Not sure where else to post, frame/cage question

[aonghus]

Well I've been tearin down the '68, I've known the rear frame rails were pretty messed up for a while. Figured I'd figure out what to do when I got to a point where I could deal with it.

Well I'm there now and have no clue. I plan on caging the car, but may not do it immediately. I don't trust the way these look. (mono leafs, slappers and an abusive previous owner, collision damage even?)

https://static1.pt-content.com/images/noimg.gif

driver side, side view

https://static1.pt-content.com/images/noimg.gif

driver side, under body view


I plan on taking the car to get it dipped, and possibly farming the frame rail replacement out. What do you guys think I should do? Does the car need to be checked for straightness?

If I tied in a cage, could the rails just be TIG'ed up or are they compromised?

Thanks a bunch guys, input always appreciated

[speedster]

If you don't want to go through the time and expense of replacing the rails, you can box them. Very strong. Personally, I would have the frame straightened, or at a minimum, when you get it all together, have it 4 wheel aligned. Just my .02 cents.

[aonghus]

What kind of business should I search for to 'straighten' things out?

[vanzuuk1]

From what I have read , the correct way to align the frame is to drop a plumb line from each suspension pivot point on the frame and body.Mark the points on a level floor. Measure all these points to make sure the suspension will be square left to right and front and back then weld the frame connecters so it stays square. The point is to align it all so the wheels are in a cube and the pickup points are level with each other. Once that is done you can do the cage and the repairs to keep it that way, or close to it.

[wendell]

Too add to what Dirk said, your camaro assembly manual (you do have a manual right?) will give you the factory reference holes and their dimensions. If it's square, e.g. everything with in 1/16" just weld it up with some fish plates. There's not much going on as far as forces after the front spring eye. Super clean car by the way. Have fun with it.

[aonghus]

Too add to what Dirk said, your camaro assembly manual (you do have a manual right?) will give you the factory reference holes and their dimensions. If it's square, e.g. everything with in 1/16" just weld it up with some fish plates. There's not much going on as far as forces after the front spring eye. Super clean car by the way. Have fun with it.

I do have a factory assembly mannual, brain fart, checkin it when I get home...

By fish plates you mean reinforcing the cracked area with some plate on the outside of the rails? I planned on mini-tubbing the car, dontk now if that will interfere or not. Should I just bash the bent out sections where the crack is, or shave themm off then reinforce over that? (God I feel like a newb)

I'm going ditching leaf springs, going to convert to an alternative means of locating the rear. From my understanding a coil-over crossmember would be the only thing in the general area of the cracks that would be under any kind of load.

btw, I beleive that isthe first compliment I've ever heard about my car LOL thanks a lot wendell.

[wendell]

you're right about fish plates. I'm a HUGE fan of the leaf spring so I hope you reconsider. With the exception of Mean69's camaro I haven't seen many link(2,3 or 4link) cars go fast on a track. That said, if you're going that route you will want to pay attention to how your cross member ties into the injured area of the frame rail. If you're going through the trouble of a link suspension you may want to replace the frame rail, if for no other reason than estetics(i spell like a four year old but can do math at a high school level).

Lastly, if you're bent on a link rear, get in touch with Mean69(Mark). It's the only system I would even consider and Mark's a certified Good Guy. Give'em hell.

[Jim68nC]

I also have similiar damage to my frame rails although not as bad. I have been considering boxing over the frame rails from this area back to the rear spring perches. Is this fairly common? I do not recall seeing it on my previous '68 although it may have.

[vanzuuk1]

Hey Wendell, I figured its better to measure from the suspension mounting points because thats whats critical, and it might be off from the factory points. It may be overboard but its the last chance to square it all up before cage and connecters.

The guy who is going to do my cage and connecters is near lime rock, I will let you know when I am ready to start. You can stop by if its not too far.

Also, when will you be at lrp, soon?

[Rick Dorion]

Dirk, who are you using? I want to have some more work done myself.

[wendell]

Dirk,
I agree about squaring the suspension points but if I remember correctly themanual gives some dimensions for locating holes in the frame rails. LRP is a good three hours from me. We'll deffinately be there for laborday and might be there for Memorial day. There's a bunch of killer weekends this summer because it's being billed as the 40th aniversary of TA. The 80# is going to be POPPING!

Good to hear you're moving forward on your car. I spend a few hours cleaning up my door shells tonight. Slow and steady...

[Mean 69]

Good advise from the guys. The fracture wouldn't alarm me too much, if the car is going to be driven (and from the sounds of cage install.... it is) then reinforcing over the area will be fine. Obviously, you'll want to inspect the rest of the points on the car too. I personally haven't seen a rail crack like that, when it's all said and done, this is actually a pretty stout portion of the car, the quarters, trunk floor, fenderwells, etc are all integrated and together make a strong system. Drag race launching? That'd be my guess? Was there any evidence of strain on the body, like funky gaps on the trunk or door areas? If there's nothing else that would really compell you, repairing this rail rather than replacing is fine.

Checking a frame with some good reference points like Wendell suggested is really easy, all you need is a level floor, some masking tape, carpenter's square, good tape measure, and a plumb bob or two. I encourage everyone to do this type of work themselves, it's really educational, and every time you do it, you learn something new. Keep in mind that the factory tolerances are not super duper tight, especially on the subframes up front (we measured some "interesting" numbers on the unit that was removed from my 70 project car), so if something is close, but not spot on, don't freak (yet). That certainly does look like a solid car, you're fortunate!

Lastly, if you are going to run a cage, by all means, use a shop that understands what the cage is supposed to do, I think there is a really good shop in the Bay area, there's a great one down here too. The cage isn't just a bunch of tubes put together that magically transforms the car, it requires a lot of thought regarding the load paths, triangulation, etc, you're just not going to get that with a catalog bought drag race do it yourself kit, independent of the lower quality tubing they typically use. I'd guess that 90% of the cages that I have seen have issues, ranging from "duh, why'd they do that," to serious.

'course, I'm a little biased, but if you do think about a new rear suspension, give us a shout, we have a very cool solution (we'll have an equally cool and functional front solution in the near future too). If you want to run leafs, then trust me, just do what Wendell says, he is the real deal and knows exactly what he is talking about. Above all, have a blast with the car, this hobby is the best, hands down.

Mark

[vanzuuk1]

Wendell, send me your info again when you get a chance.

When I squared up my car I figured its better to drop a line from the holes where the control arms and leaf springs pivot, since the suspension is really what i am checking, not the frame rails. Am I right?

[TLWiltman]

Wendell, send me your info again when you get a chance.

When I squared up my car I figured its better to drop a line from the holes where the control arms and leaf springs pivot, since the suspension is really what i am checking, not the frame rails. Am I right?
A quote from Larry McReynolds that should answer this question.
"Racers often place too much importance on the frame rails... Even if the frame rails are bent like a banana, it's OK, as long as the suspension pickup points are still where they're supposed to be"

[vanzuuk1]

So , just this once, I was right? Wow!

[TC Design]

I wouldn't be too worried about the crack, just weld it up and put a re-enforcement plate in that area. The top of the cage will have most of the forces going through it if properly built and tied into the chassis.

-Tony Colicchio
www.tcdesignfab.com (http://www.tcdesignfab.com)

[aonghus]

Here's a question for ya fellas: What if I were to not install a cage?

(I saw the craziest accident of my life 2 weeks ago 30 feet in front of me, and 3 blocks from my house, I'm cagin'. But what if?)

and thanks a million for all the responses :3gears:

[vanzuuk1]

This is not an answer, but a few observations.

A poorly planned cage can kill You if a broken bar impales you or you hit your unhelmeted head on one of the bars.

You would not believe where your head can end up in an accident, (still attached to your head) pretty much any where in and out of the car.

You cant anticipate what type of crash you will have.

A seat properly attached is essential, the belts should be also attached securely.You can find guidelines for this on most race club websites.

There are people who swear a cage is more dangerous for a street car (no helmet) and people who insist you need a cage.

I like when the seats have "ears" around your head to encase your head,combined with four points and a cage. I am still kind of thinking over the rest of the details.

I think the minimum should be a good seat (up to the shoulders with a headrest) and good three point belts.

Read the "breaks my heart" thread for a lot of good info.

[aonghus]

I have Corbeau TRS Seats vanzuuk. I picked them for the exact reasons you mentioned... keep me noggin in the middle of the seat, or at least from bashing a window. 4 point harness as well...

all in all though, I am 6'4", if I were to get into a serious enough accident, I'm done for. These cars weren't built for guys my size.

I don't expect a cage to save my life in the event of any type of accident, but I would hope it would make the car more structurally sound in the event of one...

[vanzuuk1]

Aonghus, I am six feet even, and with the summit seats my helmet is close to the roof,you must be close without the helmet.??

Do you have a photo of the seats in the car?

[aonghus]

https://static1.pt-content.com/images/noimg.gif

Can't see the roof to seat clerance to well there, plus that is a bit of an old picture. Car is in pieces right now...

If I put the seat in a fully upright position, and I sit up straight, my head must be completley tilted from side to side, (without headliner) in order to sit in the seat... (Corbeau's brackets, which I plan on modifying raise the seat aprox 1" off the floor pan/mounting area)

The only way I fit in the car is if I pull my seat forward, and tilt the seat back, so my knees make it around the column, and my head clears the roof. It's tight, its probobly not 'safe' but I can't make myself smaller (at least height wise LOL)