Thanks for the pictures '37, and the explanation T-Head. My '24 DB had two piece valves when I got it, head was cast iron swedged onto a steel stem. Was this common back then?
Any idea why they milled away the center edges? Brings back memories of doing the same shell work on the Coverdale MERCER back in the 1980's.
Didn't fastener quality improve too? I can't get over your replacements, 4140 is moderate strength about grade 5 and the cut threads make them closer to grade 2. 1906 Joe Tracy and Al Poole 90 hp Locomobile
1930s, THE AUTO magazine, UK. Does anyone know a history of this UK publication and is it still in existence? Many thanks.
Keith, I'm reading his book right now Outlaw Sprint Car Racer- ckocked full of early sprint racing info in the midwest. It'x a good read
Mac, Do you have the ISBN number for that book ? if so i would see if i can get my hands on it . . Keith
Sure, It's 0-9627653-9-2 Lots of day-to-day info as well as a fairly detailed look at the sprinter you posted above. It's amazing what these guys did with parts back then!... and giving me LOTS of bad ideas for my speedster !
Speaking of having bad ideas... I posted a while back about trying to find more pics (profile, etc) of the Sig Haugdahl/Mabel Cody Frontenac to get a better idea of the flow of the tail (might try to imitate it when building the speedster)- after doing a little research, their Fronty has the same body shell as the Indy Fronty's. Does anyone have a good profile of Chevrolet's Indy car (the Monroe Spl might even share the same body type)? Thanks as always, Bill
Seeing the photo of the Fronty rocker arm head in Mac's post above reminded me of something I am looking for. I need a set of period, down, side or up draft carburetors and a manifold for my model T Rajo BB head. Does anybody know of any? The ports are 1 5/8" and the bolt holes are 3" center to center. I also need a ZR4 Bosch two spark mag and a cap for one also, see photos 2-5. The cap has two sets of plug wires and if you look inside you can see the double rotor. This type of mag fires two plugs per cyl. and I need one for this head. It has another set of plugs on the other side. I am also looking for any T racing equipment or cars.
Some of you guys have some great stuff in your garages. I'm jealous. I think i'll put the word out on what i need for mine. If someone has a Montier head or two for a Ford Model A/B or any leads to said items, please let me know. To be truthful and realistic, these things aren't exactly falling out of trees so i don't expect a reply but the odd one has been found in Sth. America out of all places.
there are a couple of mag's for sale on the HCCA site... Bosch D6 Magneto Bosch D6 Magneto, Model 2-Spark, Dual (rare). $4,500.00. Bakersfield Swap Meet delivery available. Contact: James Zordich, Boring, Oregon, 503-663-0115
In our last post I showed you why we are going to make new insert bearings. Before we can do that we have to machine a new bronze cap to replace the center cap (photo 1 & 2) that was milled off flat and reinforced with a steel plate. This cap is was modified by an early restorer in the late 40's because he knew it was going to break at some point one way or the other. I am going to replace this with a newly cast bronze cap (photo 3 & 4) which as I mentioned earlier is what they did on all of the factory racing cars. The manganese bronze this is cast out of is extremely strong. The bottom is faced flat in the milling machine along with the bolt holes being machined to the same center to center distance as the crankcase bolt holes. The bronze tube sitting on the milling machine table will be machined later into our new inserts. Next the caps are all torqued down tight with our new bolts and the crankcase is set up in the align boring machine (photo 5 & 6). This is a very large Tobin-Arp machine which is very versatile and can handle blocks up to over 60" long. The crank case sits on top of and is attached to the adjustable parallels you can see below it. The two arms you see holding the boring bar are placed on either side of the case next. A dial indicator is inserted into the bearing on each arm and used to measure the bore in the crankcase so that it can be precisely centered to the arms. The adjustable parallels allow you move either side up or down along with in and out to locate to front and rear bores at a true dead center with the arms which hold the boring bar. After this is accomplished you are assured that your new bore will be where the manufacturer originally put it. This is where most people stop and proceed to bore. I always take the time to figure out and measure two other important things rather than to trust the original case. One is to calculate the ideal center to center distance of the timing gears. This distance is then checked and if it is off I can adjust to correct it. Then having this set you need to check that both the front and rear distances from the boring bar to the top of the crankcase are exactly the same so that the crankshaft ends up being perfectly parallel to the top of the crankcase. This is basically what they call blueprinting today, making sure that all of the dimensions are correct. It is time consuming but by doing it the pistons and rods with be at exact right angles to the crank and cylinders so everything will run smoother with less friction and it will produce more power and last longer. It is then time to bore out each main bearing bore and cap until the hole cleans up round and true. After we are done we also have all the holes is perfect alignment front to back which is very important. Next time we will machine the new bearing inserts. On this machine the two arms are moved to each bearing and it is bored and then they are moved to the next bearing. There are high precision ways that locate these arms (one is the vee at the front top the other is on the back side). You can bore a 9 main bearing straight eight on this machine with only .0015" clearance (one and a half thousandths) which is half the thickness of the average human hair and the crankshaft will turn perfectly without any binding in the bearings.
And some of those guys did miraculous things with those T-based racers. Think Winfield and Lockhart to name a few.
Add to the above, Noel Bullock who with this Model T that he built for dirt track racing and which looked like a rolling junk pile (on purpose). He decided to go to Pikes Peak to enter the hill climb. When he arrived all the big guy's laughed at him and told him to go back home. He was able to eventually enter by being friendly with the old guard and he ended up winning the thing and made them all eat crow. The next year they set a minimum weight so they would not be embarrassed again by a Ford. His car was all Ford parts except the Rajo head, carbs, igniton, accessory transmission and the wire wheels. He has been my hero since I was a kid.
T Head, now that the two halves are oval since they lost the thickness of the cutter do you add a shim to made them round?
Sorry I left a little info out, I edited it to put it in the text. This system gives you a slighly oval bearing after cutting but when clamped in a round bore it becomes perfectly round. I did make some thick bronze shims for this job as they take the place of the original shim pack. They keep the hole as round as possible before boring but do not go between the two halfs of the bearing insert. Look at this photo again and you can see how these shims are only between the cap and case. Also look post 2790 below for photos of how this type of bearing sits in the bore.
I'm sorry I didn't get a message and only sent one. The 'crime against nature' Carroll Smith quote was from the top of my head, he mentions it in a couple of his books. I've attached the page from Engineer to Win where he revisits it. I watched an interesting thing on tv last night about a 747 that lost 2 engines almost simultaneously. One of the four fuse pins that hold each engine to the wing in shear failed resulting in the opposite lug breaking and two rear fuse pins shearing and that engine knocking the other off. The fuse pin which is designed to shear from the vibration of an out of balance engine that's suffered a bird strike or such so it doesn't destroy the wing failed prematurely from a fatigue crack emminating from a microscopic machining mark.
All the fun of the Rockville fair 1923. Maryland I guess, some of the most adventurous photography I've seen from the era.
The Jalopy Journal
