Don't your dare stop! Really, I like to see how someone goes about this kind of stuff. (And get envious of your shop!) I'm signed up for the duration! Thanks Stueeee!
Yup, I don't think you can go into too-much detail here. Go ahead n try! . This kind of thread is needed badly here. Thanks for posting pics n info. Marcus... BTW, do you kinda guess at the metal thickness in places where you can't determine, or use a sonic checker, or? Thinking ports, bowls, seat areas, etc.
Looking at that flat head surface am wondering if we have we covered the Heron Head concept for chev 4 on this thread yet. I seem to recall Herb talking about dished pistons at some stage but cant find it again.
Heron head? Kume- we've talked about how the early racers would simply screw a cap to the top of their pistons to get higher compression, but don't think dished pistons and/or a Heron head were brought up- DO tell
Absolutely not!! keep it coming, I have a 3 port Olds head that I'm needing to do all of the same to and more, I need to fix to top of the head first. My best plan, so far is to mill it flat and make a top cover pate that can be the mount for better rockers, the only concern there is finding good (thick enough) metal to bolt into!!
All, thanks for the kind words, I'll put up more photos and text as I press on. @Blackbob, I saw that Olds head down at Andy McCann's when I picked up a '28 motor from him. Bizarre how it ever got to be in that state. Have you considered Hooking some 1/8" or 3mm steel plate under the holes and brazing them into place using a Manganese Bronze rod? I have repaired two cylinder heads using this method -admittedly cracks/holes without such extensive damage- but both these repairs have held up OK in use. Doing this style of repair would leave you the option of shaving those Olds rocker mounts down a bit, but still leaving them with enough material to bolt some new rocker posts onto. To do the Brazing, I did an initial preheat of the head with the domestic oven on max for a couple of hours (wife/girlfriend/partner definitely needs to be out at this time) Then had a mate with a big propane torch heating the underside while I used an Oxy Acetylene torch with a number 18 nozzle to heat the area where I brazed up the repair.
Blackbob/Stueeee Do the holes look man made? (not freeze breaks) I saw a Roof Head for a Chevy years ago that looked like that. The holes looked like they were gouged out with an arc welder. (turned way up with wet rod) But why?????
Great work with the special made cutting tools piloting off of the valve stem bores. Nice to see almost hundred year old machinery coming back to life.
That is similar to what I had hoped to get done by a good friend who is a very good welder (sadly I am not) but he is a bit wary of doing the job as he fears that he will damage the head beyond repair. That is why I have been thinking along these lines, as done in these pics by a fella on the MTFCA for a fast T. He used 1:1.375 ratio rockers, SBC valves and a 260 cam
They look like they have been broken out deliberately, maybe done back in the day to see how much material there was for reference for work to be done on a better head, maybe this one already had frost damage, who knows. It's got to be worth trying to get it serviceable again. I'm still not sure if I'll use it on my '28 Chevy motor (ive got a good Chevy head for it) or a T block with a SCAT crank, time will tell!
well, it seems there's some appetite on here for more of my cylinder head ramblings. First of all I pulled out the pressed in tubes that the factory installed to retain the stock daisy diffuser things. Although removing these does mean that the siamesed inlet ports are now a rather odd shape, putting them back would divert the mixture away from the area of maximum flow for each valve throat; so they'll be staying out. Here's the head set up ready to blend the previously pilot cut valve throats and do some work on the ports. I've re-drilled this Cheapanese engine stand so that the original 8 rotary positions are now 48 rotary positions, which usually allows me to get the head at a good attitude to easily see whatever area I'm working on. As usual I've got my shop vacuum cleaner sucking on whatever port I'm working on. The steel ring that's clamped on the head face is there to make sure I can't accidently run a grindstone into the valve seat area. These are the tools use most of the time to do porting, the flexible drive runs at 11,000 revs, although it has an on/off switch on top of it, I use it wired via a foot pedal which gives better control and safety. The Makita die grinder runs at something like 30,000 revs, so works especially well with small mounted points. Talking of mounted points, here are some of them, you can see that for port work I have extended some of the ones near the front of the block, this makes working deep into the port with a die grinder or flexy drive much easier. The mounted points are Loctited into the the home made adapters. When the point wears out, heating the adapter with a blowtorch melts the Loctite, and a new grinding point can be Loctited in once the adapter cools down. I've got the inlet valve throats done for shape now. I'll do the ports and short side radius next.
Playin a bit of catch up here... I found the 10mm plugs to be fairly common in the motorcycle world, an available in a wide variety of reach lengths and core materials. I had a similar shrouded plug issue in my Akron-Hed project, and made up adapters to install copper core 10mm x 27mm reach plugs. You can see in the cross section that I had to lower the sealing surface of the plug down into the 1/2” pipe thread to get the electrode into the combustion chamber. I have not run em yet, and not sure how their gonna work... but I’m dedicated to the size and not goin back without trying every plug in the book!!
Kevin Thank you for your belated reply! It is still really good stuff, and I will be looking into 10mm plugs. Please ad any updates on your endeavor!
Here is the plug number that I’m going to try first. Heat range 7, 8, and 9 seem to be all that is available, and all kinds of electrode material options too. These are copper core, heat range 7...
My opinion, for what it's worth. is that the plug points should be as far into the chamber as possible. You have a combustion chamber that has no turbulence to get the mixture to sweep past the plug, so I always found that (either) Chev head needed a lot of spark advance. I ran 35-38 degrees BTDC at idle. Don't have any threads exposed in the combustion chamber, grind those areas around the plug hole smooth--I burnt a hole through the top of an aluminum piston by not doing this, and with all the wind noise in an open car at speed, I didn't hear the pre-ignition noise. As to moving the rockers, here is a photo of the head that I had on my avatar car. The rockers are one and a half to one. As I recall, I didn't mill the top of the head flat all over, and as I recall I reused one of the old bolt holes that held the old rocker stands. Unfortunately, I dont have a photo of the head with just the stands on it. Here is the best that I have to show the stands. I always forget to take in process shots until too late. Can't seem to get the photo down where it agrees with the text. Electronics and old farts aren't compatible. Herb
This is the lifter in the block. You can see that it will run into the cam bearing, l am spinning them in the lathe and grinding off the outside to get them away. I'm only doing the ones next to the cam, what do you think!
These lifters are adjustable, l don't need that, l wonder what they came out of. I was thinking a DB but they are all flathead. What did the Oldsmobile lifters look like?
In the past, I've picked up similar looking ones, but the adjusting bolt had a flat head. I was thinking that they were out of a flat head six Dodge. Unfortunately I did not add a marked card or ID to tell where they came from!?!? It's good to see you working on yours! Be careful and have fun!
5/8 body lifters are pretty common. When I converted my 32 Plymouth to OHV I used new International Harvester Red Diamond lifters. They were for an OHV engine and nonadjustable.
Question, Does anyone know if you can use you can use the timing gears gears from the 6 cylinder? What I need is the crank gear, Somehow I've lost the ones to this. I have the oil pump that goes on this cover; the the little makeshift cover on the right I haven't been able to figure out what that could have been for!
Glad to see this thread is still alive, took me a few days to read through it all. I have a 28 engine I am building for a speedster. My build will probably be mild, at least the first time around. Thanks to all of you for sharing. Dan
I'm glad to see that this thread is still alive, but I fear that the fellow's that know anything about the Speed Chasers is alive!
This is my uncle Ed, my dad and he used to run cars on the lake beds in the 40's Ed was born in 27, my dad in 29. There's a lot of questions I would like to ask! It was fun growing up around the cars. My grandson has a little interest and wants to help finish the car. LOL, I keep telling him nothing newer than 1940.
The Jalopy Journal
