It's time to build a new frame for my 54 chevy truck. I've had plans to build new bones for it, for a while. After seeing some of my fellow hamber build up some awsome frames, I had to get in there and see what I can whip up in the shop. I am using 11ga 2x4 tubing and 11ga flat stock for the frame. Custom rear notches, and a 57 bel-air rearend, with a custom truck arm based rear suspension setup. Air bagged mustang II setup up front, to lay the running boards flat to the pavment. The plan is to use the frame as the air tank, for a ultra clean look, and that lil bit of wow factor. Hope to get a few more hours in on it tomm. nite and get the rear rails ready to weld up Saturday and have this thing looking like something.
Got a few more hours in on the frame today, let me know what you guys think. working on the rear cross member added a peice between the rear notch and rear crossmember I still have a long ways to go on this thing but its starting to look like a frame now, instead of a big pile of tubing and plate.
I got the front half of the frame tapperd like the factory redsigned and fabbed up a new core support crossmember and started transplanting the cab and running board mounts. let me know what you guys and gals think.
Starting to look like a frame now. I got the mustang II finished up, all the running board brackets transplanted, and started setting up the rear suspension. Gonna get the other link bar finished up this week and start designing the rear bag setup.
Beautiful workmanship. Just one concern; those rear radius 'truck' arms......they appear to built of rigid tubing. If so, something might break. The rear axle needs to rotate freely about the center of the ch***is without binding. That setup looks too rigid. Maybe I'm just not seeing it in the pictures though.
Its not really a truck arm setup, just a simple 2 link with a panard bar, setup for bags. Ive used this setup before on a few different rides and never any problems
Looks good mate, It might be the angle of the picture but are you sure you have the top hats on that Mustang II setup round the right way? Just looks the are pointing down towards the front of the ch***is, for the anti dive to work correctly it should be higher at the front.
Nice work! Thinking about setting my 49 up like that . Jimenezbroscustoms.com has a two link setup . I want to get my truck setting on the running boards . Not sure of what setup to go with , do you have to modify the frame using a mustang 2 suspention to get it that low?
Its basically the exact same trailing arm system 60-66 and 67-72 chevy trucks have from the factory thats worked for years.... Great Job I Like it!
The only modifiying you have to do is remove the factory I beam and springs, of course, box a section of the factory frame and install the mustang II per the instructions in the kit. I have seen a few that had to notch out for the tie rods, but I havent gotten that far yet.
Starting the rear bag setup this week, here is the progress so far. Hope to have it finished by the weekend.
Yes....and an emphatic NO! This setup has been the subject of lengthy threads here. The primary error in the setup pictured, as someone else mentioned, is the very rigid nature of the control arms. The GM setup worked well ONLY because the control arms were able to twist along there length. They were two "C" channels, back to back, forming a sort of "I" beam. Any round, square or rectangular control arm, when rigidly mounted to the axle housing, will stress the joint at the axle housing when ever there is any significant body/ch***is roll. And ch***is roll will be limited by this setup, though improperly, because it in effect makes the axle housing a very large and stiff anti-roll bar. You may very well have used this in the past, as have others, and gotten away with it. But that comes at the expense of improperly limited suspension movement by the forces described above and/or breaking the weakest link when the suspension tries to articulate. You may notice I was an early poster complimenting you on your workmanship. That still stands. What I am calling into question, for your benefit, not mine, is the error in 'engineering' this represents. It's not too late to correct it. You would need to subs***ute flexible control arms for what you have now. The forward ends also should be much closer to the center to minimize undesired forces, but you probably could "get away with" the spacing if you use the correct arm materials. Ray
For more input on this subject, see the current thread "TECH: Mounting rear radius rods". Slighty different style but same geometry issues........ Ray
Not auguring your statement since im no engineer and have done no research , but know that suppliers cpp,porterbuilt,brothers, of 60-72 trucks offer tube and rectangle trailing arms as replacments and many(alot) of guys on the chevy truck forums run them and there hasnt been any problems on daily drivers,, like these: http://www.customcl***ictrucks.com/...prises_trailing_arm_kit_install/photo_01.html http://www.cl***ictrucks.com/tech/0701ct_early_cl***ic_trailing_arm_kit/photo_01.html http://www.porterbuiltfabrication.com/showthread.php?251-Tubular-Trailing-Arms-499 http://www.cl***icperform.com/Store/1960_1972_Chevy_Truck/6372TRS-K.htm http://www.brotherstrucks.com/prodinfo.asp?number=RCA72TB http://www.cl***icindustries.com/truck/parts/tta6072.html and the links go on and on...... Its easy to say it will or wont work and diffrent when it does or doesnt when its installed.... If its been done and with no problems i think it works personally but thats each owners personal call and just my opinion! Didnt mean to hi-jack your thread , back to the build!!
LostHope...I fully expected replies such as yours. I am well aware of the many kits offered that use tubular components. And they work...sort of. But they also have their shortcomings. The fact that using such components, or any other not quite right engineering, doesn't cause the Earth to open and swallow the miscreant who dares violate the Laws of Physics does not mean they are correct. It only means that the result will be less than than optimum and how much less will vary by degree with how far off the design/materials are from correct design. People are relatively free to do what they want......including ignoring 'best practices', but if you/they are going to invest time, effort and money in a project why not strive to get the best result possible, especially when there is little, if any, extra cost involved? Ray
Same basic design that is used in stock car racing with the exception of the air bags I would say if they can run it @ Daytona running 200 mph it should work on the street
"The Devil is in the Details" I could be mistaken, but your post suggests you didn't read previous posts...... Your are correct that Nascar has long used the GM truck arm arrangement. In fact that's where I got mine...from Stock Car Products..they make new ones and they are very much like the GM design but for a few very minor details. The main trait of the GM units, the "I" beam style is what they produce and is used in the Nascar setups. By the way, Nascar setups also keep the forward ends of the arms very close to the center, not spread out. So, thank you for helping me make my point. Ray
I think alot of the design that I along with others that choose to use a setup like this, depends on how you intend to use the vehicle when done. I am not building this thing to do 200 mph laps at Daytona, or to go rock crawling where alot of articulation is needed, or do I intend to do any auto crossing in it when done. I am building this to mainly show off my fabrication and paint and body skills. It will NOT be a daily driver and I intend to drive it on weekends and drive around at some shows everynow and then. The air ride setup will be limited travel with only front and rear up and down, NO side to side action. So I really don't undstand why so many people have problems with this type of rear suspension. Like I said, to me it depends on how the vehicle will be used. Now I have gotten a lil more done this week. Still working on the upper bag mount crossmember.
I believe you make a valid point and I agree with you. For use within the limitations that you describe, there will be no functional difference. My later comments aside, I still congratulate on your skill and workmanship. Regards, Ray
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