Block Wear Characteristics

[A. G. Olphart]

GM obviously knows how to cast a decent block (the old 010/020 marked blocks) but the run of the mill castings seem to wear like crazy. So far I've not found a good old style block, so now I'm considering using a newer one.

 

How do the one piece seal blocks hold up for ring wear? Is there a marking system for the new blocks to show when better/2% nickel iron is used?

 

Sure wish Grumpyvette was still around... not that I don't like the rest of you

I wonder if all the hurricanes washed him away? Has anyone heard?

[Guest zfan]

I too second that..where oh where art thou Grumpy

 

Mike

[jt1]

I don't think any of the two piece seal blocks are high nickel, I've never even heard it mentioned.

 

Right now I'm using a mid 80's 4 bolt two piece mexican block, which seems to be pretty decent. Wall thicknesses were pretty good and it doesn't seem to wear much.

 

John

[A. G. Olphart]

Hey guys, are there no automotive machinists or GM mechanics among you who can satisfy my/(our?) curiosity about the one piece seal blocks?

 

How do they seem to hold up after 200,000 miles - like Toyota/Nissan, or still the same old GM block in need of a bore job?

 

Any and all info appreciated. TIA.

 

 

And here's a thread on the early blocks...

http://hybridz.org/nuke/index.php?name=PNphpBB2&file=viewtopic&t=3150&highlight=010+020

 

Hope it works.

[dr_hunt]

Ok, the days of heavy duty are behind us now in the automobile industry. It's all bout high production, low cost. Most of the cast iron in use today is comprised of recycled iron. To get a high nickel block you have to look at World or Dart. I have one Dart block and 10 early 350 and 400 4 bolt blocks. Cylinder bore wear is a factor of many things, including intake air quality(ie. air cleaner), piston skirt thrust which is a function of rod angle, cyhlinder pressure and rpm. And last but not least oil change interval (most important).

 

Picture this, you start with a world or dart block at 4.00 inch bore, run it for 100K, bore it .030, assuming you changed oil regularly, run it another 100K, bore it .060, run it another 100K, bore it .125, run it another 100K, bore it .155, run it another 100K, bore it .185 run it another 100K. That's 600K miles and you have CNC machined to tight tolerance, priority oiling, clearanced for big crank, 4 bolt mains on all 5 caps, blind tapped head bolt holes, designed for 1500 HP and the list goes on for $1900.

[DavyZ]

I can totally see your point...it's just the relatively painful $1900 + shipping and any taxes that hurts. Shoot, the block is nearly twice what I payed for the whole car

 

Davy

[A. G. Olphart]

Yup, the aftermarket stuff is several multiples of a used stock block plus local machining... I'm not a bucks up kind of guy. (If anyone wants volunteer the resources, I wouldn't mind experimenting with the lifestyle).

 

I did visit a bit with a local machinist last night; he works days at a Japanese engine emporium, so he's familiar with engines from both sides of the pond. In his opinion GM castings are still not up to Nissan/Toyota's level.

[blueovalz]

Don't ask me to provide a link, but I've read serveral sources stating the metal temperature has an effect on wear characteristics. In a nutshell, the higher temperatures promote less wear. The implication was a colder running motor has a higher cylinder wall wear than the same block running at a higher temperature.

[A. G. Olphart]

Certainly metallurgy is far from the only factor in wear, but it is a very significant one.

 

 

Smokey used to like evenly cooled warm/hot running engines, and it makes a twisted sort of sense anything he liked would wear less too.