Iam trying to raise the frame over the rear in the SUB-to lower it.I usually use 2x4rect tubing- but in a pinch here weatherwise and moneywise-so I wanted to use what I have. I cut two places in top of frame and bent a peice of 2" round x3/16"wall pipe in an arch to form the raise section. my question is this-If a standard Cknotch is adequate then would this be just as strong or am I missing some stress force point that is blowing by me?[I plan to flat plate the frt and rear]-joints where the pipe is welded top and bottom to old frame.My point here is will the two uprights at rear and diagonals in front of the "U"KEEP THE FRAME FROM FOLDING OR TWISTING?.....I plan to tow like 2000 pounds at most and prob wont haul more than for people.Oh I forgot- drivetrain will be stock 99Vortec 350 and 400 turbo/9" rear..Thanks and let the criticism begin...... ...........[I can take it!]
When I look at it I see a triangle without a bottom. The bottom is the leaft spring, and as you know does not offer any strength from the two parts coming together because of the shackles. So everything appears as though it is relying on the strength of the tubes at that point in which you welded the tube crossmember across. You might want to wait until you can get the 2x3 that you're used to using. What kind of vehicle is it? Sam.
Its a 58 suburban- I want to keep it from protruding any higher into the floor Sam- I am going to put the rear on top of the stock l;eafs....I have seen a hundredcars and pickups with the frame cut clean to the top of rail and just a flat 1/4" peice c-shapet to reconnect them and they get by with that!-I kinda think it WILL work. [but I am] willing to listen......
another point- wouldn't it "pull"or stretch the leafs if it were in a fail situation?also wouldn't the actual quarterpanels/body structure add to the frames rigidity?they -by the way are not just a skin- they are all inner paneled the complete length with a stamped 16guage inner boxed re-inforcement.[not at all like a pickup bedside is/ just an outer skin mostly]
I'm sure it will work choprods. I guess I tend to overengineer stuff... and when you said 2000 pounds, I was thinking pickup truck! Have you figured out how much travel you'll have and need once the axle is on top? the higher you go with the tube structure, the weaker it will be. Sam!
you idiot! your such a moron. and UGLY too!! hey you said you could take it! as for the C-notch, i don't think i would trust it. especially on a big ole Suburban. i'd maybe go with 2x3 3/16 or 1/4 wall and with carefull measuring you should be able to build it so it takes up a minimum of floor space. it just seems to me it would want to fold right there and though it might not catastrophicaly fail it might cause some tweaking in the body and mis alignment of the doors and such. i'd get ElPolacko to take a look and get his input. i've done alot of chassis work but he is a real pro. drop him an email and make sure he sees this thread. Mike
i have mixed opinions on this the triangles do help alot .it looks strong enough to hold the cars waigth .but i think if i were planing on towing with it id probally do a little more reinforsing on it .2000 pounds is alot of waight on a c notch.but thats just my thoughts .later kyle
This is the guy that helped me bag mine and whos going to c-notch and 4-link my rear......send him some pics and see what he thinks. This guys VERY good. He has pics of his work....... http://www.intensegravity.com/kaltrendz/index.html
I think all your good for is about 4 cubic yards of crushed rock at a time,Just dont raise the box more than 5 feet when ya dump it.OK just kiddin Ide guess thats WAAAAY stronger than a c notched rectube.---Feder
I wouldn't trust it. If you had attached the front inner diagonals to the BOTTOM of the front rails you would be a little better, but right now, all the bending is taking place right where the C tube hits the top of the stock front frame and I don't think it will last. After the rear is relocated upward...can you just add some round tube below the rearend? Engineer it to be removable with welded on exhaust flanges (like if you were making a tube tranny crossmember) so you can change the rearend if you ever need to. Bill
sorry-1 LOW,But I'd sell this before Id do that...... Bill- that IS a good Idea...Sam I have 5" travel after the rear is on top of leaf-with 3" blocks
[ QUOTE ] sorry-1 LOW,But I'd sell this before Id do that...... Bill- that IS a good Idea...Sam I have 5" travel after the rear is on top of leaf-with 3" blocks [/ QUOTE ] I hear ya man. I figured it was just food for thought.....
If you have any more tubing, what about bending a peice to fit inside that peice, and go to the bottom of the original frame, then stitch weld the two tubes together.
I've seen a lot of sport trucks and imports done in a similar fashion, but I can understand what Sam is saying... Seems like a lot of stress to put on that single piece of tubing.
What about the factor of the floor and body structure I mentioned?I would think this would be as strong as an s-10 with a c-knotch the full height of the stock frame rail- mainly supported by the bed floor above it?I could plate the frame where I intended to and make that plate extend upwards to encompass the front of the"U-TUBE"...........
Under a load, the pipe will want to collapse. It cant be as strong as rectangular tubing that is placed on its edge. Dan
I think you could modify your current set-up a little bit to get more strength out of it. Why not run the "diagonal" support tubes from the CENTER of the cross tube to the BOTTOM of the frame? Then run only one "upright" in the rear down the CENTER with 2 more "diagonals" running from the center of the cross tube out to the top of the frame... The "uprights" in their current configuration don't seem like they offer alot of support, other than shoring up the "diagonals" on the other side. In the set-up I described, (assuming you can even understand my description) the "diagonals" would offer more support on the front side and would still have the shoring from the one "upright" in the rear. But there would be added rigidity from the 2 extra "diagonals" in the rear. Did this make any sens at all??? I'm assuming you're going to run more or less stock suspension here, right? No airbags, or hydraulics, or anything...
[ QUOTE ] Under a load, the pipe will want to collapse. It cant be as strong as rectangular tubing that is placed on its edge. Dan [/ QUOTE ] Correctamundo! Tubing WILL NOT resist bending as well as rectangular tubing. Place a 5 lb weight on top of a 3" corrugated cardboard tube. The weight will crush it. Take two flat pieces of 3" wide corrugated cardboard and place them upright and parallel to each other. They'll support the 5 lb weight.
I could be wrong but it looks to me that the center section will bottom long before the axle tubes. Why dont you just remove the springs, lift the axle untill it bottoms at the center section. Then you can cut a plate and weld it inside the U bend as much as you have clearance for. You could even intergrate a bump stop there. Then it would be strong enough for sure. Just my 2c.
IF I put housing on TOP of stock springs with three inch block it will lower the truck 9".that will leave 5" travel[up] at the "pumpkin" [where it would hit/IF]....thats enough.-Here is what I did today I boxed the frame-tube joint front and rear with 1/8" plate.am I good now?
Keep it as is, but bend up another C-shaped tube that fits over or under the one that's currently acting as the frame rail and then box the sides together with some flat stock. That should be more than enough to handle towing 2000 lbs and the weight of the Suburban. As it currently is, I wouldn't trust it under the weight of the car when loaded and driving down the road, let alone towing a 2000 lb load. I prefer to play it safe and over do it than be sorry later.
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