has more to do with the stability of the casting vs temperature.... i.e. resistance to warping from overheating. One typically finds those in truck applications.

 

theres some info pages on this all over the place

http://www.mortec.com/locatpg2.htm
"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."


http://www.nastyz28.com/faq/engine.htm
"Q: What is a Bowtie, or heavy duty (nickle) block and do I have one?

A: Tin and nickel are two metals that are commonly alloyed with cast iron to improve durability, hardness and heat dissipation. Some production engine blocks have the numbers "010", "020" or both cast into their front face, just above the main bearing bore. (The timing cover must be removed for these numbers to be visible.) If both numbers are present, one about the other, it indicates that the block alloy contains 10% tin and 20% nickel. A single number, either a "010" or "020" represents the amount of nickel and indicates negligible amounts of tin. No numbers, other than the casting numbers that are typically found beneath the timing cover, translates to only minor amounts of tin and nickel being present in the block alloy.

However, cylinder wall thickness is the overridering consideration - and a block with no tin or nickel and thick cylinder walls is generally preferable to a high nickel block with thin walls."

http://www.google.com/search?num=20&...020+tin+nickel

 

To add some more food for thought:

http://www.nastyz28.com/forum/showthread.php?t=10896

 

Very interesting, ape....

Goes a long way toward explaining why there's no detectable difference in the actual finished product (the engine) and how hard it runs or how long it lasts, according to whether the block has those numbers or not. Like the guy said, it's more about "brag".

 

Thanks for the input guys, very interesting info to be found here!