How far "off" can a chassis be?

[team39763]

Just got my new project back from the frame shop. I had a prebuilt backhalf welded on aswell as a rollbar. Took him about a year to finish it. I didn't notice anything when I picked it up(I was in a hurry, I was tired from the long drive, and a storm had hit). The next day I notice the rollbar is welded in wrong, its clearly crooked and the rear down bars are off center(by 3+ inches) and not completely welded in. That made me wonder about the frame. I talked to the builder and he said my stock frame rails weren't straight so that's why the new frame sits slightly off between the old frame rails. Does that sound right?
Anyway, I'm wondering if I can tune out any small differences in frame straightness or level with the ladder bars or shocks or Anti Roll Bar? Maybe even get a 4 wheel alignment? If I get the rear down bars redone correctly, does it matter that the main hoop is a little closer to the passenger side of the truck(maybe .5")?

[BR3W CITY]

The question I have to ask first is; if the frame rails weren't straight, why didn't the chassis builder either let you know, or proceed to straighten the rails first?
Small differences are pretty normal, but what matters IMO is how those differences translate to the backhalf and its overall "squareness".

If you level and plumb the frame, does it end up square with what he did? (ie was the sum of the old frame and the new frame result in a square frame?)

Now with that being said, 3" + isn't a "little" off square IMO.

[team39763]

I agree, he should have let me know or fixed it. I'll get it up in the air and measure as best I can. I don't understand how it went so wrong. He does this for a living and he's put out some nice rides and now works on some stuff for a well known shop here in Texas. To be honest, I feel like a child who got torn/used clothes for Christmas instead of the shiny new toy I wanted.

[BR3W CITY]

Ok. FWIW, I don't think the .5" off is that big of a problem. Its not ideal, but I think it could be worked out.

Post some pictures of the question areas, I'd like to see exactly how it lines up.

You say he had it for a year? I've seen full chassis done it a shorter period than that. Sadly, I've heard stuff like this from paint/body shops a few times (not from fab/builders as much).

[team39763]

I did some more measuring.
Main hoop is offset 1" to the passenger side.
Down bars(X) are 3" offset to passenger side
Down bars are 2" difference in length

Frame measured out correctly, so I guess I can live with that. I'll let him come and remake the down bars. The main crossmember that I said was slightly off may not actually be off, it just wasn't welded and looks different than the other side. I'll get pics when I get back. He also only made me a 6 point rollbar instead of the 8 that was stated in the contract, so that has to be addressed.

Yep, had it for a whole year. I understand stuff happens, so I get it.

[cableguy0]

This isn't a case of stuff happens and no big deal. If the chassis isn't right nothing that bolts to it can be right. I honestly would have serious issues trusting the guy especially after letting something leave his shop that was so far off. The chassis and especially being straight isn't and aesthetic issue... Its a SAFETY issue. The cage being straight stops it from being weak and shifting from one side to another. There is NO excuse especially having your stuff for a year. I would be looking to get money back and find someone competent to do the work.

[Captainfab]

I have to agree with cableguy0.

[tinydb84]

Anything that you pay for should done to professional standards. It doesnt matter if it is a shop of a friend's garage.

I really don't like "backyard" builders who charge for sub par work. I welded some subframe connectors in my friends Foxbody. He was totally happy with it but the welds were not up to my standard from an ascetic standpoint so I refused to let him pay me.

As for the how far off question, my Z is within 1/16'' from side to side (or 1/32'' off center line) and my back half is within 1/8'' from side to side.

[Marv D]

Like tiny I've done a few that I can't say I'm overly proud of,, but a few small inconsistencies 'MAY' not be detrimental to safety. I mean look at a roadster chassis. The drivers cage is all on the drivers side. So down bars that may not be exactly parallel (although visually FUBAR) might still support the main structure from collapse. Not as though I say he did his job competently,,, but look at the quality of bar fitment and complete welds. Remember there are rules about where the bars go in relation to the driver, pleasing to the eye or not.

This sounds like one person started the install,,, it sat for a year and the truck owner said "where's my truck". , Shop owner said' put that rookie fabricator Jackwad on it, he's not making the shop any money anyways, and get that thing out of here".

All that said, I've seen some pretty twisted up, used up 10 second race cars go straight down the track. I'm not saying this is 'right' , just that if you had a mild steel bar built and not looking for a <10 second chassis cert. 1" here and there may not be such a big deal.

But 3"..... that's a different story.

[team39763]

Honestly, this was meant to run low 9's on motor. I'm not so sure I want to anymore.
As far as the bar fitment, they were hideous if you ask me. I'm gonna just get someone else to redo the down bars and verify square and level then see if I can move on with the build. I'm a little scared to trust another shop now after this.

[team39763]

Here's a few pics.
EDIT: Not sure why my pics are sideways.

[71Dragtruck]

Weld job WOW, that's just sad.

[tinydb84]

Wow....

I wouldn't take it back. I would ask for my money back and find another shop.

[Marv D]

There in no other word for this...

That is simply unacceptable!! Look up Super73's posts on here about the backhalf he had done. Agreed his fabricator was EXCEPTIONAL, but that's the way bars SHOULD fit, and if right there is almost no filler rod needed.

I am sorry for your pain here. Looking at that you were ripped off (even if it was free!)

[cableguy0]

Wow. After seeing pictures I think your chassis builder was trying to kill you. Luckily that would never pass tech inspection but anyone willing to release that from their shop should be put on blast anywhere you can. That is scary. I would demand every dollar back and make him pay the costs of having that junk cut out. Your a way nicer person than I am apparently. If someone gave me that when I paid for a 9 second chassis I would have beat him to a pulp if I didn't instantly get a full refund and enough money to undo that mess. I would be absolutely ashamed if even an exhaust system I did looked like that. Don't take what Im saying as me bashing your stuff but that is straight up dangerous. It isn't even welded......

[mongocanfly]

Man o man..like said before..I'd rip that junk out and start over..and it took a year to do that? Wow.

[PGSigns]

I have done a few cars over the years and this is what I see from the pictures. The main hoop is the wrong shape and to low. It should fit the cab almost exactly. Those X bars will not make it. Do a google search for the NHRA rule book and you can down load it to see what you have to have to run low 9 second passes. It will cover everything from the bars required, the way they have to be mounted along with the size and material. That way you can get this fixed correctly and not have to do it three times. Sucks but the cage all needs to go.
Jimmy

[team39763]

I traded a $6500 truck for the work. I'm gonna talk to the county judge and see where we go from here. We had a typed up and notarized contract. I believe it stated intallation of backhalf, build 8pt rollbar, narrow rear axle, all done within 2.5 months timeframe. I agree, that whole bar mess needs to go. He also spliced in tubing on the bottom of the main hoop (looks like). My goodness I feel like crap. I had big dreams and high goals for this project. Looks like it's gonna take a lot longer. Lesson learned.

[vin63]

As Marv said above, that is unacceptable, not to mention even if it was completely welded, the design still would not pass a chassis cert to run under 10.00 ET (you had mentioned plans to run in the low 9 second ET range, or even quicker). If you have someone else build your cage, or other chassis modifications, make sure that they are doing the work on a chassis jig or table.

[Captainfab]

I agree, the whole mess needs to be cut out. It looks like you got screwed on the narrowed differential also.

[Super73]

Agreed it is not right... But you already know that.

Just an FYI for all saying tubes need to be 100% welded. While not preferred being less than 100%, some tubes can technically be less than 100%... A very good friends 7.50 cert is this way.

[kpeztruck]

Originally Posted by Super73

Agreed it is not right... But you already know that.

Just an FYI for all saying tubes need to be 100% welded. While not preferred being less than 100%, some tubes can technically be less than 100%... A very good friends 7.50 cert is this way.

This is true, but it must have proper gussets and, if I remember correctly, must be welded at least a certain amount around the joint to pass cert.

[indymachinist]

That is terrible quality fab work.

[Super73]

Originally Posted by kpeztruck

This is true, but it must have proper gussets and, if I remember correctly, must be welded at least a certain amount around the joint to pass cert.

Correct.. I can't remember the exact percentage but 90% seems to stick in my head. Don't quote me on that though.

[team39763]

Ran into an older top fuel racer yesterday. He showed me his shop and his work...wow what a difference. He told me to go buy myself a good welder and bring it by his place with a case of beer and he'd give me a few welding lessons and help me fix my truck. I'm hoping to just remove the rollbar and redo it. The plan has always been to send the rear axle to to a rearend shop to be done on a jig as well as re-gear it.
Why wouldn't the design work out well? I thought the x was stronger than straight bars?