Had a look again just now, and i can't see any letters. Theres a number (81 or 18) on the driver side heads. On the passengers side i think the whole mounting to the alternator is in the way. See for yourselves, maybe I'm just confusing the location of the casting.



Really appreciate all the input and help I'm getting from this place!

 

Should be on that little flat corner area immediately behind the center of the alternator. If there's nothing there, you've got an older set of heads that predate a roller block. Only way to I'd the older heads is to pull em and look under the intake runners. You can narrow these down some by looking to see what type of rockers they've got. The 77-85 heads will have pedestal rockers (bolt down) and are basically boat anchors with huge chambers. The rail rocker heads were in production from April 66 to the 1976 model year, these have a channel shaped valve end, that centers the rocker on the valve by means of the channel, these are basically useless for a performance engine until you replace the pressed in rocker studs with screw in studs and use guide plates for the pushrods. The pre April 66 heads had the smallest chambers (54 cc) and the best rockers, the rockers were guided by means of a narrow slot in the head that guided the hardened pushrods.

 

The letter you want is on the outside corner of the head as seen in the pic below. I can just see part of the letter on the head in your pick down below the main terminal of the alternator..

 

Wow, you must have good eyes! I still can't seem to find the casting. From your pic Conanski its clear, but not on my engine :S Maybe they put the heads opposite, meaning that the cast is on the rear drivers side?

Photobucket pictures

Took some more shots, maybe you guys with hawk eyes spot something
I really appreciate your help!

 

Yoiu can't reverse the heads so the letter is opposite. Put the pass side head on the drivers side and the letter is in the back corner of the drivers side. Both heads should have the same letter. If not then you've got two different heads on the motor.

 

It's possible what I thought I saw was just a wire or something down behind the alt, and it's also possible the only visible Letter will be at the back of the engine. In my pic you can see the bolt with the copper washer pluging the thermactor hole which means that's the back of the head, the heads are symetrical so it just depends how all the plugs were installed when they were last rebuilt.. the Letter can end up at the front or the back.

 

Yea i figured it does not matter which side you put the heads on as long as you keep them oriented in the right direction so to speak.

Its really cramped by the firewall and i could only get some decent photos with a small camera. I does look like an "S", but it might also say "18/81" again.
I tried to feel the casting, and it felt like an S.
Unfortunatly i cannot cross reference with the other side, since thats even more craped i can't even get a hand in there.

I might just have to live with not knowing which heads are on it until the day I take the engine out...

 

That looks like "GT" to me. Look at the end surface of the head , if they're GT heads, there will be three vertical bars cast into the ends (both ends, so the same bars will be on the drivers side front of the head) A single large "S" denotes E6SE heads. A large "T" will be found on all E7TE heads. "GT" cast here is std GT40 heads. A GTP or P is on the GT40P heads here. These letters are only found on the pasenger side front, or drivers side rear. The opposite corners are bare.

 

Took another shot today with somewhat better results. Worked it in Photoshop to try and clear the image. To me it looks like 13 (this is the head on the passenger sides rear), but number 18/81 appears on the drivers side front. Weird... The back of the driver side seems to be blank just as on the front of the passenger side head.

I can't get a camera down between the firewall and the rear end of the heads to take a clean picture.

Thanks

 

If the pass side front corner and the drivers side rear corner are blank, you've got an earlier set of heads. Pull a valve cover and see what kind of rockers they've got. if they're bolt down pedestal rockers, they're likely D8OE's or E5AE's, both are the same basic head with the big 70 cc chambers. If they're stud mount rail rockers, the only way to tell what they are is to pull the intake and using a mirror, look under the intake runners to read the casting numbers. If they're non rail stud mount, they're C6OE heads or earlier.

 

Okey will do if i get time. For now i have some other issues i have to take care of. Thanks!

And I still don't need any additives to the oil, since it appears that the heads aren't E7TE or anything other we/I assumed?

 

If it's got a roller cam, no additives are needed in the oil. If it's a flat tappet motor, recommending additives is like recommending a religion. Use what you think is best. I'm off flat tappet motors completely.

 

Only time you need any additives in a flat tappet cammed motor is in the first 30 minutes of run time... after that your either good or not.. the cam and lifter made it or they didn't.

all you need is a good old plane Jane oil if it's got a bunch of miles on it.

 

Okey, just thought being older heads would mean a more sensitive cam. Thats why i brought this question up again. The engine runs good with the new oil and filter, so no additives seems to be needed...

The oil pressure at idle is around 50 psi, and at 2500 rpm in drive is around 70 psi (slightly less when warm). Is thats alright?

 

Awesome...