I was told these 305 heads I have may be lightweight castings prone to cracking. If that is the case I do not want to drop money into them, can you guys tell me if they are or not? Thanks...

 

another shot:

 

a casting number might be better than a pic that shows nothing

 

ok, well, the machinist I went to said castings can vary and he doesn't like to do any work on light castings. He said its based off the shape around the outer bolt holes, which is why I showed the picture.

They're 081 castings.

 

Yes those are considered "lightweight" castings.

Looking at the edge of the head below the spark plugs, you can see how they're sort of scalloped inwards in between the cylinders. Heads that aren't "lightweight" are almost straight along that surface. "Lightweight" heads are missing so much material there, they wouldn't seal with alot of the older style head gaskets.

Older "lightweight" heads such as 882s are very prone to cracking; they are very thin in the area between the intake and exhaust valve seats, and crack there; especially when people put 2.02" intake valves in them and then "hog them out". They get REAL thin when you do that.

There are NO centerbolt heads that are not "lightweight".

There is no extra risk of cracking with those particular heads, as long as they aren't ported excessively with big valves installed.

When you talk about "dropping money", what do you propose to have done to them?

 

That's exactly what I was talking about, but now I don't think the machinist will do work on them. He said that he's done work to lightweight castings and had them crack after they went on the engine, so he won't do it anymore.

I won't be dropping much money into them, just a valve job, 1.94 intake, and open up the spring pockets. But, I didn't want to put anything at all into them if they'd be prone to cracking.

 

They are no more prone to cracking than any other late-model (30 years old or newer) head.

People machine on them successfully all the time.

If your machinist won't work on any heads made in the last 30 years, it might be time to find a new machinist, not least because this one is probably due for retirement any day now. Sounds like he might even be older than me.

 

Yeah, he seems real old school, but he's a good guy, knows his stuff and was going to give me a good deal. Plus I know some people that have had him do work and they were happy with it. I wanted a place that I could talk to people that have gone there before.