DSE Subframe Connector Problem

[ItDoRun]

Someone please answer this one for me. Below are some pictures of when I first fit the sfc's in the car and tacked them in place and then pictures from tonight of when I tried to fit the subframe back under the car to get it on the ground. How in the world did the sfc's move that much? They were fit perfectly and then tack welded in about 8-10 spots before final welding. When I welded them, I took my time and made 1/2"-1" stitch welds moving around from connector to connector and side to side to keep the heat down.

The seat pan brackets were not in the car at the time I installed the connectors and I consulted with DSE about the floor flexing because of that. They assured me that I would be okay. I was cautious about the floor flexing because of this but it appeared to be fine. It would have had to dent the floor noticeably if the connectors are this far off.

Any suggestions on how this could have happened?


Before:
http://carphotos.cardomain.com/ride_images/2/4568/2281/23918640244_large.jpg

http://carphotos.cardomain.com/ride_images/2/4568/2281/23918640251_large.jpg

After:
http://carphotos.cardomain.com/ride_images/2/4568/2281/23918640327_large.jpg

http://carphotos.cardomain.com/ride_images/2/4568/2281/23918640326_large.jpg

[JamesJ]

I am sure you can tell and would not have asked but is the the gap between the subframe connectors and the floor gotten smaller, just making sure that is the part that moved.

[ItDoRun]

I didn't measure it before I welded, but yes that seems to be the problem.

[Vegas69]

Are you sure you didn't mix up the subframe bushings?

[ItDoRun]

Are you sure you didn't mix up the subframe bushings?

I'm positive. Unless there's a difference between the firewall bushing and the rear subframe mount bushing.

[Vegas69]

I'm not sure, it would have to be noticable to the eye to be off that far.

[Denvervet]

Mine did the same thing to some degree.I purposely didn't weld the end connector piece onto the SFC until I had the sub permanently in place .....after all body work and tweaking was done. Another thought maybe the way you have it supported.....try supporting at the axles/wheels instead of the rockers/frame and maybe it will sag a bit in the middle. just a thought

[98ssnova]

Mine did the same thing to some degree.I purposely didn't weld the end connector piece onto the SFC until I had the sub permanently in place .....after all body work and tweaking was done. Another thought maybe the way you have it supported.....try supporting at the axles/wheels instead of the rockers/frame and maybe it will sag a bit in the middle. just a thought

I was gonna say the same thing shouldnt you have had it on the wheels for this and also did you have the subframe aligned when you tacked them in

[redfire69]

I would try suspending/supporting the body and frame in the same fashion as you did in the first pics to see if that changes anything, but the SFCs look closer to the floor in the second pics to me too.

[DOOM]

At first glance, they look upside down.

You know as crazy as that sounds I was thinking the same thing but ther not ... I'll be watching this one..

[Bow Tie 67]

I hope I'm wrong, but I believe the movement came from incorrect support while tacking them in. To compound it, if you changed the support or removed the subframe and put in the seat supports that could have created more movement.

The fix, not sure until we find out more info on how she was supported during each process of adding more components.

Are the second set of pics taken with the front support at the subframe or suspension?

[ItDoRun]

The body supports have not changed from picture to picture. The body was supported at the front and rear of the frame rails on jackstands and has not moved. The subframe was placed under the car using the DSE body bushings, aligned, and tightened. I then supported the front of the subframe with a hydraulic jack to take any potential load or flexing out of the equation since the weight of the subframe I thought could flex the floor without the seat pan brackets in. i didn't notice any flexing during the process.

The only thing I can think is that the floor did flex, BUT here's the thing. After I tacked the connectors in place, I removed the subframe. If the floor had flexed with the frame in place wouldn't removing the frame allow it relax back to its natural position? If so, wouldn't the connectors relax with the floor.

I would expect to see a noticeable crease in floor if it truly moved this much.

They'll work like they are, but they're not right. Why is the major question right now.

[War]

Looks to me that the floor flexed with the heat. I dont know what size welder your using or how you cooled the weld while you were welding. I would just cut the weld loose, tack the SFC to the subframe, the weld it up.

[ItDoRun]

Looks to me that the floor flexed with the heat. I dont know what size welder your using or how you cooled the weld while you were welding. I would just cut the weld loose, tack the SFC to the subframe, the weld it up.

I'm using a SP-100T Lincoln. I can't see where the heat did this because both sides moved identical, but at this point anything is possible. Plus, I used small stitch welds and moved around enough allowing the welds to cool.

[ItDoRun]

I talked to Mark at DSE and he pulled Paul in for the discussion. It appears to Paul that the connectors drew upwards from the heat. It doesn't appear to be a problem in terms of function, however he suggested I weld the underside now to help draw it back.

The problem I see is that the connectors are fully welded on the inside of the car and I would think that I need to cut the welds loose to help relieve it so that it would move in the opposite direction.

Maybe I can use something to put tension on it and pull it as it's being welded?????

Any other thoughts?

I see where I messed up now. It's a stupid mistake on my part. I guess i rushed it and didn't stop to think about it drawing as much as it did while welding. What I should have done was welded the some on the top and some on the bottom to minimize the draw. Oh well, lesson learned.

[DRJDVM's '69]

Personally I think I would just cut the SFC free with a cutoff wheel or air body saw and line them up again and re-weld.... the offset heat thing can get really tricky if you dont know what youre doing....it could even make it worse,or just make a bigger weld that you may end up having to cut free and reposition the pieces anyway.

Heat in sheetmetal can move thing alot....... lesson learned....fix it and move on.

[v8s only]

I got the speed tech body mount bushings, and there is a difference between the firewall one and the rear one. The rear is slightly smaller make sure you didn't mix them up before you welded the frame connectors. Hope this helps!

[lil427z]

what you have done is 100% right. go to dse site and take a look at james 69 camaro. hope this helps.
rick k

[ItDoRun]

I should have installed the seat braces first. That would have given the floor pan the additional support it needed during welding.

I'll get it fixed. It's just more time involved and yet another lesson learned.