Here are some quick crappy cell phone pics I took of the heads once I got back. What are those tubes in the exhaust ports?
Those tubes are likely the A.I.R. feeds from the air pump. Each head should have a hole in between exhaust ports 5 & 7 with a bolt hole on either side, which fits a pipe from the check valves of the A.I.R. system. Those heads look great, BTW. Should bolt up nicely and work well with your 455.
Interesting, I thought that the smog stuff didn't come around until the 70s. Do all stock heads have AIR tubes like this? Do they affect performance at all? I'm glad the heads look good! It's always a risk buying used. Next step is getting them cleaned and check for cracks.
If the heads are from a 1967 Buick to be sold in California, all of them would have the plumbing for the A.I.R. system as part of the California emissions package. The emissions hardware consisted of the A.I.R. pump, hoses, check valves, PCV valve, air pipe from air cleaner base, and gulp valve for the rear port on the carburetor throttle body. That's it. No EGR valve, no catalytic converter, no carbon canister, etc.
Got it! Thanks for the info, I just did some research and found out that the AIR system was introduced in 1966. Are the AIR tubes in the heads something I should have removed or worry about from a performance standpoint?
No impact on performance. If you're not running the A.I.R. system, just block off the air intake holes.
I used ported big port heads. I did this: 1. TA performance adjustable hybrid hollow pushrods. The rocker cups are larger, thus the hybrid fits. 2. I plugged the oil hole in the block that feeds oil to the capped rocker arm shaft. Left the caps on, no problem. 3. The 67-69 rockers are strong and better ratio than later models. 4. 71-76 pistons have a shorter compression height. Add that to the open chamber later model heads and you'll have no power at all. Bore the 430 to 455 and install 1970 455 pistons if you get them checked for cracks and wear. I built a strong 12 second Buick doing all this with head porting and little c118 Kinney Bell cam. Ran 7.90 in 1/8 mi.
New "stock replacement" 1970 455 pistons are probably sabotaged with low compression height. Real, original 1970 pistons would have to be checked VERY thoroughly for problems including ring-groove wear. Better to get modern pistons, not replacements for "antique" designs.
Wow I completely forgot about this thread! I still have these heads sitting in the garage, but ended up working on the 350 before I swapped it into my Skylark. I still have the 455 block sitting there too. I'm hoping to run across a cheap 1971 Riviera that has no engine one of these days, and use it as an excuse to build the big block!
