Those carbs look great, Kume. I've got a later pair off a Big Healey I've been thinking about using. What are those off of originally?
Am not sure what they are off. They were fitted to numerous British cars from the 1920s on. These are 1 & 1/8 brass bodies and float bowls from the 1920s. I suspect it is going to be trial and error with carbs on this build.
Off a mid to late 20's car of some sort I think with those Bronze float chambers. Early 30s SU carbs had a bronze body but had alloy float chambers. SU seemed to be a bit late t the party on die casting; some of the 2" and up carbs from the late 30s were still sand cast.
Kume I've been trying to match up a t5 transmition to the c4. I did like you and had the skirt machined off, have not counterbored for the flywheel to crank bolts, the springs on the newer disc interfere, replaced nuts with some jamb nuts for now. My speedster has the little newer 9" chevy springed disc and does not interfere. So things are close, will counter bore and replace bolts with #8's. Next time you have your clutch out, I sure would like to see a picture of it!!!!
Pics & some more info on my build. The chap doing the engineering work for me has successfully raced a 1923 chev for many years so am following what he has done and am drawing on his experience. 1926 block Flywheel skirt machined off, holes drilled & for Holden HQ clutch pressure plate, taper head bolts with cone friction washers 60lb torque & threaded crank shaft mounting holes. Strengthened centre main cap. Mushroom cam followers - still trying to find out original application for these. 1928 cam grind. High compression pistons. Chev 6 cyl oil pump. Some grinding required to fit beside new centre main cap & new drive peg for distributor. May fit 1925 front engine plate to run a magneto as an option. 3 port Oldsmobile head with twin SU's as per earlier posting. Tappet fulcrum still to be moved. Everything balanced. The motor is going into a 1926 Model T Roadster for which I started a build thread for a million years ago. Using 1928 chev gearbox. Have fitted 1927 chev rear end with 1928 chev brake drums and modified hubs to take 1928 Ford Model A 21 inch wheels.
Great work there. Do you know which Chevy six oil pump you're using? The 216, splash and pressure lubed 235 variants seem to have three different oil pumps.
I Not sure Stueee - I will find out. Would be interesting to know if pumps from early Vauxhall or Bedford 6 could be used. Were they not an improved version of the Chev 6 ?.
A couple of Chev 4 specials for sale https://www.prewarcar.com/294513-chevy-national-boardtrack-racecar https://www.carandclassic.co.uk/car/C940636
Kume--I would recommend that you put at least 2 dowel pins opposite each other, and between the flywheel/crank screws. Don't bother asking how I know. One between each pair of screws is better, but don't go over ¼" diameter on any. Stueee- I used 235 Chevy oil pumps from the mid '50's Notice that I made a new bottom plate I'm still alive (more or less) and once in a while I am able to get on here--but most times the whole site doesn't want to have anything to do with me. Sob Sob Herb
Grumpy Since it is obvious that milling the head isn't going to get you any more compression, taking a cut off the top of the block was sometimes resorted to. Stock deck iron in the block. Work on the longer tubular rods for for the larger 224cu inch 4 discontinued, it looked that they were going to end up too heavy. Other sinister plans may hatch.
Herb, thanks for the information regarding the oil pump, I'll put a 235 pump on my ever lengthening shopping list.
Herb, It's good to hear from you. We are ready to hear all your secrets. Well, the ones about Chevy Fours at least.
I’m selling a 1928 short motor in good nick and 1921 Olds 3-port head (needs repair). I’ll post up in the classifieds soon but get in touch if anyone is interested. Based in UK I was keeping them as spare but I’ve got plenty to keep me going
Merry Christmas and Happy New Year Everyone!! Keep warm and snug, and for you that are down under, keep cool and in the shade!!
Merry Christmas all! While pulling parts from the pile and moving my '26 roadster build to a friend's shop to actually get it done I have discovered that one of the hangups was that there are at least two cars hiding in the pile. One is the 153 Chevy II powered '26. The other is a much leaner '28 chevy/Olds head powered '24 Chevy cowled racer. It is getting sorted into another pile. Does anyone else remember hearing about a new made Ford model "C" crank? I'm sure someone was making them a few years ago. Or Possibly a new "B" crank.
I'm going to try putting up a picture we'll see how this goes! I think it worked! I finally made it down to San Mateo to Rich Fox's and brought back the midget 28 . The first pic. is partially unloaded, second is where it's going to call home until I can open up better digs for it. I did not notice the surface rust on the rockers until I looked at my own post! (pic is highlighted) Was a very wet trip! Need to get to shop today and 'NIX'
Grumpy, is that a second bellhousing I see on top of that blue box? If you'd be interested in parting with it I could use one for this engine I picked up recently.
Merry Christmas everyone I re-read the thread in the past few days and came with a few ideas, well, they are actually more like questions, but anyways... - As Egor showed in post 1731, there is enough space for mushroom lifters. So, can the lifter bores in the block be bushed? if yes, an option would be Ford Y block lifters, they have a diameter of .498-.499" and a seat height of around 2.6" (depending on the manufacturer). - I haven't seen much talk about rings, would a "modern" ring set be beneficial for the Chevy 4 (assuming a custom piston is used), or the materials on the block make such change pointless - On the subject of lubrication, it seems like there are plenty of options for oil pumps, so there is no point in searching new ones. I just noticed that the Willys 134/161 oil pumps can be easily used as an external one. the gear can be easily changed to a pulley, and a simple machined "adapter" could be used to mount the oil lines, align the pulley, and lubricate the pump shaft. a plus would be using the pump found in Brazilian market Mavericks equipped with the Willys 184 engine, which incorporates a full flow oil filter, - Lastly, through the thread, it was said (and showed) that to mount custom rockers on Olds heads, it is necessary to mill the top of the head flat, but the rockers that Six Ball showed on post 2065, seem to be mounted on a plate above the original shaft location. Is there any advantage in doing so? (also, i believe the rockers would have to be designed differently to correct the geometry).
I also realized 2 things reading the thread, both influence the piston/rod combinations: - The specs for the 1928 engine has the deck height as 12 23/64" (12.359375"), and not 12.5" as has been said on the thread. I'm not claiming this is the actual height, as i have not measured any of my engines, but i believe GM wouldn't print a spec off by 0.14" - it seems nobody accounted for the fact that the bores of the chevy engine are 3/8" offset from the crank, meaning that at "crank TDC" (when the crank is at the top of the stroke) the rod is a little angled (as illustrated below). Since it's only 3/8" it has little effect, but i accounted for it anyway It should be noted that "crank TDC" is not actual TDC, so any combination should be tested with the actual parts, as previously stated on the thread. I decided to redo the chart posted some time ago. I used SketchUp for measuring, so it isn't as accurate as it would be if i used CAD or something, but i believe it serves as a rough basis. (measurements above are all in inches. Durant+270V is above deck)
GraeffSS, Thanks for checking the numbers and finding some possible errors. I used numbers quoted here somewhere so if they aren't right we need to know. The Olds head I have has not been modified and the guy I got it from made those rockers. I'll talk to him and see if the stands have to be removed to use them. I think they do. In a thread like this some incorrect info sometimes gets posted and then lives on. I did not know about the cylinder to crank off set. It would be nice to have a post that gives all of the specs in one spot. Thanks for your help.
No problem, with engines like these precise numbers are hard to find, so an error here and there shouldn't be uncommon (it seems not even gm knows what the exact deck height is, as I've found another source claiming 12 3/8") About the head, it would be nice to know, even if there is no advantage in keeping the stock stands Sent from my ASUS_X00DDA using The H.A.M.B. mobile app
Six Ball ask Mel about the lifters in his race car also. He was going to use y-block lifters in that first block, how did they work out? Graeff yes the lifter bores can be bushed. Remember that the 28 engine have larger lifters than the earlier engines, also the pushrod goes to almost the bottom of the (hollow) lifter. GM may have had wear problems on the earlier lifter bores?????
Ok, I'll have to make some notes. I wish I could get him on here but his computer got messed up a few years ago online and the stays away now.
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