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Bent frame suggestions

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Hi guys,

So I have an issue. My car is dog tracking and I’ve redone the suspension. Going off the tape measure multiple times it seems like the rear (shock tower area) of the frame is shifted over/bent about 1/2”. The plan is to have it as a nice street car with a bit of “scoot”. My question is, if taken to a frame shop should it be fine or find a frame to swap? 

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1/4 inch don't seem like much, I'm not sure todays frame machines can pull a full frame like ours or would have the spects to do it. I would get it on an alignment machine and see what that looks like. then maybe if its off then check around frame shops. Just a thought.

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I mean 1/2” ... it became visible when I took off the 3rd gen camaro irocs and put my rallies with 275s. Plus measuring .. the left wheel is tucked inward and the right is right under the wheel well lip. I guess the real question is will the frame be weak that it affects the stability?

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Have you done an alignment to the car? if not I'd get it on an alignment rack and get some real numbers. A slight offset in the rear end is not that abnormal but if its to much it can through the whole car off.

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The bodies on all GM a-body cars are like what you are describing from the factory. Anywhere from 1/4 to 3/4 of an inch difference.  Tire being closer to the right side 1/4 panel wheel opening.   No one knows why. They just are. Most likely your frame is fine. 

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I haven’t don’t an alignment but I should to see where I’m at.

So the rear end  looking like it’s shifted over is normal? I can straight out see the difference.

So say the frame is fine and get an alignment. Next would be to align the body to frame? The body mounts were shot I replaced them. Along with the complete suspension. Just looks like the body is shifted over and it’s bothering me ha..

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Can you maybe post some pictures so we can see what you're dealing with?

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I’ll take some tomorrow after work, and see if I can upload them on here. Still trying to figure how to work this thing. 

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Also take some measurements from the frame to the pinchweld on the body on both sides. At least you would know if the body is straight on the frame. Could be off from doing the body mounts. 

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Frame to the inner wheel well pinch Weld? I know, 3/4” gap on the left and on the right the frame is up against it. So in theory it does seem to be shifted. However when I did the mounts the front half the bolt wholes we’re dead center and the back half shifted to the right. The very back 2 were you can say pinned with the frame. 

I simulated in my head say I center the body to the frame and rear axle I would then have to pry the frame part that’s around the gas tank so I can get the 2 last mount bolts in. 

Another thing is tire side wall on the left is 1/4 closer to the frame than the right. And my Hotchkis trailing arm had to be extended 1/4 longer on the left than right. Hence why I’m in the assumption that the rear of the frame seems to be bent to the right. 

 

I should get an alignment to where I’m at though. My first project car and I’m learning flaws and certain things that are normal about the car, but to me seem off. So it may be fine I guess but just want to be sure.

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Using the picture that Paul posted a couple of days ago in another post as a guide (great timing Paul) , you can take a few cross measurements to get a rough idea if the frame is square. I'd take a few different measurements like below and see what you get. If things are in the way, you can fashion something like a plumb bob from a couple of the holes/points of reference to hang down to get a better measurement. You can pick various spots along the frame to measure, the couple of red lines were just to give an idea. Just a thought..

 

frame.png

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Reading your last post, it does seem that something is not right back there. Using the diagram that jft69z reposted from Paul, you should get some answers. 

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When you installed the body mounts did you tighten them as you replaced them or get them all on and body in place and tighten them all then? Did you replace all of them? Maybe the body is shifted on frame a little bit.

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That diagram pretty much shows everything you need to know about frame measurements.  The dimensions listed may not all be exact, but they're bound to be close. I'd also string some lines down the center, front to back and take measurements toward the side rail reference points. If one side is considerably different than the other, that's where I would start to be concerned. 

I'd start with the "X" measurements to see if it were square first though.

This is all stuff to consider if the body/frame is mated up properly as others have suggested earlier.

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Here’s some shots of how my rear tires sit right now. When I did my body mounts they really shot and disintegrated, but I didn’t tighten the new ones down until everything was is. 

I also did the X measurement and seams really close/almost exact on the cross measurement. 

I’ll get the car alignment done this weekend and go from There. 

F771B09C-3B79-457C-923A-505F0CFE84EC.jpeg

73EDF057-4776-443C-AB48-8873579A1922.jpeg

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All A- bodies are alike to the pictures you posted. Always the right side tire is out just a bit then the left side. I think your frame is fine. I always check frame to pinch weld on left front by fender and left rear inside of rear quarter panel, then opposite side. Question is : what tire size and what rim width are you running? If they are 7" they will look like that with a p255-p275 tire. to get them "tucked"  under, you will need a 8" rim with a 5" offset (measured form back side of rim to mounting surface). Corvette 8" rims are 4.5" and will kick tire out to fender (not good). I run a p275 -60-15 with wheel vintiques 8" and a 5" offset. no issues with fender, actually it sits in about 1/2" each side .post-259-0-93319100-1480263543_thumb.jpg 

Hope this info. helps you.

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The body to frame alignment on these cars is far from precise. You could loosen all the body bushings and move the body around on the frame until the tires have the same spacing within the wheelhouses.

Alingnment pin.jpg

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1 hour ago, Paul Bell said:

The body to frame alignment on these cars is far from precise. You could loosen all the body bushings and move the body around on the frame until the tires have the same spacing within the wheelhouses.

Alingnment pin.jpg

In reality, that circled alignment tool is a precision screwdriver and the arm holding it is a finely machined instrument.

rob

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it has been a while but i recall onnsome cars they had a hole on the frame and one on the body, you could stick a 1/2 or 3/4 bar in there to align body on frame.

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1 hour ago, imr said:

it has been a while but i recall onnsome cars they had a hole on the frame and one on the body, you could stick a 1/2 or 3/4 bar in there to align body on frame.

YES! I don't know how to do it but I think a 1/2" dowel goes here:

frame alignment hole.jpg

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40 minutes ago, Paul Bell said:

YES! I don't know how to do it but I think a 1/2" dowel goes here:

frame alignment hole.jpg

Awesome!! I noticed those holes in my frame and wondered what they were for. Thanks, this helps a lot! I’m definitely gonna be doing some body to frame alignment this weekend.

 

what do you guys suggest/how to approach moving the body? Just loosen all the body mounts and couple jacks?? Or where can I pry over from?

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Don't you need to be careful moving the body? When you move the body do you also loosen the fenders? ....

 

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34 minutes ago, 1970mcss said:

Don't you need to be careful moving the body? When you move the body do you also loosen the fenders? ....

 

Yea, make sure wires and lines are clear. I’m sure moving the body with change the alignment on everything else. Realignment and gapping May be required 

 

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The fenders can stay on, all the lines & wiring can stay in place, you just need to loosen all the body mounts (for the body, not the fenders or radiator support) a bit. I think if it's done carefully, you can shimmy the rear over on the frame to center the rear tires without getting the fenders out of whack. Maybe a fender to door gap will be slightly changed. It shouldn't need a front end (steering) alignment.

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