just a simple question for all you professional welders. im getting some mandrel bends together to get my own downpipe custom built. the pieces i will be using are "aluminized steel" which is pretty much aluminum, right? so my question is, is it possible to weld the aluminum downpipe to my stock exhaust system? i cant afford the apex n1 exhaust system just yet, so i hope the stock exhaust will do for a month or so. I would like to bolt the pipe directly to the cat, but i dont know where to find aluminum flanges to weld to the downpipe. someone please give me some answers or solutions to my budget problems. any suggestions are appreciated. thanks.

 

no it is not aluminum , it is aluminized steel just so i will not rust, you can weld it and you will use just normal steel flanges, i would ditch cat for shure you will gain power, and make the install more simpile,

 

Make sure to grind off the "aluminized" part off the surface before welding. I don't think it's safe to inhale the fumes from it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Finest &raquo;</TD></TR><TR><TD CLASS="quote">Make sure to grind off the "aluminized" part off the surface before welding. I don't think it's safe to inhale the fumes from it. </TD></TR></TABLE>

i think your right that stuff smells funny, lol

 

Yes it is harmfull, but we're young right? Aluminized steel is a chemical process you can't grind it all off. Most people just weld it but "your supposed to use a venting system" But who has money for that ish.... ??? I wouldn't worry about it too much its not like you do it for a living right?

 

Aluminized piping SUCKS to weld. First you have to try and grind off all of the coating... which never happens. Then when you think you have removed it all, good luck getting to the insided of the piping to remove the interior coating. The welds do not look as nice as a SS weld in my opinion and the interior welds look like garbage in some instances when the piping has an aluminized inside piping.

 

I don't see why you can't grind it all off...it's nothing different from galvanized coating. It's just that...a coating.

One thing to keep in mind is that the coating is on there to help slow rust. If you grind it off to weld, and even if you weld over it, this coating is destroyed. This welded area will be the first place you will have rusting problems. That's why you see so many mufflers on the sides of roads. Exhaust shops don't care enough to hit some spray "cold galvanizing" on it, or some good spray paint... but you should.

 

So what about the inside of the piping? I have found that the aluminized inside promotes a 'trashy' looking inner bead.

I'm running a 308 rod with the aluminized piping... what do you suggest engloid?

 

You really don't need 308 with aluminized pipe. Something like an Er70S-2 will do fine on it. If you just have 308 around and don't mind using it, it will work fine also though...it's just more expensive.

Don't worry about the "inner bead" on exhaust piping. Exhaust pipes are slip-joints, or socket welds, or lap joints...they do not need to get full penetration. In fact, if you're burning all the way through, you're going too hot or too slow. The inside will have some flaking of the coating though...but that's not a big problem. It will blow out on its own.

 

How about the inner welds for intercooler piping?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PrecisionH23a &raquo;</TD></TR><TR><TD CLASS="quote">How about the inner welds for intercooler piping?</TD></TR></TABLE>

The proper term is the "root." When doing a "butt weld", which is 2 pieces put end to end, you want to get some penetration. Important for IC piping? No. If you can't get a root in there that's less than 1/16" pushed in, then you're better off not trying at all. The last thing you want is a weld that will break, so you want so either get the weld into the seam a good way, or buildup a bit of external reinforcement to help with strength. The second to the last thing you want to happen is for you to have a "dog dick" hanging on the inside of the pipe, disrupting flow.

Most novice welders will not be able to put a smooth root into something like this. My advice for those is to butt the pipes up with as clost to a perfect fit as you can get. Then put 3-4 tacks around it to hold it in place. Then when welding, don't worry about burning into the metal deep, but put a bead that's about 1/16-3/32" tall. (Keep in mind that this is with thin piping). If you have thicker piping, you may want to put about a half-thickness bevel, one pass of weld to fill it, and one pass to "cap" it.

And a word to the wise...ALWAYS TEST FIT YOUR PIECE AFTER YOU GET IT TACKED UP, AND BEFORE WELDING IT SOLID.

 

Engloid,


good advice....we need more people like you in the forum