1930s Era Champ Car - new project

Thanks Mike. It did not solve my mystery but I can now say "I am confused on a much higher level".

 

Might not work, however have you considered one of those cut to fit axles like Currie and others sell?

 

Yes I did. But they do not list one for a truck 5 x 5.5 bolt pattern. Plus there still is the question of matching up brake assemblies and drums.

I ordered a custom axle shaft built to the specs I supplied them along with 11 x 1.75 brake assemblies from Quick Performance in Ames IA. It should be here in a couple of weeks.

I still would like to know what this axle came from.

 

No tag on the axle?

 

OUCH $$$!

 

nope - none. I acquired it from a friends stash and he only had a vague remembrance that it was from an '81 Bronco, which it isn't.

OUCH $$$$$ but I'm done pinching pennies on this project. If it is to get finished in a timely manner I need to step to the plate.
As my son likes to say," The first 90% of the project takes 90% of the budget and the last 10% of the project takes the other 90%."

 

I'm in full agreement with that! You don't want to see this week's discover bill alone. Fortunately SWMBO tolerates my occasional excesses! Besides we can't take it with us!

 

LOL SWMBO - I had to look that up.
I get that.

 

After a week of vacationing on another planet I arrived home to see that my new axle arrived. The new brake assemblies were not with the axle. I unboxed it in anticipation and it looked real pretty. I planned to remove the rear axle housing from the car, clean and paint it, and install the 3.25 posi center section so I can take some measurements and make a driveshaft.


Then the Fit hit the Shan.

Comparing it to my old axle the bearing was 1/2" inboard of the old axle. That certainly will not do as the drum and wheel will not be in their proper position. I will call the supplier tomorrow to get this resolved but at the very least it means more delays to the project.

 

After some further searching on the HAMB I was able to locate the backing plate part numbers for the 11 x 1.75 Bendix backing plates:
305503-L left
and
305504 - R right
Does that help anybody ID this rather elusive truck axle?

 

Bummer! Hope it works out for you. That's quite a bit of offset difference.

 

After a chat with the supplier I carefully measured my axle so he can make me a correct part.

 

After a phone conversation with the axle supplier I will be getting another axle built to fit my housing.

Today a set of brakes was delivered from the same supplier. I got a tight knot in my stomach as I figured they were not going to fit. After unpacking them I measured the shoes - 2.25" wide. My old shoes are 1.75" wide. So I thought I was now going to have to send the brakes back. I noticed the drums had been drilled for my 5 x 5.5 bolt pattern (there was still evidence of burrs on the holes from modifying them). So at this point I figured I'd try the wider brakes and different backing plates with my one good old axle and guess what!!! It looks like the whole she-bang is going to work. That is actually an upgrade with the wider shoes, self-adjusting ratchets and equalizer bars.



What is the best method to paint the brake drums? I'm thinking clean and prime and paint with hi-temp engine enamel, no?

 

While I am waiting to get a replacement axle I will make the driveshaft. I installed a 3.25:1 Equa-Lock (posi) third member to measure the C-C U-joint lengths. It will need to be 12.25", allowing 7/8" of input shaft stickout. I had a used driveshaft that I cut up. I will shorten it. I do not plan to have it balanced due to its short length, but I will remove the weld seam flash from inside of the tube to insure the tube is as concentric as possible. Also, there is a balance weight that I will leave on. The C6 yoke needs to be swapped out for the smaller C4 yoke too. And all new U-joints of course.

 

Crazy story! We needed a driveshaft back in the DIRT track days. Relatively short, approximately 27-28 inches between u-joints. And it was a Friday night and no way to get to a machine shop before Saturday night. What to do? Hmmmm...

Take 2 transmission yolks that had the same u-joints as the one in the transmission and the quick change, find a section of tubing that just by chance had the right id to just slip over the splined parts, cut to length, and weld it all together in phase.

It worked out rather well, and stayed in the car for a couple of weeks until a proper driveshaft was made. It was wrapped up in an old towel and visqueen, and went with us as a spare. Never had to use it again, but at least we had a spare!

A side benefit, more room around the shaft.

 

That's a good story Dave and a good example of the "desperate people do desperate things" principal.
I was once at an out-of-state race and the ladder bar bushings got hammered out, making the car ('33 Willys) evil handling. I went around to all the trash barrels finding aluminum pop cans that I was going to cut up into shim strips to roll into the ladder bar ends. But other issues forced me to park the car for the weekend.

 

Here is a sidebar tech tip on how I shorten driveshafts. But before I go on I will give my South Park style of liability disclaimer:

CAUTION: ROTATING AUTOMOTIVE PARTS, INCLUDING DRIVESHAFTS, CAN FAIL, CAUSING INJURY OR DEATH. DO NOT FOLLOW THESE DIRECTIONS EXPLICITLY. NOBODY SHOULD MAKE THEIR OWN DRIVESHAFTS. SEE A PRO TO HAVE ONE BUILT.

I cut off a piece of the donor shaft a couple inches longer than needed.

I used a work table to mark the exact C -C length that the shaft should be, using the edge of the table as one center point and measuring the other center length from the table edge.

I used that line to place the cut yoke and marked where the final cut should be.

I wrapped the shaft with a piece of paper such that the ends of the paper align perfectly. That will give a square cut.

I carefully cut the tube to length. Roll the tube into the saw so only the top edge of the tube is cut.
After cutting de-burr and square off perfectly in a disc sander.

Use two pushrods inserted into the bearing bores to get perfect end alignment. By lowering my sight line to the point where the farthest pushrod ends disappear simultaneously I have achieved perfect end alignment. It may be necessary to whack the lose end with a brass hammer to align the loose end. It is a snug fit in the tube.

Press the ends together for a perfect alignment.
One final check for fit before welding.

 

Question?
Does parallax error still exist while lining up both of the pushrod ends on either side of the drive shaft by eye?
Or is it close enough that it is negligible?

 

I think it would be negligible. I suppose if you backed off many feet and used a telescope to watch the white ends disappear it would be incrementally better but frankly it is not necessary. Another consideration - if there is to be any alignment error it may be better to err on the side of having the drive end a teeny bit retarded so torque input causing any wrap-up would tend to make that error diminish.
But its angels-on-the-head-of-a-pin. Its fine.

 

Thank you for answering my question.

 

Carpenters call them winding sticks, don't ask me why, cause he don't know. (HAIR playing in the background).

And you're right, it isn't a recommended method of driveshaft manufacture, and it was desperate times.

Hey, young and dumb...

 

I've found that just laying the yokes, holes vertical, on my steel table will phase them close enough.

 

Has anybody had good luck painting brake drums? What method works? These drums will be seen through the wire wheels and I want them to be as inconspicuous as possible.

 

when shortening a driveshaft i align the yokes by pressing in a ujoint cap allmost all the way i leaving a slight amount sticking out then use an angle finder or a good level on the cap to match the two ends at zero degrees

 

Hamber “mrmodelt” has model t project on here “a new project a-tv8” painted drums with plastic coat engine enamel says good to 500 degrees

 

On the Belanger Special baking plates and drums are painted chassis color. VHT caliper and brake drum paint good for 900 degrees. I guess it might depend on your chassis color and paint scheme,

VHT Caliper Paint -- High Heat Coatings (vhtpaint.com)

1930 Belanger Indy Special | conceptcarz.com

 

1930 Miller


1946 Kurtis NOVI


The Brumos Collection | Conceptcarz.com

 

Thanks AmishMike and HJManiac. I looked at both - and also Por 15(good to 350*) and also Rustoleum caliper paint (good to 2000*!!!). The drums will probably end up chassis color - either semi-gloss black or aluminum.

 

I completed construction of the driveshaft. I ground off the parting line flash on the yokes and ground off some of the balance weight, thinking that if that balance weight was needed for a 4 ft. long shaft that considerably less weight should work for my 12.25 inch shaft. Then I welded it up and installed new U-joints. I elected not to use heavy duty U-joints. HD U-joints do not have provisions for a grease fitting and being a traditional rodder I prefer to grease my shaft as needed. I did make sure to install the U-joints so the Zerks were placed in compression - not tension - when accelerating. They will take more abuse that way. Since I am not using a clutch or a transmission brake the standard Spicer joints will do just fine.



As soon as my new replacement axle comes in I will now have a functional driveline, assuming the used C4 trans I acquired is as good as stated by the PO.

 

That is a short shaft!