Suggestion for welding hi-flow cats?

[Achilles99]

OK, I'm finally getting around to putting hi-flos on my 2001. On previous Vipers, I either band clamped them, or had them welded at a reputable shop in Atlanta.

Now that I'm in Durham, NC, I don't trust anyone yet How would you guys suggest getting the hiflows welded? I was thinking of removing the flex pipe, stock cat, and muffler (I have the Corsa exhaust) together as one unit. Then, I'd bring those pieces in to have stock cats removed and hiflows welded (including cutting the 2.5" piece off the front of the Corsa muffler, which was made to fit with the 2.5" stock cat). Do you think it would be too hard to get the pieces to line up again?

 

[EA6BPilot]

Achilles99,

I am getting ready to do the same thing myself. The only thing I can think of is to cut out the old cats, tack weld the new pieces in place, and then remove to finish the job. I am fortunate as I have access to a garage/welder on MCAS Cherry Point to do so. Otherwise, I think that if you clamp everything extra tight and are careful when removing, I don't see why everything wouldn't line up. Of course, I may be wrong......

Good luck! Be sure to post how well it went!

Frank

 

[TorQ Junkie]

Lining up the pipe after welding could be a headache. If you are willing to take off the sills and remove parts on your own, you would minimze damage and down time by setting everything up at home and letting a shop tack weld things in situ. That way you can wait on the job and make sure they don't go for a "test drive". Shops like Midas could handle that. The only potential problem would be fitment of the sills after it is all done. Roe ovals come to mind. Bullet type should be no problem.
I live in a small town and do not relish the thought of having to use anyone either, so I learned how to Mig weld and did a couple exhaust mods on the Viper myself. I put flanges on the separate pieces so that I could replace cats with straight pipe.
While driving around town without sills, I picked up a rock chip on the driver side door. Not sure if it would have been blocked by the sills if they were there, but be careful if you do.

 

[Achilles99]

Thanks for the suggestions...

Has anyone ever tried gutting out the stock cats? I thought this might be a good opportunity to experiment with that... if I don't like it, I'd just go forward with the hiflow install.

My only concern is wanting to go to straight pipes if I don't like the hi-flows. I like the flange idea...

TorQ-where did you get the necessary flanges? I might have to bite the bullet and get a welder... my brother is taking welding classes as part of his auto engineering degree, so maybe this would be a good chance for him to experiment

 

[Qualitywires.com]

I just did mine.

I took out the flex pipe and replaced it with a 3 " staight pipe. welded on my **** for the wide band o2.

I've got 90 degree bends if you want to buy some from me cheap....they are mandrel bent...or got to midas and have them bend it for you.

I welded up my own system. I would recommend if you weld to use argon mix and not the flux wire..if you do use the flux wire...use a blow torch to heat the metal up real good...you will get a better weld.

I tack welded everything in place and then took it apart and welded it. I used flanges so I could take it apart also without having to cut it. It's really not that big of a deal is if you have the right stuff to do it with.

 

[joe117]

Put the system in place with the sills off.
Weld as much of it as you can reach with the system in place.

Remove it to finish the welding.

I don't see any point in just tacking it in place before removal.

Just don't set the car on fire and don't get welding spatter on the paint.

If your welder has decent power, you shouldn't have to heat the area with a torch.

Gas shielded is the way to go. The flux core wire makes for a messy job.

 

[Johann]

Since most cats are stainless, are you guys using a regular mild steel MIG wire to weld both the stainless and mild steel?

 

[jcaspar1]

I just cut off my cats and put on the Corsa and high flow cats. Then had Midas guy weld them on while on the car. If they put it on a lift at the right height they can weld all the way around .