Nickel in cast iron

I know I mentioned this a few weeks ago. The book I have says Nickel in tke block helps keep the bores true longer and will hold a ring seal longer with less taper.I wish CHP would do some reserch to find out what or if the 10 or 20 really indicates this. This seems to be a theory that no one really has hard facts. I do think it is verry Important in choosing a core for rebuild  If it is true.The book i have had for many years isCHEVROLET SMALL BLOCK INTERCHANGE MANUAL  by David Lewis . It helped me find 2 sb 400s that were sold as 350s to me.  

While the nickel will result in a stronger block which improves alignment and wear qualities, the basic design of the SBC is sufficiently robust that its presence in anything besides a competition block is redundant as the typical inservice loads never come close to taxing the structral limits of the design.

In other words for anything less than full blown competition and perhaps heavy truck duty, the presence of nickel adds a lot of cost but provides nothing to longevity.

Bogie

I agree with your post.  There are plenty of "non-nickel" blocks which have posted impressive power outputs and found their way into the winner's circle.  The inherent design of the 302/327/350 is nearly flawless in all aspects.  I'm amazed how this design has withstood the test of time... these things are +40 years old!

However, the 010 and 020 blocks remain highly coveted and are nearly impossible to find today with their original bore measurements.  While not intending to boast... I was fortunate to find an 010 block (from a 302 Z/28) about 7 years ago for $100 with the original 4.00" bore.

I had a block 3970010 , 1978 it had a 10 and 20 cast into it. It spun a rod bearing because stupid me had the distrubitor too loose and it must of stopped spinning the oil pump. It had never ben apart. When I pulled the heads there was not any ridge at the top of the bore and no taper i could feel. Did not have a dial indicator back then. After keeping it for many years I gave it to a guy for scrap metal. I just had dreams but no money. Or a car to put it in.I like the monte, regal, cutlass cars as they are all the same. It would be enough now to guide someone with money and little knowledge now.  

MY boss made a good point he said too much nickel in a block would wear the rings out so I guess you have to have a compromise to get 100,000 miles out of the rings to hold a good seal.