Well, yesterday, I dusted off the valve spring compressor that my girl got me for christmas, and removed an intake valve and exhaust valve from one of the sets of 2.8 heads I have. I was shocked to see "clean" ports! In an old message I read years ago, someone was doing a port job on their 2.8 heads. They compared 2.8, 3.1, and 3.4 heads- and said they were all about the same, with lots of casting flash in the ports, which would hurt the flow #s.

Well, I didn't see any casting flash. The ports looked "free" of any junk metal. Odd. I don't know the year of these heads, but it has the umbrella-type valve seals. My engine ('86) uses o-rings on the valves, so this set has got to be post-86. I wonder if 86-below heads are full of extra metal?

I did have to laugh, though. I compressed an intake valve spring, removed the keepers, and removed the valve. The spring was still stuck on the head, along with the spring retainer. So I tapped downward on the spring, lightly, with a hammer. The spring flew across the basement, along with the seal and retainer, and buried itself in a pile of junk. Oh, that was such a pain to dig through all that dusty/cobwebbed gardening stuff!

These heads are pretty rusted; looks like the guy that gave them to me had left them outside in the rain more than once. The valve stems are rusted where they sat in the ports (I guess the ports filled up with water), and the springs are rusty, and there's no rocker arms. But, looks like the valves are thick enough; they could probably be cut down, and saved as spares. I think I'll make this set of heads into my "porting job test".

 

Hahaha. Nothing funner than looking through a big pile of cob web covered junk to find a spring and a seal.

Well this should be interesting TomP. I expect pictures of course. So how post 86 do you think they are? Maybe we all need a set. minus the rust.

 

It was also at 2:00am-ish in the morning... I was waiting for some shirts to dry for work the next day. I should've just went to bed.

I'm not sure of the year. I think the other set of heads in my basement, the ones I removed from TheWraith's (on thirdgen.org) old 2.8, are from an '87. I'll have to see if I have that old e-mail of his that mentioned the year of the motor. It's somewhat of a shame, though; I expected to see that casting flash, and figured that just by removing it, the heads would flow better. Now it's not as simple of a job anymore. Problem is, with the '87 heads, I never cleaned them. They're full of melted oil (TheWraith's engine blew), and a mess. Yuck. Maybe I'll clean 'em as soon as school's out.

I'm also thinking of getting one of those $30 cheap-o computer cameras. It really sucks having to get pictures developed, and then remembering to scan 'em. Anyone know how good the resolution is on those $60 Pen-Cams? Do they save to .BMP's or web .JPG's?

 

Tom, now you see why I ALWAYS said, it's almost worthless to port these heads.
They are impressively "Clean" compared to old GM heads for a V-8.
Modern Tech is wonderful, so is modern casting methods.
All you need to do is clean, new guides, equal spring pressure, 30/45/60/90 grind, match vavles to new seat, good to go. Really.
How to tell date.
Easy.
Look for this info.
Letter = A Jan, etc.
one two numbers (1-31)
one number= year 5=85, etc.

A155= Jan 15th 85.
COULD BE TRUCK, tho, check valve size.
large valve is MPFI head.

 

Good point; those heads could've been off a truck! Or even an 82-84 motor.. don't know. I'll check that date code (hopefully tonight) and let you guys know! Do you know what side of the head it's on?

 

Tend to be located in the area between cylinders/valves.
Brake cleaner or easy off oven cleaner

 

Well, I guess I missed a number somewhere. There was a number between the valvesprings of two cylinders; it said "GM 14054877"... nothing about any letters. I'll have to check the head again when I get home. Should I not look under the valvecover? Is it stamped on the side?

 

Keep digging, under valve covers.
It's gonna appear!