tube chassie help

[onekickkawi]

i have been thinking about taking my car a step further and tubing the front end... problem is i dont really know how to approach fusing the front end to the body (its a UNI body) so im just wondering if anyone knows of any site that discuss it. thanks a ton in advance

the car is a 1972 510

[zapster]

I think "tubing" the front end is a waste of time if you don't have sub frame connectors and a cage to tie into already installed..
There are pre fabbed bolt on kits out there also..

ZTFab would be more help here seeing as he does this all day every day..


...zap!

[Rojodiablo]

I agree with Zap. If you don't have tube running from stem to stern, any part of the tubed front end you build will not add any real strength. In Jeepspeed racing, they work with cherokees that are uni-body. Also, Nissan Pathfinders?? Exterras, and definitely Toyota land cruisers are unibody. I have seen where the cage ripped itself out of the body inside after a hard run in a jeep. So, you will need LOTS of contact points from the tube to the body. I mean dozens.I would check Jeepspeed for their input.

[onekickkawi]

i have a cage inside the car now but i would like to expand to the front end.. and eventually the rear. the car came with a 92hp 4 cylinder engine originally.. i fabbed somemountts up and its running a large v6... i want to take it a step farther and put a LS6.. A LS6 from a corvette is ideal because the tranny is in the rear, so i wont have to buy a new rear end and it will even out some of the weight differneces

[ZTFab]

You're going to want to tie the front end into the existing cage but what we need to know is how many "points" does your cage currently have?

Is it an actual cage or just a roll bar?

Basically, by the time you tube the front and have enough tube junctions and tie-ins to the interior cage and back-half, the body is just going to "float" around the new structure.

A unibody street or drag car won't see near the amount of stress as a Jeepspeed but Rojodiablo does have a good point, tubes without function are, well, useless. Jeepspeed rules are very strict about keeping the unibody structure intact and only allow plating and roll cage tie-in...no tube "chassis" is allowed to be built.

With what you want to do you can essentially build a full tube chassis and then just plate the unibody back in around the tubular frame.

- Paul

[ZTFab]

Your other option would be to fabricate a tubular "K"-member like a Mustang.

You could build your suspension pick-up points off of that and then tie the K-member into some subframe connectors and have the roll cage tie into those.

Not as complicated as a full tube chassis but not as strong either.

- Paul

[onekickkawi]

i will check out the cage when i get home,its a autopower cage and im not sure if i will even use it.. may just start from scratch if im goign to tube everything

[olddad]

Do the "front half" as ZTFab says and hang your sheetmetal on a pivoting tube at the very front. Just build a "cage" out of aluminum to tie the front sheetmetal together (something like the spagetti under a funny car body). If you want further weight reduction later down the line you can add the tubes for sheetmetal support and Dzus it out then.
"Hanging" the front if using the factory sheetmetal really isn't a weight saver over an aluminum caged tilt front. Dipped metal or fiberglass or composite is another story altogether. If you're going to that expense then you definately want to "hang and Dzus" the parts.

[onekickkawi]

i was thinking of using steat tubbing. ..you were saying aluminum? what size? the reason behind tubing is for strength, if i save some weight thats cool but its really to be stronger

[Rojodiablo]

i was thinking of using steat tubbing. ..you were saying aluminum? what size? the reason behind tubing is for strength, if i save some weight thats cool but its really to be stronger
Don't knock the aluminum tubing. At my job in Watsonville, there was a 917 Porche. Flat 8cyl. Tube chassis, all aluminum. MAde in the 70's I believe. Still being raced today. If done right, it could do the job for a street ride well. Not really meant for offroad, but it's really light, and easy enough to work with.

[ZTFab]

Whoa whoa whoa....let's back the fabrication truck up here.

olddad was saying to build the front-half of the chassis out of steel tubing but build a pivoting front clip like a one-piece baja front end on a bug with an aluminum sub-structure for support.

Aluminum chassis' can be strong but take a lot of engineering and tend to be a monocoque design rather than a standard tubular structure.

If you want strong and light, design it correctly and use thin wall 4130 tubing.

I wouldn't recommend using aluminum for a chassis unless you know a lot about engineering.

- Paul

[onekickkawi]

oo got ya alright.. yea i would like to use steal. I was thinking I would just weld tabs on the tube to where the fenders and hood needs to bolt to. After this semester is finished.. (2 weeks) i will start day dreaming and drawing some designs. Then you guys can checkem out and tell me how many mistakes there are lol.

through that process i will discover if i really wanna embark on thejourny or not cause if i tube it... i willbe doing the LS6 swap... and im going to ball park that will cost 14.5k todo.. for materials and for a corvette LS6 motor and tranny

[onekickkawi]

this is the car that got me started on fabrication..

http://www.bryanf.com/510/index.htm

[Rojodiablo]

oo got ya alright.. yea i would like to use steal. I was thinking I would just weld tabs on the tube to where the fenders and hood needs to bolt to. After this semester is finished.. (2 weeks) i will start day dreaming and drawing some designs. Then you guys can checkem out and tell me how many mistakes there are lol.

through that process i will discover if i really wanna embark on thejourny or not cause if i tube it... i willbe doing the LS6 swap... and im going to ball park that will cost 14.5k todo.. for materials and for a corvette LS6 motor and tranny
I agree with ZT, and I wasn't even thinking back to the fact that you already have a steel cage in at least part of the car. If you look up some shops like www.kartek.com they have tube connections, so the front clip can be removed, yet still be stiff and solid when in place. I would not use a hinged design necessarily. It may be more complicated to make it stiff, and to make it work at all. Ther fittings come for a variety of sizes from 1" to 2" .

[olddad]

Whether he goes the route of a tilt, lift-off or individual panel DZUSed on matters not to me, I was just providing another alternative. The link he provided is to a street car so it can be done any number of ways. As my screen name implies, I'm no youngster and prefer the tilt myself for a street application, it's what I grew up with and still like. With fore thought you can fab the front mount to serve as both a tilt and a cradle mount. The only real problem with a tilt version is modifying the bottom section behind the wheelwell for clearance when you lift a tilt. It's really no difficulty at all if you mount the lower half of the fender as you would mount panels on any Comp car or similar design. Not disagreeing with you Rojo, just explaining myself. There are several ways of doing it and they would all be functional, solid and correct.

[stomper4x4]

That one Sweet Datsun.... As for what material to use, What material is the exsisting cage made off?? mild steel or 4130 tubing??? If its mild steel then id stick to mild steel for the front clip......

[onekickkawi]

I would bet that its mild steel im 90% sure it is.. I have to call the company and double check..