VCCA Home Forums TECHNICAL - 1945 AND NEWER 1949-1954 Stupid cylinder head question time....

I'm in the process of pulling together that parts needed to rebuild a 1954 235. I read numerous thread stating that the "848" head, beginning in 1956, is the best all-around head to use on the '54-'55 engines when rebuilding these as "drivers" as opposed to numbers-correct for judging purposes. My question is this: is there a cutoff year for this head when used with the '54 rocker setup? I know that the oil delivery setup to the rocker shafts changed beginning with the '59 engine, but I don't know enough about the later 235s to know if there's a cutoff year I need to observe when shopping for a bare cylinder head to avoid oiling problems to '54 the rocker shafts. Can anyone advise me on this?

Thank you very much,

An 848 head will work.

What I did as a young shadetree mechanic back in the late 1950s, before I knew about parts books, part numbers and 2"thick shop manuals was go to a junk yard and find a car with a 235 and pull parts off and see if they would bolt onto my car. In my experiance if they looked the same and bolted on the same, they would work good enough to get me to school or to work and back home and also make the drag on Saturday night, if I had a dollar for five gallons of gas and a quarter for a Qt. or two of oil. Man I was on my way!

Which 1954 engine are you rebuilding ? a 54 passanger car stick shif, or powerglide block or a 54 truck block, which lifter setup are you going to use? solids (truck) or hydraulic (powerglide).
Several differences in 235 heads are size of the water temp gauge hole, size of the combustion chamber (compression ratio) valve size, upper lube hookop that I know of, they could be some more differences, probably none that would not work on a 54 235 block. I am sure there will be someone that will straighten us out if I am wrong, they always do on this site.

[quote=Scott Andrews]I'm in the process of pulling together that parts needed to rebuild a 1954 235. I read numerous thread stating that the "848" head, beginning in 1956, is the best all-around head to use on the '54-'55 engines when rebuilding these as "drivers" as opposed to numbers-correct for judging purposes. My question is this: is there a cutoff year for this head when used with the '54 rocker setup? I know that the oil delivery setup to the rocker shafts changed beginning with the '59 engine, but I don't know enough about the later 235s to know if there's a cutoff year I need to observe when shopping for a bare cylinder head to avoid oiling problems to '54 the rocker shafts. Can anyone advise me on this?

Thank you very much, [/quote

This site is very knowledgeable for what your looking for.
http://www.langdonsstovebolt.com/ Good luck on your project!

Mr. Mack,

This is a 235 solid lifter engine. The engine, in this instance, came out of a 1/2-ton pickup. By the way, weren't all of the '54 235 115 HP engines used with the manual transmission equipped with solid lifters? I thought it was only the 125 HP engine for the PG-equipped passenger cars that had hydraulic lifters.

Thanks,

The main difference between the 1954-1955 head and the "848" for 1956 is the casting around the temperature sender. The rocker arm set-up is the same up through 1958. The 1954-1955 heads are the same with a 7.5 to 1 compression ratio. The first 848 head in 1956 had a 8.00 to 1 CR. Other than being cast differently around the temp. sender there is no difference from the 1954 head.
Being a 1954 truck 235 head iy may have the thinner 1953 style rocker arms.The 1954 cars got the stronger, taller rocker arms due to the higher lift cam and stronger valve springs used in the Power Glide engine. Also the PG engine was the only car/truck engine to have Hyd. lifters.

If you bought a new head for a 1953-1958 you got a 1962 head along with a bushing to adapt the temp. sender.\
The center rocker arm shaft oil connector was pinched off from 1959 and up because the oil fed to it was modified and the oil grove in the rocker arm was off set to one side to restrict the increased oil flow. This was done to help prevent the oiling to the rocker arms from plugging up - didn't do any good for those who didn't changed oil.

For general driving you will never notice the difference between the 7.5 to 1 and 8.00 to 1 CR.

Gene,

Thanks for all of that information -- you've given me lots to think about and look for. For instance, it never occurred to me that there might be a difference between the rocker towers and arms on the passenger car vs. truck engines. The difference in lift between truck and car engine hadn't occurred to me either -- time to break out my parts manual a see what's with this engine, and figure out what I need to shop for! The finished engine will going into a car, so I don't want this 235 to forced to lug too hard pulling hills with a set of passenger gears out back vs. the ratio used in the truck. Given what you say about the lack of difference in performance in a "driver" with 7.5 vs. 8:1 CR , I think I'll wait to see what the "doctor" says following inspection of the head and block for cracks -- if the existing casting is okay for rebuilding, then I'll stick with it and save a few bucks to reinvest in the rebuild.

By the way, do have any opinion about using exhaust valve rotators in addition to hardened seats and stellite exhaust valves? The engine rebuilder here likes using them when available, in addition to using guides with a spiral groove to promote better lubrication and prevent valve sticking on the any of the pre-1970's OHV engines he does. The absence of lead in the fuel was one problem, but he suspects that the increase he's seen lately in his customers being plagued by valve troubles such as sticking valves, along with galled stems and guides are linked to high ethanol content now being used in modern lead-free gasoline.

(In the similar vein, I've already had a misbehaving model B carb from my '52 216 deemed beyond repair according to a reputable guy I've dealt with for decades; he said the castings had become porous and brittle, possibly due to exposure to high levels of ethanol. His suspicions as to the cause are supported by a chemical engineer I work with, who says that tradition die castings with a high zinc content and ethanol don't "play well with one another," chemically speaking! More and more, it seems that this ethanol stuff is bad business for engines that don't have EFI and ECM systems to control fuel delivery and ignition!)

Thanks,

The 1954 truck may have the the weaker rocker arms - but they have the same lift as the sronger ones used from 1954 and up except possibly some early trucks. The "early" ones are the same as what was used on all 1950-1953 235 engines.
I could tell you what you have if I saw a picture of one intake and one exhaust. chevrolet beefed up the valve train area in 1954 due to the higher lift cam used in just the PG engines and an attempt to quiet the valve clatter on all engines with solid lifters. The truck is sort of an unknown area as some 1954 truck engines (early) had the small journal camshaft (and block)journals.


The heavy duty truck engine did have valve rotators. I myself wouldn't say they are necessary or a light duty driver. The 1954 light truck engine didn't have the best exaust valves. The Power Glide car engine used a good XCR ehaust valve. The exhaust valves are the same (size) for all 1948-1962 216,235, and 261 engines and all small block V-8 engines. I would get a good set of stainless steel exhaust valves. The is no reason to use rotators or to install hardened seats unless the seats have been ground down into the head due to having several valve jobs.
You can do what you want to the valve guides but if you allow the gas to get more than a year old (ethanol or not) it can cause a varnish on the valve stems and the intakes will stick.
I am sure your rebuilder will not agree with me but these engines will not have a valve seat recession problemdue to unleaded gas. I have used unleaded in my cars, driven many miles at high speeds and never had a problem.
Before WW II regular grade of gas had no lead....preimum was called ethyl and tetraethyl lead was addted to ethyl to raise the octane, had nothing to do with valves.

Gene,

That's good information about the exhaust valves and seats; until you stated this, I have always been concerned about erosion, especially in Nos. 5 & 6, where things tend to get a bit warmer when compared to the rest. I'll pull the valve cover and see if I can get a decent picture of the rocker arms, although I may end up having to clean them up a bit -- they're probably as black as coal!

Thanks,

Have agree with you on the subject ( as always ) Rebuilders will try and talk you into hardened seats because of the lack of lead in unleaded gas...What a crock...Or parts stores will try to sell you an additive to add lead to your gas as a lube to keep the valve seats from damage...Think "snake oil"...lol Keep the money in your wallet...Better yet, send it to Gene...

I also agree as well.