308 aluminum head

[Deleted User]

Hello, I have a couple of aluminum 308 heads. In doing some reading on this forum they have to be over "1.94" thick. What was the original thickness of the head, and is the measurement from the bottom of the head to the top of the stud holes? I want to make sure I am measuring correctly. I will attach a photo of the measurement if I can. Thanks for the help

RL Chilton

It is my understanding that the head you have is basically wall art. The head started life as 2.000" thick, and yes, you are measuring it correctly. Maximum size to be milled is .060", which would mean 1.940"

Browniepetersen

I can confirm what Russell is saying. I milled/lapped a head and it measured 1.900. When I installed it, it blew through and we had to start all over again. It is not much fun to clean up a fresh engine when you blow a head into the pistons.....

[Deleted User]

busybee wrote:

Hello, I have a couple of aluminum 308 heads. In doing some reading on this forum they have to be over "1.94" thick. What was the original thickness of the head, and is the measurement from the bottom of the head to the top of the stud holes? I want to make sure I am measuring correctly. I will attach a photo of the measurement if I can. Thanks for the help

That's real close...



I would double check the calipers and make sure they were zeroed or even try a different set to be sure. Then again I'm no machinist, with the roughness of the top of the head it's got to be tough to get an accurate measurement... so you may have to err on the safe side and scrap that head

[Deleted User]

Thanks for the info, I measured in a couple of places they all come about the same. I guess the recycler's will get twenty more pounds of aluminum to make into cans. From other posts it seems these heads were not real reliable anyway.

Browniepetersen

After inspecting 4 of those heads I gave up and went with the steel head. I could "hog" it out, machine and lap it and still have extra material to work with. It was the best for me in the long run.

Aaron D. IL

All I know about 'em. They have to 1. not be warped. 2. planed smooth and flat and still be in spec. 3. have to retorqued a few times after installation.

Aaron D. IL

" Best" is the brand name????? Thanks for the tip Hudson308

I've seen some HET veterans saying head seepage is not uncommon and jokingly say "of course it leaks, if it doesn't leak you're out of oil." hehe