Stitch welding mk3 chassis?

1986.5supra_kid

Rice? No its Corn (E85)
Stitch welding mk3 chassis

I have a hardtop mk3 and I'm entertaining the idea of strengthing the chassis by stitch welding the seams of the panels on the bottom,shock towers,and the rear subframe. Has there been anyone that has done it or have notes on there research?
 

IJ.

Grumpy Old Man
Mar 30, 2005
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Scooter7M;1941405 said:
Im interested in this as well. If no one chimes in, I say take a crack at it. Its not like there could really be any negative effects.
Most of the structural parts of a Mk3 are pressed from thin gauge Hi Tensile Steel so YES there can be many negative effects.... :nono:

Not to mention 25 years of corrosion and seam sealer in the way...
 

yhatzee89

Joe Yantz
Aug 31, 2012
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Like most things, I imagine if done incorrectly, there could be a lot negative effects. But if done correctly is it worth it?
I read a few threads on other forums about it
http://www.supraforums.com/forum/showthread.php?614581-Spot-stitch-seam-welding-chassis..
http://www.dirtyimpreza.com/forums/showthread.php?t=9637
One thing that was mentioned was ratcheting the car down by the corners to pull the cars suspension to maxed out before you start welding. Another thing mentioned was bouncing from one end of the seam your working on to the other to prevent warping the panel.
And IJ aren't you supposed to clean an area before you weld it? Wouldn't a wire wheel work pretty well for that?
 

80083r

New Member
If you clean it well enough, yes, you can put a clean weld on it - but the point I think IJ was trying to make is that the steel is heat treated or tempered to a certain point.
Heating it up and cooling it down will change that, and put stresses in (or take them out, or move them) even if you don't see any warping, you could end up with a weakened chassis and not know it.

Technically possible? yes
Advisable? I wouldn't do it, but YMMV
 

Supracentral

Active Member
Mar 30, 2005
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Suprapowaz!(2);1941470 said:
Has anybody ever thought about doing some kind of subframe connector. Is it possible with our cars?

not-this-shit-again.jpg
 

#04

New Member
Sep 7, 2009
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I did it
Inside/out - top/bottom

On a strippd bare targa

Took weeks

Maybe months

Then resprayed everything in epoxy

Not worth it unless your stripping the chassis for a resto. IMHO


I. Left front/rear areas between bumpers/strut towers alone for crumple zones
 

Supracentral

Active Member
Mar 30, 2005
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yhatzee89;1941487 said:
You have a whole library full of these pics dontcha? Lol

You wouldn't believe how many... :D

Suprapowaz!(2);1941526 said:
I take it I said something dumb? Can it not be done, or is it a bad idea for our cars? Honestly I've never seen this topic discussed before.

No, there was just an epic fail of a thread on this topic a couple of years ago... Guy did some strange shit to the underside of his car. I'll see if I can find it.
 

1986.5supra_kid

Rice? No its Corn (E85)
The idea came to mind when at road atlanta and they stitch welded there ae86 chassis, thought that the heavy supra could use some stiffing up if i plan on some weekend drag racing and road racing. its bone stock. besides the engine and drivetrain. figured the pre 89 rear sub will need some support too.