Subframe weld on's but bolted
 

Waiting for my Founders Subframe Connectors to arrive and was thinking of instead of welding them in place I might bolt them instead. As I live in Australia parts cost a fortune to post and at present the exchange rate is low. Has anyone tried doing this with Founders SFC's. Guess I'm worried at the thought of welding them and then finding I have fried some electronic parts like the PCM or Stereo etc.
I know if the battery earth is disconnected I should be ok but over here there is not much support for these cars and I just think this would be a bit safer but not as ridged as welded.

Re: Subframe weld on's but bolted
 

Don’t know the specifics of the Founders parts. But I remember a magazine article from many years ago that had photos of “bolt in” SFC’s in a 4th Gen F-Body, and the bolts had torn the subframe metal, rendering the SFC’s useless.

If you are worried about the electronics, they are relatively easy to disconnect. But I have a fully welded-in roll bar assembly with integrated SFC's, and have had extensive welding on the exhaust system, and welding on rear suspension components, by three different (but knowledgeable) shops, and all my electronics, including the very expensive MoTeC ECU, never suffered any damage.

Re: Subframe weld on's but bolted
 

Graeme Redman,

I have no experience with auto welding, but I share your concern. I have long experience with electronics, but it was all indoors. Can the welding job be done by gas, or must it be done by electricity?

If the job is done by gas, it would be a good idea to weld a short section of the perimeter (~5 to 10 cm) on one side, then jump to the other side of the sheet, then to each of the ends, and continue on in this manner until the entire job is complete. Welding in these short segments should minimize any heat warping of the metal.

If the answer is electric, I would make a few suggestions. The car battery can be disconnected. The ground lead for the welder can be kept as close as possible to the actual welding, not just attached anywhere. All of the fuses and relays can be pulled out (but make good notes, label the relays, and take close clear pictures of the fuse boxes, before you start). Your car may have inline fuses, or fusible links, that can be disconnected. Any fuse can pass enough surge current to damage electronics. A wiring diagram may show you important connectors that can be dis-connected, before welding begins.

I do not know if removing all power to the car might erase the settings in certain component memories, but since power is lost whenever you change batteries, this idea may not be a concern; you may have some time limit to get power restored, though. More experienced local people would need to address that issue for you; here in the USA, we may or may not have cars equipped like your car.

Take a cautious approach, get good local advice, and take no shortcuts on the job. HTH.

Re: Subframe weld on's but bolted
 

Thanks that's very encouraging,

Re: Subframe weld on's but bolted
 

Done will take better pictures once on ramps and a report on handling.







https://cimg2.ibsrv.net/gimg/www.cam...3267491141.jpg
weld is on side but hard to take a photo
https://cimg3.ibsrv.net/gimg/www.cam...60a4220ccd.jpg
Boxed area was not in full contact to body but new pic shows weld at other end
https://cimg4.ibsrv.net/gimg/www.cam...52f475264b.jpg
Weld is on both sides of hole

Re: Subframe weld on's but bolted
 

https://cimg5.ibsrv.net/gimg/www.cam...3ac331c6a6.jpg
Repainted mechanics first effort looking much better
https://cimg9.ibsrv.net/gimg/www.cam...cd428c53b4.jpg
These Founders Subframe Connectors do sit nice.
https://cimg1.ibsrv.net/gimg/www.cam...7553a01793.jpg
Other side of car installation.
Have better shots of the installation, not overly happy with my welders efforts guess I will have to check them every now and then. But it seems to be strong at the moment and yes most of my rattles are gone. So that's a plus.