YR 350 block

Is the YR block a good block? Or are all 350 blocks the same?  
72 lux. Lemans/custom 350 & 51 chieftain 8

Which casting do you have?
Check the date code too.

1972 350 160/175 HP YR A 8.0 555 7H1 Block Casting # 481990
1973 350 150 HP YR A 7.6 555 46 Block Casting # 488986
1976 350 160 HP (Early) YR A 7.6 254 6X Block Casting # 488986 / 500810

(are you sure it is a 350? - that code shows up for a few engines - 400 & 455 too)

The 76 is supposed to be a weaker casting
I don't remember the exact year or what exactly is weaker about it just what I heard.

Does it have the valve reliefs cut in the block for the intakes?
Without them valve clearance/shrouding with higher lift cams becomes an issue.
For stock it's just fine.

Casting # is on top rear behind pass head deck and the date code is by the vertical main oil galley plug next to the distributor.

The gurus here will know.
I knew once, but then I had teenagers and got stupid.
 
I know, it's not red
~~
How may I serve you?
Boiled, Deep Fried, or Flambe'?

I do know it is a 72 350, had 7H1 heads. Virgin block, original freeze plugs, 555 cam. Motor had 99,464 miles  
72 lux. Lemans/custom 350 & 51 chieftain 8

I do know it is a 72 350, had 7H1 heads. Virgin block, original freeze plugs, 555 cam. Motor had 99,464 miles  
72 lux. Lemans/custom 350 & 51 chieftain 8

Should be a good block, I doubt it will have the chamfers cut for big valves but that's not hard to have done.
Steve  
A little help... 'cause we don't all have to learn the hard way!

How do you tell, and what exactly would have to be done and price guesstimate?  
72 lux. Lemans/custom 350 & 51 chieftain 8

It is for sure the 481990. 160hp  
72 lux. Lemans/custom 350 & 51 chieftain 8

The 69 350HO has chamfers cut for both intake and exhaust valves because they were the only 350's to come with both 2.11/1.77 valves. The 75-77 350's only had intake chamfers because they came with 2.11/1.66. All other 350's came with small valves and did not need the chamfers so I'd guess yours came without them. I haven't had to pay a machinist to cut chamfers but I've heard of guys doing it with a die grinder.
Steve  
A little help... 'cause we don't all have to learn the hard way!

Thanks, sounds like its not to major of a job.  
72 lux. Lemans/custom 350 & 51 chieftain 8

When lookin at block at machine shop, it already had chamfers in it. But machinist knows about the small to large valves and is checking it to make sure it flows right.  
72 lux. Lemans/custom 350 & 51 chieftain 8