[lugnutx2]

Long story, I'll try and make it short. A half dozen years ago, after test driving a 67 Lemans, I bought it's 326 engine for my GTO roller, I just needed something to make my car easier to work on. The seller wanted to keep the headers and roller rockers that were on the 326, and he would install some OEM rockers back on the 326, I agreed. I installed the 326 with open exhaust into my GTO, and used it to move the car in and out of the shop, probably had 30 minutes run time doing this. When I installed the exhaust system, there was a lot of loud clicking from the DS valve cover. I pulled the cover and discovered that the seller had installed pre 67 rockers that didn't have the squirter holes, well my rockers and valve tips got chewed up pretty badly, that's why I'm taking them to the machine shop. Also the pass head had epoxy that covered up the heads ID #, I chipped it off and it's a "094" casting, while the DS is a "140". My questions are: Will the mismatched heads cause a problem? I bought Elgin RK 535 rockers for a 67 326, so can I also use these on the "094" head? What length push rods should this engine have? Also, the AMES catalog sells 1967 - 77 V8 rocker arms ( except 1967 326 engines) what's up with that? Thanks!

[steve25]

Your kinda screwed I am sorry to say.

The two heads are not the same.
The 140 heads have a bigger valve size both intake and exh and as far as I know without digging deeper later on for you a different chamber size.

The 326 like the 389 and 421 motorsv used a shorter push rod then the 67 1/2 and up motors.

Another thing to look out for with your heads you have is the push rod guide holes.

Since these early heads do not use push rod guide plates if these holes are worn in the head and allow the push rods to rock around too much then consider the head shot.

While late type push rod guide plates could be fitted along with the needed screw in rocker studs it’s a very expensive job in terms of just the labor.

[lugnutx2]

I did some more research, looks like the CC's are the same and difference in valve size is minimal, this engine ran really well before the rocker problem, so if I can't find a match to either head, I'm going to go ahead and run what I have. Thanks!

[Sirrotica]

On any multi cylinder engine you look at each cylinder as one small engine, They all contribute to the power at the shared crankshaft.

If someone hand ported a cylinder head, and got one cylinder flowing a small bit better than one of the other cylinders, does sthat hold back the better cylinder? Absolutely not, the cylinder that flows the lesser amount just doesn't add as much to total power output.

This theroy was proven many years ago when tandem engine drag cars made their debut. Some racers would use whatever engines they had access to. One guy I remember had a flathead V8 ford in the front, and an OHV Cadillac behind it. No matter that the engines were about as mismatched as possible, the two engines together pushed the unlikely combo to very impressive numbers. The engines were coupled together inline, so they were for all intensive purposes a V16 with totally different components, and engineering.

Having 2 heads that are not matched on the same engine will run just fine, it may not be optimum, but the OP isn't racing the car, so every last HP doesn't matter. people drive cars every day with one, or two cylinders down on compression due to mechanical problems, sometimes for years, and many thousands of miles.

[steve25]

He still has the issue of needing early rockers.

[Sirrotica]

Originally Posted by steve25

He still has the issue of needing early rockers.

He can run 2 different length pushrods in the same engine, correct.
After all BBCs run 2 different length pushrods since they were designed, as do fords and many late model GM V6s.

The valve sizes are inconsequential, and the different valve angle in the heads won't come into play unless he would use a cam that was over .450 valve lift. Stock rocker arms are the same part number, 65-79. Pushrod length is the only difference from 66 to 67.

If his rocker arms don't have the holes under the pushrod, they are 1964 or earlier. Starting in 1965-1979 all Pontiac V8s oiled the rockers thru the pushrod. pushrod length changed in 1967 to a longer pushrod due to the cylinder heads being redesigned.

If he only wants the car to move under it's own power the choice is pretty simple. Use the correct length pushrod for the cylinder head, and only use the late style (65 and later) rocker arms on either head. Problem solved.

[b-man]

Your heads are mismatched by casting number only.

140 is from a 1967 326 9.2:1 compression.

094 is from a 1966 326 9.2:1 compression.

Valve size for both heads are the same 1.92”/1.66”.

Rocker arms and pushrods are the same for both engines.

1961 - 1967 early used the same rockers, other than some 1964 and earlier had no spurt hole in the rockers (rocker stud oiling).

1967 late through 1981 used a different rocker than the earlier engines. 1967 low-performance heads (20 degree valve inclination) and high-performance (14 degree) makes things a little confusing because it was a transition year. The different head designs used different rockers and pushrods.

[Sirrotica]

The heads are listed as having different size valves, as well as compression ratios:

094 1.88 intake 1.66 exhaust 8.6 CR

140 1.92 intake 1.64 exhaust 9.2 CR

I'm fairly certain that they aren't identical castings, and machined identically.

Having worked in a Pontiac dealership, the factory was having problems with breaking valve springs in the transition from 1966 to 1967 due to the valves being too short. The springs needed to be taller so they didn't fatigue quickly.

Also since I've attempted to run 1966 valve covers on 67 cylinder heads and the rocker arms will dimple the valve covers as soon as you start it. The valves I believe, have longer stems on them, necessitating the long pushrods to get the valve train geometry correct.

Bart. I'm not sure where you're getting information from 55-64 for the most part of conventional passenger car engines, oiled the rocker through the hollow rocker arm studs. The OEM rocker arms had no oiling spurt holes at the pushrod pivot point. The OP is saying the rocker pivot balls are dry due to the absence of spurt holes without hollow rocker studs to oil them.

Having taken dozens of these cars apart, and making a living working on them I've seen this dry pivot ball happen when people start mixing parts that were never engineered to work together.

That's what I've encountered, I'm not going back and forth to argue about it, I've listed what I know from my experience, feel free to list your experiences with mixing, and matching early to mid 60s valve train parts.

[242177P]

326 heads didn't get a revised valve inclination
angle. The 350 did. And Wallace says they're the
same CR. Same intake. Negligible exhaust.

http://www.wallaceracing.com/head1.htm

[lugnutx2]

Thanks for all the input, it really helps sorting this mess out. So, using the 140 and the 094 on the same engine is OK? Do both heads oil thru the rocker, and not the stud? Do both heads have the same valve angle? Is the Elgin rocker kit RK 535 the correct rockers for both heads? I'm wanting to take these to the machine shop Friday, not sure if the machinist can add any info or not, they build mostly Chevies, Ford engines.

[Sirrotica]

Originally Posted by 242177P

326 heads didn't get a revised valve inclination
angle. The 350 did. And Wallace says they're the
same CR. Same intake. Negligible exhaust.

http://www.wallaceracing.com/head1.htm

You're looking at the generic info for cylinder heads listed by year on that site, it wasn't taken from GM parts books. If you look the head numbers up the specs are different from the generic listing, my stats I posted came off of the Wallace site as per GM part books. Three other sites have the same info with different size valves, as well as .6 difference in compression ratio.

094 head: http://www.wallaceracing.com/cgi-bin/head.cgi

140 head: http://www.wallaceracing.com/headsearch.htm

The valve inclintion is of no consequence, almost every valve in 1967 was longer than the same application in 1966. Along with longer valves to accomodate taller springs the pushrod was longer to keep the valvetrain geometry. I'm certain you're aware of the early model valve spring breakage problem in 67 too, that led to Pontiac TSB addressing the engineering problem...........

I'll let the experts sort it out.............Cya

[steve25]

To the OP, your heads oil thru the push rods so the rockers you run need a oil hole as I guess the previous owner let you find out the hard way.

[steve25]

I don’t have a parts book that goes back that far, but in my search the 094 head is a 66 casting rated at 9.2 compression with a 62 Cc chamber.

The 140 head is a 67 casting rated for that same 9.2 compression.

[b-man]

1963 and 1964 326 heads had 1.88”/1.60” valve sizes, same size valves were used in the common passenger car 389 heads. All the small-valve passenger car heads used rockers that were oiled through the rocker studs, this was the last year for this feature. 1965-1967 326 engines all had 1.92”/1.66” valves, I’ve seen both 1.66” and 1.64” exhaust valve sizes listed but most will refer to the 1.66” size.

1964 was also a transition year, the high-performance 389 Tri-Power and all GTO 389s used the pushrod oiled 9770716 big-valve 1.92”/1.66” heads. The ‘63-‘64 421 HO used the same pushrod oiled 9770716 heads.

Pontiac never made a 1.88”/1.66” valve size head, the 1.88” intake was always paired with a 1.60” exhaust valve.

By 1965 all the heads used the 1.92”/1.66” valves and were all pushrod oiled, the rockers oiling through the studs was left behind in 1964.

My reference materials are the John Angeles and Pete McCarthy Racer’s and High Performance handbook which has an extensive listing of cams, valve sizes, etc.

Also Pete McCarthy Pontiac Musclecar Performance 1955-1979. Compression ratios are listed for every engine among a myriad of pertinent information

Craig Henrickson and Kern Osterstock Pontiac Heavy Duty Parts & Specs for rocker arm interchange, and yes I’m well aware of the 1964 and earlier rockers without the spurt hole. 1965 was the year the intake manifold bolt pattern saw it’s final revision but the rocker arms didn’t change until 1967 which as I already stated was a transition year with two different head designs each requiring their own separate rocker arms and pushrod lengths.

[242177P]

Originally Posted by Sirrotica

The valve inclintion is of no consequence ...

It most definitely is. Pontiac didn't bother making
another piston. In that regard, the 67 head isn't a
problem at all. Valvetrain isn't an insurmountable
issue.

Originally Posted by Sirrotica

I'm certain you're aware of ...

What I don't know could fill a library. Wait. That
didn't come out right.

[lugnutx2]

My local machine shop went to working 4 / 10's, so I missed the boat on taking the heads in this Week, the ends of the valves have damage from not getting any oil, I'll post a picture tonight and hopefully get some opinions as to whether it's cost effective to fix them or not. I just use this engine to get my project roller in and out of the shop, so I don't want to spend a lot of of $$$ on it. Maybe time to find another good running 326-350?

[gtospieg]

I'd say you could have (For Cheap) a set of the extra heads I have 17's , 47's, 140's(need to be rebuilt) but I'm on the east coast and you're in the mid west so shipping would make that an uneconomical pain in the ass.

[steve25]

Suggestion to the OP.

Instead of sinking money into those heads to use for just short term you might see if you can pick up a set of usable AS IS high comp heads with screw in rocker studs.
This would give you the plus of using stock length push rods , late / common rocker arms and you would also be able to sell them off when your done where as your two 326 heads are not really worth crap!

[lugnutx2]

I thought about that, but not sure which castings, if any would be compatible with the stock 326 small bore and compression ratio, I believe the large valve 1967 and up 350 - 400 heads would require a piston change and the valves would probably hit the block. I do have a set of 1966 093 heads, they came off a 389 block that has been decked .020 - .030 (can't remember which) Anyways, here's what the damage I have. I've decided before I spend any money on the 140's, I'm going to try one more time to find another good running pontiac engine.

[b-man]

The 093 heads would work fine, the compression ratio would be essentially the same as the 140 heads.

In 1964 the 10.5:1 389 engines used the same 345 (845) heads as the 2-barrel 8.6:1 326.