Crack in Trans Tunnel

[Okimoto]

So here's the story. I finally finished cleaning the garage and started on the Z again. I was peeling away the jute and sound deadening and saw this crack.

 

The metal overlaps 1/16th of an inch. Is this safe to weld up?

 

Some of you might remember the thread in the past where I had some damage to the frame rails.

http://forums.hybridz.org/showthread.php?t=69331

that's the link to the pictures.

 

here's a shot of the passenger side subframe area, behind the compression rod mount:

 

I stuck a putty knife in there to show the crack.

 

the crack starts from the hole and extends both ways:

 

Here's a shot of the buckled floorpan which may or may not have anything to do with this:

 

Basically the car seemed to have been hit pretty badly in the front passenger side. The pictures show the floorpan being buckled about an inch up, and a shot from below the car shows the subframe connector off by an inch vertically.

 

My question is: How do I proceed? The Driver's side is fine.

 

Right now, I'm not too sure anymore. The logical thing to do would be to scrap #1661 and buy a chevelle. But the ego thing kicks in. like how some guys dont like asking for directions, i dont want to give up on this car. Giving up on this car would be like saying I don't have the knowledge or availability to this knowledge (you guys) to fix this car.

 

I've done some searches and I haven't seen a thread where there seems to be stress cracks in the trans tunnel. I've seen some threads but most of the threads dont have working pictures anymore either.

 

So, what do you guys think? Lost cause? can this be spot welded without knowing the cause? Should i chop off the floorpan?

[BWRex]

If possible,I would start with taking some precise measurements,and making certain your frame isn't out of alignment.(The last thing you want is your Z doglegging down the road!)Most good body shops have frame racks that they use for fixing,aligning,etc. damaged frames.Yours took a pretty hard hit to take that kind of damage,so IMO,that's where I would start.I'd then add some 'Pete Paraska' style subframe connectors,straighten all of your floor pan steel,etc.the best you can,and weld them to the subframe connectors.A bit of work,the 'right' way to do it(depending on who you ask)with the strength added and the piece of mind, you can't lose.

[A. G. Olphart]

 

My question is: How do I proceed? The Driver's side is fine.

 

So' date=' what do you guys think? Lost cause? can this be spot welded without knowing the cause? Should i chop off the floorpan?[/quote']

 

 

There doesn't appear to be much (if any) rust problem, so the car is far from a lost cause.

If you haven't bought that high quality MIG welder yet, you still need to get one. (I'd say the only other option would be to take the car to JohnC at Betamotorsports and say "Go for it"). You and the new welder will not do as nice a job as John, but when you finish, the car should be structurally sound, and you will have acquired a new set of skills.

 

I've no idea why the tunnel would flex enough to break there... a 700 pound passenger??? Whatever the cause, just welding up the crack in the work hardened metal will not (in my insufficiently humble opinion) constitute an adequate repair. You might ask John how best to reinforce it

 

You will also need to make sure the suspension pick up points are properly aligned, the doors fit and latch, and then give the car some frame rails.

 

Your hobby just got more interesting.

 

 

.

[Okimoto]

It's weird. the doors fit and closed fine. the panels were a bit out of alignment but workable, and there was obviously an earlier repair attempt. The crack might have been recent (after I got the car), or maybe early, but I don't know. The trans tunnel is weird in a way that the rear transmission mount was thru-bolted using two different kinds of bolts. The bolt holes on the inside were drilled out to provide this. I believe it's because the transmission would not bolt in straight after the accident. I found this out after I saw the holes in the trans tunnel to the transmission mount.

 

The front frame rail seems to be welded on the outside and a small reinforcement welded on the inside.

 

I've read a little bit and am considering a millermatic 175 from a local welding supply store with the 'house special' co2/ar mix.

 

How do you guys take precise measurements? I was thinking about tying a string to the front strut tower and going criss-cross. Should I take the tires off the car? should the car be off the ground for this? How about tolerance? 1/4 inch? I used to be able to tell a 64th of an inch on a blueprint, but this is a really old car. I have the chassis dimensions from this site and am getting the strut to strut tower measurements by using pythagorean theory.

[johnc]

So, what do you guys think? Lost cause?

 

IMHO, this chassis is junk. I would not use it as the starting point to build a car for myself or a customer. But, the decision is yours.

 

If you decide not to build it, why don't you use it to learn how to weld? Also, carefully remove any good body panels and sell them on eBay. Right now good rocker panels and rear 1/4 panels are scarce.

[A. G. Olphart]

OUCH!

John doesn't pull any punches.

 

If finding a straight, rust free car is an option, it is certainly the simplest concept. Saves all the sweating over getting things aligned in 3 dimensions (and all the time/work involved). Your misaligned panels would seem to indicate additional tweaks in the structure, which lends more weight to John's already heavy expert opinion.

 

If you want to learn to weld, and expect to build things throughout your life, get the welder and have fun. The Miller line is good stuff.

For thin metal like a Z car, the .035 wire that will likely come with that machine is (IMO) too heavy. (Try a search on welders for other opinions). I have an old 110V Miller running .023 wire, and it does fine for my household projects.

 

It comes down to what you want from your hobby car. With the twists and kinks it has, it won't become a show car. If you want to learn welding/ fabrication and are looking for a fun ride, you could do worse. (You do grasp the basic geometry involved, so success is possible). Will you enjoy spending LARGE amounts of time in the shop?

 

As to precise measurements: Some of the big boys have huge flat steel plates they measure from and weld jigs onto; not an option for most Z freaks. I think a person could use a laser level and redirod/allthread hung from the bottom of the car to work with twists from the horizontal. (Car would have to be off the floor). For just plain bodywork, your 1/4" might be Ok for a street car, but suspension locators need to be just as close to dead nuts as you can get them.

 

I ordinarily don't like roll cages in street cars (care to bounce your skull off a steel baseball bat?) but combined with frame rails it would give your vehicle some structural integrity. Then the body panels would be mostly along for the ride.

 

Guess that's your book for the evening.

 

 

.

[katman]

I'm with John. There's lots wrong with this car that you proly don't even see yet.

[BWRex]

I suppose it really boils down to how attached you are to your Z.

 

ANYTHING can be fixed,it just depends on the level of dedication you have as an individual.I agree with the guys on this thread,the shell is not the greatest,the prior craftmanship is a little shoddy,and there are Z shells out there that may be a little rusty,but haven't been in a frame tweaking wreck.So I'm with them on that,but on the other hand,with hard work,careful planning,triple checking measurements,and the ability to tackle such a big project,(just look at Mull's video collection)the gratification of building a car literally from the ground up,IMO would outweigh tenfold.

 

Plus, I'd rather see someone bringing a Z back from the dead,than a junkyard car crusher squeezing the life out of it.................

[boodlefoof]

could always cut out the entire frame structure and build a complete spaceframe chassis to replace it, then graft the body onto that. That's what I'm doing.