[rememberfireball#22]

Ran into a Pontiac expert at a cruise in several days ago and he wanted to show his buddies how much he knew about GTO's. My Goat has the numbers matching 400 H.O. code WS and # 16 heads. My heads were produced same month as car per date code. He proceeded to explain to me that the 16 heads were total junk. The valves were way to small and the studs were press-in. I tried to tell him that the valves were 2.06 intake and 1.72 exhaust, while not huge, were not small either. And it had screw in studs and I know this because I replaced several valve springs a couple years ago, it even still had the stock gridle on top of the rocker arms. But he knew everthing and I just let him talk. By the way, he had never owned a Pontiac. Would some of you please give me your thoughts on the 1968 400 H.O. and the #16 heads. By the way, my best time at Atlanta Dragway was 14.04 at 99 mph with 3::55 gears w/open rear about 12 years ago on street tires. Thanks

[b-man]

2.11/1.77 valves and screw-in rockers studs on all 1968 #16 heads, they’re one of the desirable big valve high-compression 400 heads made from ‘67 through ‘70.

The 1970 small valve (1.96/1.66) #16 heads with press-in studs were used on some medium performance 400 engines. Not a bad head at all, the ports on the small valve heads were essentially the same as on the big valve heads.

The smaller valves, though not as desirable as larger valves, really weren’t a huge detriment to making good horsepower. Keep in mind that all 389 GTO engines and 421 HO big Pontiac engines all came with heads that had 1.92/1.66 valves and press-in studs. These cars more than held their own on the streets and certainly weren’t turds by any means.

[dataway]

I thought the 16s (as I have in my YS engine 68 GTO) are 2.11 and 1.77. You can't really fit anything larger I don't think ... the valves almost touch as it is.

I think all the RA engines used the same 2.11 and 1.77 valve size. I think most #16 heads have 72cc chambers, so good for high compression builds.

Yes they all have screw in studs. (corrected by B-man)

I mean they aren't round port RA heads but they are pretty much a standard Pontiac performance head.

B-Man ... beat me to it.

[rememberfireball#22]

I'm a little confused. When I stated my valves were 2.06/1.72, I was going by a shop manual I have for 68 GTO. I have found that the manual leaves a lot to be desired in other areas also. So is the manual wrong? Do I have 2.11/177 or 2.06/1.72. I hope I got 2.11/1.77. Thanks, Mike

[b-man]

The manual is wrong.

[rememberfireball#22]

Thanks

[thepontiacman]

There is always one in the crowd at events that claims to know everything. Also beware of wrong info in books and manuals.
Glad to see you searched out people here on a Pontiac Forum with experience that can give you the correct info.

Nice looking GTO.

[68gtoMN]

Those guys who walk around claiming to know everything really bother those of us who do! ;-) '68 #16 heads, as mentioned by B-man and others, have the large valves and are a performance head. Torque wins on the street. Pontiac had plenty!

[dataway]

Just checked my manual .. yep it's wrong ... I now remember many years ago when I came across this, when the shop that did the heads mentioned it had 2.11/1.77 .. I was sure I had some super rare exotic experimental Super SD heads Ahhh the days before the internet when you could wonder about a question for weeks.

[Baron Von Zeppelin]

Originally Posted by rememberfireball#22

He proceeded to explain to me that the 16 heads were total junk. The valves were way to small and the studs were press-in.

He confused himself really bad.

On top of what the others already explained - and the other #16 of 1970 -
1968 #16 Heads are basically identical for all practical purposes to the 1969 (#48) and 1970 (#12) RamAir III Heads.
aka Damn Good Factory Heads
Dual Valve Springs - Guide Plates - Screw In Studs - can't fit a dime between Intake & Exhaust valves.

Next time you could pull a reverse stunt on him
Tell him they are 1973 #16 SuperDuty Heads , and see what he knows

[dataway]

I'd just go with "Last night your mom told me #16 heads were great"

[Frank T]

Has Anyone ever cc'd a set of the small valve #16 head chambers vs the #16 large valve chambers? Are they the same? I have a set of small #16 and have been using 72cc (large valve cc spec i found) in SCR/DCR calculations.
Thanks
Frank T

[b-man]

Originally Posted by Frank T

Has Anyone ever cc'd a set of the small valve #16 head chambers vs the #16 large valve chambers? Are they the same? I have a set of small #16 and have been using 72cc (large valve cc spec i found) in SCR/DCR calculations.
Thanks
Frank T

The small valve 1970 #16 heads are 80ccs. Detailed post mentioning it here:https://forums.maxperformanceinc.com...8&postcount=56

[Frank T]

B-Man, thanks for that link! thats exactly what I needed.

[Red Box Rebel]

Nothing wrong with the #16 heads. From many years of owning Pontiacs (+46 years) I have bumped into a fair number of Pontiac people. No one would have turned down a set of '68 #16 heads.

[Half-Inch Stud]

Back in the 1980s I had 3- sets of 1968 16s at once. Ran well. Never owned a small-vlave 1970 16, but seen a set in the 2000s.

Point is those 1968 16s were very-good (great). 1 set had the extra external metal Boss rail as if Air- injection was gonna be added. Well those heads had to go (Sold!).

[Sidponcho]

For 20 years I've been sit on a set of #51 heads. 125cc chambers. Each chamber is basically a 5 gallon bucket with valves installed.

[pokey1]

Put a motor together in 1979 that was in my car until 1998, altho it sat for many years while I was gone working out of state. Never paid to much attention back then what they were other than they had 16 casting numbers on the center exhaust ports. Went to edelbrock heads in the later 90's when going thru the motor again and gave them to my brother to use on his car. He never did get his car together and sold it awhile later. I thought the heads were gone with the car way back then. A month ago I was at his house and seen a set of Pontiac heads sitting in a shed he had and asked him what they were and found out they were my old heads. Had not been touched since I removed them. Got them back from him and was looking at them tonight for casting numbers. Both had the 16 and one had an L137 and the other had an L267. What would this part of the casting number mean? Posting here because I think they may be 1968 Ram air III heads. Thanks for the help in advance.

[Greg Reid]

L is December...so, December 13th and December 26th of '67 were the casting dates for the heads, which would make them '68 heads.
The '16' heads in '68 were used on several different engines. They are considered 'good' hi performance heads but there is nothing super special about them. They came on the base 350hp 400s as well as some of the high output configurations.
No RAIII in '68. The '68 RAII used a different head, '96' that IS special. Round ports for one thing.

[Kenth]

The 1968 RAI engines uses the #31 D-port swirl polished flat valves heads with 1.712" height installed valve springs for the #744 camshaft.