Thanks JimmyB, I know that it was mentioned on this thread that feeding oil to the bottom of the bearing is not a good idea, but when that's about the only option, it doesn't give much room for an alternative. The '25 block is desireable because the center main web isn't cut away for the distributer and studs for the cap an be run all the way through to the space between cylinders 2 and 3. When I built our girdle for the five main crank in the 557 roadster, it has studs mounted in the girdle for the front and center mains. The studs make it kind of impossible to feed oil to the top of the bearing. So, like most of the things done on that engine, a good dose of, "Country Boy" engineering was applied. In my mind, the crank is supported, hopefully, on a somewhat uniform film of oil, so supplying oil to the film at the bottom should not be that much different than supplying it to the film at the top. We didn't have any bearing failures doing it that way so I guess it works. It would be kind of like holding a grease pencil to the bottom of a rotating shaft. It would put grease on the shaft without having to support the shaft on the end of the pencil.
jimmy b The engine picture you posted (#410) had a piston with a dome in one hole and the other piston seemed to be flat, ---could be the lighting?? question is, what pistons are they?
Default Re: 1928 chevy 4cyl motor jimmy b The engine picture you posted (#410) had a piston with a dome in one hole and the other piston seemed to be flat, ---could be the lighting?? question is, what pistons are they? I noticed that also I think they are different.
It does look like a dome piston I don't know anything about it the pics are from an Auction 2-3 years ago. The car is back on ebay it is a '23 track T.
V4: Send the pictures to the VCCA chat forum. They'll can give you the best answers. And if you can get any cast numbers from the block and head, send them as well.
Jimmy B After looking at it ten or more times, I noticed that the green three port motor you pictured has a much different head than mine or the others I've seen. (the intake ports are pointed up). Whats the deal with that? what is this head off of?
That is a Roof head, ultra rare. http://www.museumofamericanspeed.com/Collections/Engines/E123.shtml More from Speedy Bill's collection http://www.museumofamericanspeed.com/Collections/Engines/E122.shtml http://www.museumofamericanspeed.com/Collections/Engines/E117.shtml
Model T Haven has a 1928 Chevrolet chassis for sale, with engine, in their parts section. $850. Speaking of chassis. What is everyone putting these ‘28 Chevy bangers into? I kind of envision one swapped into a fenderless, gow-job Ford roadster - but maybe some of you are building street-going streamliners ala Rufi? Or maybe even actual 1928 Chevrolets? -Dave
Avatar frame is made from 7ga. steel formed to channel section. Had both a 28 Chev. and Ford A frame at the time, but made my own. Did use the A rear crossmember though. Herb Kephart
Herb, Is that the 27 Chevy speedster thats referenced in your profile? That is a tiny pic. Did you build it as a 3-springer? Home-built speedster body? -Dave
Dave -It is the car. Here is a description that I wrote for an ad a while back, and some larger pictures. <meta http-equiv="CONTENT-TYPE" content="text/html; charset=utf-8"><title></title><meta name="GENERATOR" content="OpenOffice.org 3.2 (Win32)"><style type="text/css"> <!-- @page { margin: 0.79in } P { margin-bottom: 0.08in } A:link { so-language: zxx } --> </style> This car is hand built, and is one of a kind. It is powered by a '27 Chevy 4, with a counterweighted /drilled for oil pressure/ balanced crankshaft. Rods and mains insert bearing The head is the sought after Olds three port, with large valves and 1 ½ to1 aluminum rockers. Cam is re profiled for more duration. Cam gear modified so cam can be retarded/advanced relative to crankshaft. Rods are Ford A, pistons special- about 6.5-1 compression. Intake manifold modified to take larger (but still updraft) carburetor . Lightened and balanced clutch and flywheel, driving Volvo 4 speed transmission. Open drive line to Ford 3.78 rear with straddle mount pinion. I built the car about 20 years ago, and my aim was to build a car that, on first glance, looked like it could have been built in the late 20's-early 30's. The one glaring exception to this is the transmission- but since one has to crawl under the car to see it, I elected to have easy shifting, and quiet gears. The frame rails are formed from the same gage steel Ford used, with an A rear crossmember and springs. Front axle is Ford,.”bulldog” spring mount with 14” (YES, FOURTEEN INCH!) mechanical brakes- again to keep the period look, with good stopping ability. Wheels are 19” Ford. Body is aluminum, over an ash framework, fenders '27 T fiberglass repro. Dash has full instrumentation, including chronometric tachometer. Nice trunk, and bucket seats. No top. Total mileage since build, about 3K . Never got used much, as I prefer closed cars, and have a '30 Tudor, with Schofield OHV B engine. Also have '28 Chevy coupe that is in progress, which means 3 cars to fit into 2 bay garage- hence proposed sale. Herb
Dave, I'll be using a '28 chassis (might make the framerails parallel) and building a body either like a Mercury speedster or something close to the Fronty 300 body.
So a guy with whom I used to work invited me to his house for a CarBque today. He lives down the street from Orical. Nice neighborhod. His neighbors and he had closed off 4 blocks, cleared all local normal parked cars form the street and driveways. And parked Hot Rods, restored cars race cars and what have you on the street, in peoples driveways all over the place. And they barbequed food and had drinks and all for free. Unreal. But anyway one car there was a restored 26 Chevy touring. I got talking to the owner and he educated me that the motor I bought is a '28 as It has an oil pump in the pan driven off the end of the distributer which drives off the middle of the cam. Much the same as a 235. So I learned something besides there are a lot of people who live near John that are pretty cool.
So Rich, did you meet up with the guy that knew about your engine, or did I just miss your post about it? Also, on a non Chevy kind of thought, take a look at the newest Hemmings Classic mag, pretty cool blue '27 roadster in it.
While looking through my notes for something else, I came across the following info. These are the clearances between rods and crankcase (or cam) at the closest positions, and the approximate crank position that they occur for stock rods and crankshaft in a C4 Head of rod bolt/core of cam--3/8"--20* BTDC Side of rod beam/cylinder notch--5/16"--80* BTDC Nut seat surface of rod/cam side crankcase wall--3/16"--90* BTDC Side of big end of rod/ crankcase wall opposite cam--5/16"--90*ATDC A Ford rods will fit without any rework--B Ford WILL NOT. Herb Kephart---now I have to remember what I started out looking for---------
Been wondering about that picture that Jimmy posted a few pages back that had the "mysterious piston": And then I saw these for sale on Espay- described as cast iron T jugs: <?xml:namespace prefix = v ns = "urn:schemas-microsoft-com:vml" /><v:shapetype id=_x0000_t75 stroked="f" filled="f" path="m@4@5l@4@11@9@11@9@5xe" oreferrelative="t" o:spt="75" coordsize="21600,21600"> </v:shapetype> <v:shapetype stroked="f" filled="f" path="m@4@5l@4@11@9@11@9@5xe" oreferrelative="t" o:spt="75" coordsize="21600,21600"></v:shapetype>
I'm going to try posting my first pictures. Wish me luck. I purchased a three port head a short time ago. It turns out it's not exactly a virgin. It was off a racer at some point. The valves are way big and longer than stock. Stems are oversize too. Big springs and a long notch for the keeper. A set of 50/50 rockers were included, but I don't know if they were ever used with this head. The push rod hole in the head was butchered with a grinder. It may have been done to make clearance for the rocker adjustment nuts. In their stock location the 50/50 rocker assemblies would have to operate at a rather severe angle. I took an extra top cap and placed it under the shaft. This made the rocker angle ok but longer pushrods will be needed. Someone earlier in this thread suggested milling the stands down to the head surface. My thought is to just a light cut to true the surface. Make new stands out of 1.20 in. thick aluminum and use the head bolt and one rocker stand bolt to mount it to the head. The rocker shaft could then be located for the '28 rockers (or others) and the longer stem valves and a more standard spring could be used. The stands could be drilled for pressure oiling, etc. etc. The pictures I'm going to attempt attach show most of what I'm trying to do. Any imput to improve on this idea are welcome.
I'm the one that you refer to, about milling th rocker stands off. You are correct about the rocker angle in your photos- at the midway point in the valve lift, the rocker should be at right angles to the valve stem. Using one of the rocker stand bolts and a head bolt to hold the new stand down is OK, and is what I have done, but I wouldn't use aluminum under a head bolt. Also, if you do it the way you described BE AWARE that the head bolts are 1/2-12 (12 threads per inch), whereas any coarse thread 1/2" bolts since the first world war are 1/2-13. Not likely that you will find 1/2-12 bolts that are longer--they will have to be made. More brilliant GM engineering! I would not put oil pressure to the rockers, you will never be able to seal up the top end enough to keep the oil in, and what leaks from the rockers will be lost--just to make a mess. I could say more brilliant engineering, but the oiling by felt pad over the rockers was common in that era, and believe it or not, works quite satisfactorily. One other comment- I have seen MANY '28 rockers that were severely bent just by over-reving a stock engine. Stock valve spring pressure is 40# seated, as I recall. With stiffer springs '28 rockers don't stand a chance--hence the search by Mac the Yankee, and others for better 1 1/2 to 1 rockers. Herb Kephart
Norsonauto, I suggested milling the stands down so that a Chevy 216 standoff could be installed. I am going to cut the bottom of the 216 standoff and use it to adapt to a shortened 216 rocker shaft. By milling the stands down to flat it will allow me to drill and tap a hole to bolt the extreemly shortened 216 standoff to the head. The advantages are great in using the 216 Chevy 6 rocker arm setup. The 216 rocker arm shaft is hollow allowing pressure oiling. This set up also has the advantage of the 1.5 to 1 rocker arms. The 216 comes with 6 more or less straight rocker arms, 3 right offset arms and 3 left offset arms. This means that it takes 2 216 rocker arm assemblies to get enough straight arms to provide the 8 that are needed. The springs, washers and oiler tubes can be judiciously adapted to work on either the Olds or the Chevy heads. Today I noticed that the existing holes in the 216 shaft don't line up with the Chevy rocker stands but 2 of the three are close enough that by milling them each a little closer together they will work. The 216 standoffs will cover the out of round holes and everything else is just a matter of aligning the rocker arms with the valve stems. The picture below shows the 216 standoff with tape at about the cut off point. This can be determined after the original stands have been milled flat and pushrods have been selected. In the second picture I show the shaft with the standoff in position and the oiler in the position that it would go in the 216 Chevy 6. It would have the other half of the complete 216 rocker arm assembly on the other side of the oiler tube. I will remove the pins from the oiler assemblies and install them in the middle of each rocker arm shaft using a set screw thru a hold drilled in the appropriate location on the shaft. . Dick .
Rich- Did you ever get together with the fellow who built your engine? Herb- I was wondering if the shaft oiler from the 6 would be a help or a hinderance... any chance of making it work?
No problem with getting oil to the rockers-- Just one h##l of a job to keep it from leaking out of the rockerbox by draining down the pushrod holes, and the irregular head to rocker box surface. And don't think for one minute that those tin covers over the pushrods on a '28 are going to do anything more than keep the local aardvarks out. They were specifically designed to allow dirt in and let oil out, I think. Rich- I made studs 1/2-12 bottom, 1/2-20 top
Thanks Herb. I had already noticed the thread issue, but was sure how to address it. I think your approach of making new studs is the way I'll do it. What stock did you use? Thanks for the input on the material for the stands.
I bought grade 8 1/2-20 bolts long enough to remove the heads and cut 1/2-12 threads with a lathe. Probably the best pieces of material in the whole engine ;-) Herb Kephart
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