Ok guys, lets talk about making your own down pipes, and whats the best for optimal flow. I'm running a SR stage 2 with a V band setup for 3". I was wondering what would be the best thickness for wall size? Can I just run down to the local exhaust shop, pickup a couple feet of 3" exhaust, some mandrel bends and slap it together? I'm not worried about the welding part or anything like that....but just want to make shure the thickness is thick enough, so it won't melt.

Any other ideas or pointers are gladly welcome. CJ

 

Thats exactly what I did. bought a section of straight and a couple U bends. I woulden't worry about it melting because I have the thin stuff (18g I think) and it's been awsome so far durring the past 1600 miles.

 

Your temps right after the turbo will be around 740-780 and sometimes past 800 celsius, so as long as it is made to handle heat higher than that.

 

CJ,
If you like stainless, get some 304 SS (straight and mandrel bent) 3" exhaust piping. As far as thickness goes, just match the thickness used in the rest of your exhaust system

when do you want to trade the SS hoses?

Jim

 

SS exhaust pipes can be pretty thin. The downpipe that comes with the RX6 turbo kit is very thin and I haven't had any trouble with mine, or heard of other people having trouble with it.

Makers of mild steel exhaust stuff tend to use and recommend thick walls, but I think that may be for durability after some rusting. SS is much less susceptible to corrosion, and perhaps correspondingly can be much thinner without sacrificing longevity.

-Max

 

Well, to be honest, I'm probably going to go with steel. In the 4 years I've owned the car, its seen rain just a couple times. Not to mention, I'm going to have it ceramic coated to help keep the engine compartment a little cooler. So corrosion its realy a factor to me.

I'm going to be at the RPNW meeting this coming week. We could hook up their. Later, CJ

 

i would use at least 16 gauge (.065") thickness

i think it's a good middle ground between weight and strength

 

I use homemade down pipe made from 304 ss from burnsstainless. Just buy two 45's and a section from the stock downpide and get a lip that hooks up to the turbo that uses a v clamp.
After running in the night; that down pipe will glow's bright red hot. But it holds up pretty good.

 

Well maybe a update is in order. I spent $5 on a 40" section of 3" pipe from a local exhuast shop, $5 on two o2 sensor bungs, $16 on a V band flange, then a portalbe bandsaw, a bit of welding, and 3 hours later I have a down pipe.

I'll admit its not the prettiest one outh there, but the bends are nice and gental, and should flow without good a problem. If someone wants, I could put up some pictures.

But it still needs to be ceramic coated....

CJ

 

pics!

 

and where did you get the v band flange and everythign else?

 

http://atpturbo.bigstep.com/item.htm...2&PRID=1390389

The turbo allready had the other side of the V band welded on.

I'll have pictures in a couple days. I still need to do some welding/grinding. CJ