Installing a C-Notch

[Ricos54]

Looking good Rico.

I'd like to model the diagonal link in AutoCAD Inventor and run a stress analysis on it, just for $hits and giggles.

I've read some negative stuff on the internet about using diagonal link on the street, like here: http://67-72chevytrucks.com/vboard/showthread.php?t=187382

But I also see a bunch of folks selling them for street use.

To me it just seems to reason that with the long diagonal bar there should be some pretty large loads at the ends of the link, and pretty large buckling loads on the link itself. I've been wrong many time before though (ask my wife) so the analysis should help me wrap my head around what the loads really are.

If you're up for it, could you get me some dimensional information on your rear suspension?

A (see photo below)= 29"

B (see photo below)=26 1/4"

C (see photo below)= 35 1/2"

D (see photo below)=9 1/4"

E (see photo below)=6 1/4"

Four link bar diameter =1 1/4"

Four link bar thickness = guessing 1/4"

4 link no HEIM JOINTS all polyurethane bushings, Bushing thread dia. 5/8" an bar hole 5/8" and only one side adjustable which is at the rear end,

Four link heim joint through bolt diameter = N/A
Four link heim joint thread diameter = N/A

Diagonal link bar diameter =1"

Diagonal link bar thickness =1/4"

Diagonal link heim joint through bolt diameter =1/2"

Diagonal link heim joint thread diameter =1/2"

Thickness of diagonal link bracket that attaches to four link bolt = 1/4"

Man Roadster your killing me with this stuff!
Also I'm not building this truck for hot rodding, I'm building a nice street Rod and building it to get good gas mileage. So NO Burn Outs, no driving at Mach 1, it's going to be a cruiser.

 

[Lakeroadster]

Sorry Rico, Don't mean to stress ya out. I'm just curious about cornering loads. The 4-link is no doubt bullet proof in regards to launch and braking.

Guys it might be this weekend before I can run the analysis... hang tight, I'll report back!

 

[Ricos54]

Sorry Rico, Don't mean to stress ya out. I'm just curious about cornering loads. The 4-link is no doubt bullet proof in regards to launch and braking.

Guys it might be this weekend before I can run the analysis... hang tight, I'll report back!

I know, no worries. I feel I made the right choice. One of the things why I picked this setup was for the adjustability. I can move my pinion angle up or down I can make my wheel base longer or shorter and I will have more wheel travel with this setup.
Edit: by my calculations at ride height the diagonal bar will be level

 

[Lakeroadster]

Using the data you provided above I created a model of the 4-bat and diagonal link. I then did Finite Element Analysis on tjust the diagonal link and it's brackets.

For the side load I used a 4600 lb side load (Assuming a loaded 54 Model 3804, think power sliding around a corner fully loaded , a worst case scenario.) Everything seems to be fairly low stresses with the highest stresses being on the diagonal link bracket that attaches to the rear lower four bar. About a 5:1 safety factor fully loaded.

I then used a 1800 lb side load (assuming an empty truck) and that results in a 13:1 safety factor.

Left hand or right hand turn produces the same stress results... the diagonal brackets govern the analysis.

Conclusion: Based on the above it looks like the diagonal link is an excellent design for centering the rear axle.

Model of the 4-Bar with Diagonal Link

​

FEA Model of the Diagonal Link (showing exaggerated deformation, actual deformation is minimal). Disregard the 4-bar link on the left. It is needed in the model to guide the end of the diagonal link.

​

 

[Ricos54]

Well, based on my analysis it looks like that diagonal link is an excellent design!

Well, that's good to here. I can't wait to get it on the street and see how it handles in real world driving

Thanks Lakeroadster

 

[Blueflame236]

Bed upgrade

Rico , Lakeroadster

Very intresting topic presented by all you guys.I wanna thank you fore sharing.

A quistion to Rico
I Wonder if your bed is going to be build higher up then standard sinds the c-notches are that high ? Do you considder of installing air suspension ?
Found Frank the italian`s Upgrade for you to watch , ; http://www.jalopyjournal.com/forum/showthread.php?t=568254

Martinius.

 

[Ricos54]

Rico , Lakeroadster

Very intresting topic presented by all you guys.I wanna thank you fore sharing.

A quistion to Rico
I Wonder if your bed is going to be build higher up then standard sinds the c-notches are that high ? Do you considder of installing air suspension ?
Found Frank the italian`s Upgrade for you to watch , ; http://www.jalopyjournal.com/forum/showthread.php?t=568254

Martinius.

Thanks Blueflame, yes I have considered bagging my truck. One reason I left the c notches so high, this way if I decide to bagged at a later time it's already setup up for it. Also it is higher than the standard bed so I will have to raise the bed around 2". I don't think it will take away from using the bed as a truck with only raising it 2". Also I have seen Franks truck, it's one bad ass looking truck.

 

[AZbent]

Make sure the bolts for the PHB are pointing down (bolt head on top). If by some chance the nut falls off then you will not lose the bolt holding it in place. The bolt should extend beyond the nut after tightening at least one full thread for the nyloc nut feature to be of maximum use. Other than that it, looks really good and you should be proud of it. when it is complete, show it off.

 

[Lakeroadster]

Good point, fasteners should always be installed in this manner, when it is an option. Learned that in Vocational Agriculture class, learned more in that class than any other I ever took.

Oh, for the record, it's a DL not a PHB.

Assumptions:

• PHB = Panhard Bar
• DL = Diagonal Link
• And that texting has ruined the "written word"

 

[Ricos54]

Make sure the bolts for the PHB are pointing down (bolt head on top). If by some chance the nut falls off then you will not lose the bolt holding it in place. The bolt should extend beyond the nut after tightening at least one full thread for the nyloc nut feature to be of maximum use. Other than that it, looks really good and you should be proud of it. when it is complete, show it off.

Thanks for that info, I was figuring on putting the bolt the other way thinking the head of the bolt would be flatter underneath giving more room for space to the ground and thinking those type of nuts would not come loose. Better safe than sorry, so thanks for that.

 

[AZbent]

That is what we teach our students that want to aircraft mechanics. the correct direction of bolts and hardware, etc.

 

[Ricos54]

Received my 22 gallon aluminum gas tank today. I haven't installed it yet, but this is where I'm going to put it

 

[Blueflame236]

Reinforced rear end parts

Rico

The tank is nicely Integrated at the back side. Do you plan to Connect the filler neck on the rear side of the bed ?

Can i ask you if the parts your using to reinforce the rear end is a ready to install kit or did you manufactured them your self ? In case this is a kit where can you buy these parts?

Apreceate the information Martinius.

 

[Ricos54]

Rico

The tank is nicely Integrated at the back side. Do you plan to Connect the filler neck on the rear side of the bed ?

Can i ask you if the parts your using to reinforce the rear end is a ready to install kit or did you manufactured them your self ? In case this is a kit where can you buy these parts?

Apreceate the information Martinius.

Thank you Blue, still trying to decide wether to have the gas cap integrated in the bed or to run it to the side wall behind the rear fender. As far as the rear end if I understand your taking about the part that the gas tank is resting on. I took the stock crossmember out an added a 3" x 3" square tubing which is a 1/4" thick to reinforce the back of the frame.

 

[Blueflame236]

Reinforcement

Rico
I ment everything you have done really . Is this a kit and where can you buy it from ? I have one moore question; how do you plan to Connect the rear axle to the frame ?


New rear end open axle , what year ?
Suspension and Connection bar?
The 4 link and diagonal bar?
The Panhard bar?
The bar where the exhaust pipes go through ?
Bar Connected to the C notches ?
C notches ?

Martinius.

 

[Ricos54]

Rico
I ment everything you have done really . Is this a kit and where can you buy it from ? I have one moore question; how do you plan to Connect the rear axle to the frame ?


New rear end open axle , what year ?
Suspension and Connection bar?
The 4 link and diagonal bar?
The Panhard bar?
The bar where the exhaust pipes go through ?
Bar Connected to the C notches ?
C notches ?

Martinius.

The axle came out of a 71 Grand Torino which is a ford 9" posi 300 gears.
The 4 link & brackets, crossmember and diagonal bar is one kit from a company called Danny's Original Customs in LA you can look them up on the internet.
My shocks are competition engineering, top of the line shocks with 12 positions adjustable coil overs
As for as the exhaust go's I will be taking my truck to a muffler shop and they will install the exhaust. For mufflers I'm looking at Borla
The c notches came from a company in town called KBS in Oroville.

If there's anything else, just ask!

 

[Blueflame236]

Thanks so much for the update.

I looked it up and found the EBAY site With 4 link kit fore 495 dollars.Does he have a store in LA ?

Martinius.

The axle came out of a 71 Grand Torino which is a ford 9" posi 300 gears.
The 4 link & brackets, crossmember and diagonal bar is one kit from a company called Danny's Original Customs in LA you can look them up on the internet.
My shocks are competition engineering, top of the line shocks with 12 positions adjustable coil overs
As for as the exhaust go's I will be taking my truck to a muffler shop and they will install the exhaust. For mufflers I'm looking at Borla
The c notches came from a company in town called KBS in Oroville.

If there's anything else, just ask!

 

[ol' chebby]

I ran my filler into the driver's rear fender with a stock cab and filler rubber grommet.

 

[Ricos54]

I looked it up and found the EBAY site With 4 link kit fore 495 dollars.Does he have a store in LA ?

Martinius.

No store, just his shop. Shoot him a email and tell him Rico sent you. He will answer any questions you have. Also he has 3 different 4 links so you can pick what will best fit your needs.

 

[Ricos54]

I ran my filler into the driver's rear fender with a stock cab and filler rubber grommet.

I remember seeing it in one of the pic's of your truck. I mounted the tank today and the gas hole is right behind the tailgate in the middle don't know if I can turn it 90 degrees to go to the side or fender. Might have to go straight up through the bed. I'll see when I get close to that project. Right now I have to finish the mount for the tank then it's time to build the bed floor up about 3". Thinking about building a tilt bed floor like Frank's truck on the other side of the pond.

For now here's what I did for mounts for my gas tank. It's not done, still have to put a bracket in front, behind the rear end to box the gas tank so it's supported on all 4 sides.