As title really what is everyone using for best results? I will always run braced but its better to ask than do it all twice!
304? 304H? 309S?
Thanks in advance

 

80 views and no replies, must be a useful thread after all!

 

Interesting that no one will put up their suggestions. I mean Honestly do we all think there is some black magic behind producing these parts? I can't believe some of the serious fab guys will not post in here.

 

304L is fine for schedule 10 or schedule 40..
321 ss is best suited for thin gauge manis, like 16ga.

 

See that is what I am talking about. Lets see some good discussion rather than the normal bickering now.

 

I was about to type exactly what silly sohc just typed. If you're building your manifold of schedule 10 or 40 pipe, 304 or 316 will work just fine. But when you get into the thinner materials, you need to start paying attention to the grades, and 321 is the first to come to mind. You will see the 16G tubing manifold on race cars and rally cars, and they usually implement a double slip collector, and proper bracing.

 

Agtronic,
I know it has been posted before, but what are you using for intercooler piping? I have heard food grade but I do not know which exact steel. If you would share that would be awesome. I am asking for those that Might ask because your pipes are always so nice looking and polish up so well.

 

I know what he uses, I'll let him answer... but I've often wondered why you don't do more aluminum IC pipe Markku.

 

Was hoping you would reply. So the main factor in turbo manifolds cracking is what exactly? excessive EGT? on certain types of metal and unbraced?

321 used for aplications with more heat ie antilag? so that would be the H type with more carbon to provide improved high temperature strength?

Its good to be new to something sometimes, all the run of the mill bolt on stuff is getting a tad boring now.

Thanks for your replys

 

Well, the piping I use a lot of is indeed sanitary grade stainless, but what that means is that it's polished to a fine finish inside and out. The inside of this piping looks the same as the outside. It is Canadian made T304 stainless. It is also available in 316L.



It actually comes in boxes like so :



1.5" bends :



It's nice to use for intercooler piping, as it is so pretty, but aluminum is a better choice. I use the stainless mostly because my customers love the look and feel of it.

I also use it on exhausts, even though it's complete overkill. I have a good supplier so I get it cheap, though, lately I have been using "ornamental" stainless, which looks almost the same on the outside, without the polished inside. A little bit cheaper.

I would NOT use any of this stuff for a tubular manifold though. 304 or 316L elbows for me, unless I get a special request for a thin wall manifold.

SCH 10 T304 :

 

It really seems as though it's just not popular here in Quebec. Everyone was mesmorized by all the stainless piping the local shops have been doing for years, and it just stuck. Even though I try to always mention that AL is better for IC tubing, they don't want to hear it. I don't care, I do what people want. I think people really like the tiny welds on the stainless, it looks nicer than the bigger welds on AL.

I'm actually doing an A4 right now, and using 2.75" and 2.25" aluminum tubing. This guy is serious about performance. I'll be posting pics soon.

 

Turbo Gav..

There are bunches of companies in your neck of the woods making manis out of 16ga all the time.. most of the population does business in 16ga over the pond. Some of them make the bends on site right from flat sheet.

 

You would think that with a huge motorsports following, someone would create a new alloy that is specific to what we are looking for.

Oh wait, it's called Inconel, and costs a grip. Damn.

 

and isn't inconel a pita to weld?

 

My buddy works for AIM autosport on the Ford-ridley prototype car which runs in the Rolex series and he says that there inconel headers are always cracking. I know that these headers are in the thousands of dollars. Do they crack because they are made as thin as possible for weight savings? This had asways led me to believe that inconel was a fairly brittle material.

 

The headers cracking could caused by quite a few reasons. Possibly the heat cycling/vibration/bracing/harmonics/etc. I would really like to know why they crack, but that is for a whole different discussion.

 

Weird, and honestly, I don't know much about Inconel as far as weldability goes.

Im thinking, some sort of alloy that can withstand a gazillion degrees and have the strength to weight ratio of carbon fiber, so it can support these 75lb turbos hanging off of them.

Then you need to come up with a better head stud so you don't start ripping those out too.

 

All of your high end motorsport uses supports for turbos/wg's off of inconel. Most guys use .9mm for testing and turbo stuff. F1, ALMS and some Nippon series cars will run .5mm wall inconel for race day. Some open wheel teams will go through three sets of headers per race week. Surprisingly though not much if any of it is welded in a chamber. Just pure argon weld with hydrogen purge with pulse to boot.

 

I'm sure it's because they know they will go through so many anyways...