Me i'd look for a pair of D2 or D4 heads that have the ford hardened seat 1972-76 trucks only have them. And sell those.

Ha those the block off gaskets that burn out in a short time as, I found out on my engine.
Orich

 

I had this exact issue on my 390. I tested the crap out of everything and it turned out
to be the vacuum advance was "pulling" advance too much. Everyone here can attest
that each FE has it's own sweet spot for timing. My 390 is built somewhat "hot"
so I disconnected vacuum advance and it runs awesome without it. So...I just run
it with no advance.

 

I appreciate the input. The heads are definitely leakers. I ordered a set of completely rebuilt D2 heads with larger valves on ebay. Is it okay to reuse the old head bolts? They look to be in great shape.

 

Yea the bolts can be re-use if they have not been over tightened.
A stock rebuilt you can get by re-using the bolts but yeah don't know what the engine has been through. 40+ yrs a lot can happen to an engine's bolts by some people not using the correct tools like a Torque wrench but just doing it by it's feel.

Saw many guys over the yrs putting an engine back together with using a torque wrench then snap a bolt here & their. And would end up having a leak where they broke the bolt at. The ol backyard shade tree mechanics that can do every thing but doing it right!

Orich

 

The bolts look nearly new. One bolt on each side had a washer under it for some reason.

 

The manual say to tighten the heads in 3 steps until your at 90lbs.

I can't remember off the top of my head what each step lbs but think it was 50 lbs for the first tightening. But It's been a few yrs since putting on heads so check your manual for each poundage pull.
Orich

 

30, 60, 90 will work just fine. Don't forget to clean the bolt and block threads and oil the bolt threads.

 

The new heads will arrive next week, so I am cleaning, cleaning, cleaning..... I have been wiping down the block with acetone, but at this rate it will never get clean. Can I be more aggressive? The top of the pistons have some carbon deposits that start to come clean with the acetone. I have read about using brake cleaner, 80 grit sandpaper on a long sander, grease in the bores to collect the dust, etc. What is the best way? Thanks.

 

As all long as you don't scratch the top of the pistons. I've use brass wire wheel on a hand drill.

I have used diesel on stuck build up of carbon help loosen it. Sometime you can use a good putty knife work off the built up of it.

Acetone is really good for wiping off the surface before applying gaskets it dry's to fast.
Orich

 

If you use a putty knife, use a plastic one.

 

Got the heads installed and painted black (they came blue). Started taking a closer look at the lifters. None of the lifters are dished, but they are all flat. They should be convex? Can I assume that the cam is similarly worn? Thanks.

 

Ok. New heads are installed, as well as a new cam and lifters. I have a pushrod checker, and a 12" digital caliper. I have the engine at TDC, which should allow me to check 1, 3, 7, 8 intake, and 1, 4, 5, 8 exhaust. #4 & 5 exhaust, and #7 & 8 intake lifters are not all the way down in the bores. Do I just rotate each lifter until it bottoms out, then check for pushrod length, or am I missing something? Timing chain is installed straight up. Thanks.