Need to prove to inspector that 34 axle is strong!!!

Oh yeah, I want it be fenderless and have open headers!!!

Both of which are illegal in this province. hahaha!!!
Honestly tho, I'll probably have to run some kind of knock off exhaust and "quick release" motorcyle fenders to stay fine free.

 

Then it looks like the big issue is the dropped and drilled axle. Or the inspectors impression that it may not be up to the task.
You may be up against the wall on this one. Even though many of us run/have run dripped and or drilled axles it may be hard to show that the have the necessary strength. If I were in your shoes I think I would invest in a new dropped axle from a well known and respected manufacture and run it, at least through a couple of inspection rounds.
I know that isn't what you want to hear and it would always be the part that isn't quite "old school". but it should satisfy the powers that be and let you get on the road.

 

One good point I did get by phoning Dave Mann, (roadsters.com)...who does an amazing job dropping, drilling, and polishing axles, was that this axle was also engineered for and used on the 1 tonne ford PU's of those years.

A documented ford factory fact!! Not just a common knowledge hot rodder fact....because, as we've all concluded, we're not dealing with a hot rodder here.

In addition to being inspired by Dave, I also learned of a cool historical hot rod fact that I didn't know until I talked to him; that the drilling process did not originate from speed racers trying to lighten their cars....but from early track racers trying to allow the axle to twist a little more under turning forces and give added traction, instead of wanting to lift, resulting in a lack of traction.

Maybe everybody knows this already??? hahah. I donno, but I thought it was pretty cool.

 

48Chev,
In my opinion, and from reading some of the horror stories on here...I think most aftermarket axles are not really the safest things to run....ductile iron that's alot more likely to be a problem than any stocker .

If anything I'll run my straight model a stocker, or try to get a hold of a Chassis Engineering forged axle.

 

Bruce brought up a really good point about taping the axle too. Before we read Bruce's reply, my buddy and I fluked into figuring that out yesterday when we painted the axle. We had the inside masked off for painting the rest of the axle....and honestly man....you could toooootallllly pull that off! hahah. Shot of high build prime and a shot of tremclad black...and you're off to the races.

Thanks again Bruce, you've been super helpful. I'll make sure to post some pics of the progress.

 

I'll make sure I don't stir the waters too much so there's no extra attention on you when I ask around.
By the way.. there are lots of us "Blue Nosers" on here.
Go to google and type the following line:
scotia site:www.jalopyjournal.com
You'll see a fair number of hits.

 

"I think most aftermarket axles are not really the safest things to run....ductile iron that's alot more likely to be a problem than any stocker . "

Here's your paradox! I agree 100% on this, and believe cast repro axles are for streetrods that function basically as life size scale models of a car. Just the act of duplicating a forging in cast means your design is FUBAR, because you'd want to use different sections and more metal around the pin holes and so on if you were DESIGNING an axle as a cast part.

But--the PARADOX: If you use a streetrod cast axle, the engineer can call them and talk to their dude who will say "XXXstrength per inch, 10,000 sold with no fatalities rolling off the trailer, etc."
The Ford axle is most likely MUCH stronger, but the strength and durability of dropped axles is folklore from a disreputable antisocial hobby, not engineering data. WE do have Ford strength data, but engineer can and will reject that because dropping obviously disrupts the nature of the steel there. So, fraud time!

 

Would it be easier to 'import' it? Have it registered in, say, the US of A somewhere, then show up with a valid title and reg, and a bill of sale maybe? Is it the same inspection process? There has to be a state in the Eastern Corridor somewhere that has a reasonable registration process.

Obviously this would be a MASSIVE P.I.T.A. . So I would definitely try whatever you could to get the engineer to 'buy off' on your car and only use the 'import' path in case he won't.

FWIW Lightening holes in aircraft structure are more than just holes. If they are in a single thickness they will normally have a flange of some sort around them, it acts as a stiffener. If they are in a piece with more than one thickness, they will usually both have a flange, or only have the hole in one thickness.

If he doesn't believe aircraft take forces from multiple directions at the same time, or take torsional loads well, have him take off out of LAX in the back of a Lockheed L1011.

 

maybe you should just ship your truck to BC and have it inspected and regestered, then drive it back home.

 

I'll keep this short but we had some argument with our authorities here in our country last year. Now it seems that we have to start using fenders and four links. I just replaced the -32 split wishbone with four links in my Model A Coupe.

Anyways, this is what one guy calculated on another forum. Sorry for measures in meters but I already translated that in English and its getting late...


Hypotheses:
- split wishbone or hairpin, length 900mm
- suspension movement 100mm (the largest distance betw. upper/lower point)
- angle for wishb./hairpin = arctan 0,1/0,9=6,34 degr.<WBR>

So that's the max. angle for axle.

- The dist. between perch bolts in I-Beam 92,71cm

- Twist 6,34 degrees per 92,71cm means 0,006839degr. /mm

So the same twist is between the perch bolt and the hub (13,5cm), for example when braking, it would then be: 0,006839x135=0,<WBR>923201 degrees.

So I-beam twists 6,34degr. on the length of 92,71cm for example when you drive over the curb.


Now, the next calculation should be: How hard to brake so that the same twist occurs between the perch bolt and hub. This is where the calculation ends by now. Very likely you will lose the traction under the tire before breaking the axle... But please go on...

- distance 13,5cm
- twist 0,923201 degr. (situation remains the same than above)
- moment needed from the brakes? (alfa=T*l / G*Iv)


And yes. I am an engineer. I think he is one too...


Later,
--mika

 

Hey Mika,
Thanks for the formula. I don't mean to be rude but could you break it down in leighmans terms a little for me to understand.

Does that formula say that the original axle is fine? Or that it's not fine?

Is that saying that the amount the axle twists depends on the lenght of the wishbones? Like longer means less twist? or the opposite.

Is twisting a bad thing...or should it help to maintain traction?

I'm confused that's all....haha.

I'm not an engineer but I fully respect and appreciate anything that can be proven with numbers.

Thanks Mika!

 

Yes. no problem. First, I have to say, that the calculation ends too fast, there's some more we would like to show to our authorities here, but that's another case.

The calcultaion above was made to give a hint how much the I-beam twists when using a split wishbone or hairpin. And that was because they are pretty much considering them illegal here nowadays.

So, the conclusion was that a forged axle, made to twist, should be fine with that twist what split wb/hairpin causes.

And the breaking moment calculation (unfinished) was meant to show the possible twist when you hit the brake. In the other words, how hard to brake to achieve same twist that hairpin causes...

Anyway, any engineer office can make these calculations, but I would like to believe that Ol' Henry's people have done it right in the very beginning... How ever they used a wishbone with ball which makes the case different. Also Your case, axle with holes, is a bit different. So I'm not sure if this helps you at all. In our case we still keep trying to proof that all professionally manufactured / tested / proofed hot rod parts should be accepted with no calculations or explanations.

--mika

 

Just as a note that no one has touched on -- for everyone who keeps saying to take it to another province or the states to be registered titled etc. -- because every province in Canada has its own legislation regarding this it wouldn't make a difference. It would still have to pass an inspection when he attempted to switch the registration to his home province. There really aren't any loopholes on this one. Definately seems like you guys have it really rough on the East Coast.
Regardless I think you are in for a fight on this one. But I do agree with everyone else about the straight axle technology -- the fact that brand new trucks are rolling off the line today with them really doesn't back up his "piss poor" argument.

 

SOunds like sitting down in neutral territory like a restaurant and having a cup of joe with the guy may help. Take a notepad, ask questions, put the ball in his court so he has to back up his side. Look at your Provincial vehicle code ahead of time, learn it, bring a copy with for him to help you makes notes on it. Like Swayze said in Roadhouse "always be nice!" (at least to someone who has your balls in a vise)

One thing, open headers on a daily will get OLD real fast, give your neighbors a break and run an exhaust.

 

my point about using a different province is it would take you down a different road when you returned to NS, i'm quite sure your car would pass inspection here in BC with split bones, then when you went back to NS you would not be dealing with a provincal engineer, just your local service station guy for an inspection, and i think you have 6 months to do that even, as for new trucks that have straight axles well they have parallel springs and they twist the axle very little if any, non split bones twist the axle very little as well, if any. a little story about me in NS back when i was young, i had a 46 chevy pickup with about 2" trimed off the bottom of the rear fenders, i was pulled over and had to install mudflaps.

 

There's twist and there's twist...whole axle twist is caused by differing inputs from split wishbones forcing the axle to act like an anti-roll bar...a wishbone moves as a unit and inputs no twist. How much do fourbars put in? Half of split wishbone or so?
End of axle twist is a separate thing. There are lots of different forces here, but main twister would be brake input forcing axle to twist at drop...I don't remember if I posted this above, but Ford engineering 101 book from 1935 discusses this: resistance (like braking input to axle) is multiplied by amount of axle drop. This is what is likely alarming the engineer...dropping axle simultaneously weakens the axle right at the weak point by damaging its original heat treatment while the greater lever distance provided by the drop increases the force of twist. A typical Ford dropped axle very roughly doubles the drop and hence the twist...and the extra twist is actually visible on open wheel cars. Only the great remaining strength of the forging saves its ass.

 

Bruce is square on with his statement on heat treating, and the effects of the drop process. And say that to the engineer and you have no chance. And its true he has all the documentation theory to prove his side. BUT the one way to counteract theory is with documentation of your own. And if you are set on that axle, your course of action is this - find some one that will do non-destructive hardness testing on the axle. It might take some hoops to jump, but it might be worth it. Best yet, find a local college/university with Mechanical engineering program, and hit up the program, with doing a study on your axle. Course work is always looked for. What you'll get - A metallurgical and stress study of your axle, with documentation, for little cost. (But might not be a quick process) Mech. labs are always looking for material subjects for their courses, and you might help to get some documentation on the table AND clue some future engineers in. Just a thought

Or you could get the tech data on new repro axles, as they need to be documented. And the process is basically the same (or at least you MIGHT be able to pass it off as such). But this would take some finesse and diverting his attention. A little press of luck.

 

Hey Stevie. I told you I'd get some local info as soon as I got feeling better.
Yesterday my heart started beating in time again (need a new distributor or maybe adjust the "dwell") so I took a drive and had a chat with a local rodder/builder. He was stunned that a forged straight axle would be questioned if it was setup to standard configuration. However, he expected that a tube axle wouldn't cut it with them.
This guy has his inter-provincial mech. ticket and swears that he found no reference in the DOT books that an engineer is needed to inspect for insurance.
He has been doing them for years. Usually uses a solid, forged axle though.
I've known this guy forever and I'm tryin' to get him on the HAMB (doesn't have a computer.. he laughs proudly and says he still has a rotary-dial phone). This guy is a true HAMB/old school type. I've always respected his talent and work.
I looked at a custom he's been working on for a client for 4 years (while doing other jobs in his shop). Classy work.
As I walked into his shop I was faced with 2 flatheads on stands and another in the custom. He's passionate about flatheads and it shows.
Anyway.... If you are still having issues PM me and I'll try to get you two in touch. Maybe it will help.. maybe not.

 

If hes anything like the fuckwit engineers we have here in Oz, then tell him to get stuffed coz he obviously doesnt know shit about cars.

Seriously, get ANOTHER engineer coz this guy sounds clueless. Been there DONE that...TWICE !!

On a lighter side, I have I beam axle specs stashed somewhere that should come in pretty handy and would prob solve the problem with this pinhead engineer.

PM if you are interested !

Rat