I just had my engine fully rebuilt and was told that both of my heads have cracks. Apparently it will cost more to have the fixed then to buy a new set. I was quoted at 50 bux per inch plus he said some other stuff would have to be done after their fixed so i would owe a minimum of 300 bux. My engine is a 69 and i cant find any re-manufactured 68-69 heads so i will most likely be getting ATK re-manufactured 1972-1980 heads. Was their any flow difference between 69 heads and 72 and later due to emissions? Also what modifications do i need to make the the block? I know something need to be plugged but i am not sure what. I know i need the correct rods, lifters, and rockers which i have or can get. Also their is no left and right heads are there? I can just order two heads and be ok?
Just so you know, my opinion is that ATK stands for "About To Knock". Their work is some of the shoddiest I have ever seen. You will have to pay the core charge also, seeing as your heads are cracked, and not considered rebuildable cores. If I were you, I would find a set of used ones and have a local machine shop give them a valve job. Prefferable pre '72, I think the chambers start to get large after that.
The chamber ccs are about 58 cc on all of the 68-80 heads. The 73-80 heads are less likely to crack. There are different head castings, I know of at least 3 main types. 68-72 casting with no coolant scallop in the center. This is likely why they crack most often. 73-76 Most of these heads have coolant scallops in the center and I have never seen one cracked (I have magnufluxed 11 sets for spares) 77-80 I like these since they have the oversized exhaust valves from factory. The only downside to these is the extra smog holes which can be blocked. I am going to get some flow testing done soon on a set of 77 heads and a set of 70 heads to see if there is a difference... I am pretty sure the 77 heads will flow better but I have no proof yet.
Most 68-72 heads are cracked, that is normal... It is not usually a problem though in most cases engines continue for 10 or 15 years without a problem... Then at rebuild time "the heads are cracked".
Yeah i always noticed a slight milky residue around my oil cap, but never saw anything inside the oil. As for ATK i have never dealt with them, but they are selling these CAST # 556, 861, 452, 238 on ebay for 99 each plus 30 shipping all done, valves, springs, everything. No core charge either. Thats the best price ive seen. I have seen others online for roughly 350 a set plus shipping.
I think there is a reason they are so cheep! Consider finding a set locally and having them rebuilt... It does cost $ however the last thig you need is a bad valve job ESPECIALLY since the buick engines have a NON adjustable valvetrain.
Ended up taken them to the machine shop. He showed me the cracks, each head had 2 cracks between 1in and 1 1/4 in long. He is going to fix the cracks, give me a basic valve job, resurface the heads, and assemble them for 450. He checked everything else out and said it would be good to go. For 450 i know the job is getting done right so i cant complain.
Kody....For that 450 your gonna be much happier !! You have good seats, bronze guides and the porting your pop left you ......The right decision !!
