Welding on an EFI Cars and sub frame connector ground clearance

[7991LXnSHO]

When welding in general, and installing sub frame connectors specifically, what precautions are needed to protect the car’s computer? Is unplugging the positive terminal really enough?

What subframe connectors give the best ground clearance without cutting and going through the floor? I do want seat mount cross bars, but otherwise I am open to suggestions and do not want more lowered car pavement scrapes than needed. Thanks!

 

[Opposedodie]

I have wielded on my car and that was the only thing that I have done, Buy taking the + Battery terminal off you are isolating the cars electrical system..

 

[7991LXnSHO]

STATIC not and issue?

So STATIC is not and issue? It must be tougher than my desktop computer.

On a side note, I saw a Camaro go up in flames this week due to static. He was pumping gas, got a phone call, got static getting in and out of the car and up it went. Nice kid even if you hate Camaros.

I still would like opinions on subframe connectors that drag the least.

 

[rd]

Through the floor subframe connectors will drag the least, followed by 1 x2 or similar square tube. I have those on my 82.

 

[Opposedodie]

There is always a risk of Fire when wielding... I have seen people take out there gas tank and go to extremes to prevent a fire when wielding on there cars... But the electrical system is isolated when you unhook your battery...

 

[LarsD]

The chassis builder that installed my MM sub frames on my 91 and my Cobra didn't disconnect the battery. I think as long as you place the ground clamp close to your welding point, the current won't seek a path through the computer and it will be fine. That being said, I disconnected my battery when I had to patch a hole in my headers on the Cobra.

 

[RangerJoe]

Yeah, definetly disconnect battery. I have full length steeda subframe connectors with the seat supports. They do hang a little low in places. My car is dropped 1 3/4" in front and 1 1/2" in rear. The only dragging I have ever had has been the front air dam and my x-pipe. The time my x-pipe drug I had the front end lowered 2", I raised it up 1/4" and have had no more problems. It was only dragging when I entered my garage because my drive way is so steep.

Talk to who ever does your welding, but you may want to remove your carpet before welding on your car, or at least put a wet towel over the carpet that covers the area you are welding.

 

[reldla1996]

I've never disconnected my battery before the numerous times my car has been welded on, and not had any issues with the computer, but I sure laughed at Ranger Joe's comment on the carpet - mine has a couple burn holes where the welder burned through the floor pan and caught it on fire..... Details!

 

[scottda]

subframe connectors

To be safest disconnect the battery and electronics such as processor and ignition box

 

[dgollem]

I have MM sub frames on a lowered car (the black one) and no scraping even over speed bumps.

 

[Shakerhood]

I always disconnect the battery when welding, i also layed a wet towel and a bag of ice on the carpet before welding my SFCs in.

 

[wizwrath]

Run the Maximum frame connectors...if you are low enough or go over something that steep you would want the frame connectors to scrape first....you wouldnt want somethign else to scrape, like the exhaust system, because that creates a lot more problems like bending or braking things (exhaust hits can and will create problems else where).
when welding, we at least disconnect the battery and ignition boxes etc. and remove the ECU (with the battery disconnected you still can short out the ECU, etc.), and we at least lift up the carpet and place a 2X4 piece of wood between the carpet and floor pan. and the welding should be done in short stitches in different areas anyways.

 

[vertvert]

I have observed many exhaust shops welding on every vehicle that enters the shop not have anything at all disconnected when welding exhaust. Electrically speaking the exhaust has the same potential to ground as your subframe connectors. Not one of these thousands of vehicles have had electrical problems post welding.

On the other hand I had a welder on an industrial 3 megawatt engine welding some piping above the engine while grounded to the iron skid. Anyone want to guess what happened?

 

[7991LXnSHO]

Welding and Carpet

Thanks for the carpet warnings. I do not remember how I did not burn up the 79's carpet at this point. That would have been the wrong kind of exciting!

 

[1bbcd5]

Thanks for this post guys I was going through the same thing