Is it ok to join stainless 321 to 304?

[turbovanman²]

It seems T304 isn't the choice for turbo manifolds, it tends to crack, so if I use some T321, then I can reduce the chance of cracking at the flange.

Anyone know of a good source, I need oval for the TIII's port, I found Burns but they want stupid money for Oval but their straight stuff is cheap. I need like 2 feet of it.

[BadAssPerformance]

304 works find... a lot of the cracking has more to do with how well it is welded.

[turbovanman²]

304 works find... a lot of the cracking has more to do with how well it is welded.

I found a few articles that say its a bad material to use, hence the cracking, too much Chromium I believe.

One guy said to bake at 1900 deg at 30 mins to purge it.

Ok, good source of T304 pipe, oval or straight,

[GLHNSLHT2]

I got several compliments on how well my header was welded. Guess what. 3 months of driving around and it's cracked. Right on the side of the weld. The head flange is also warped pretty bad. I don't know what I'm gonna do about it. I've thought about machining a new T304 flange that's 1/2" thick instead of the just over 3/8" it is, adding straps and heavily welding it so it's mostly weld at the place where it cracked. I'm not happy, I paid a lot of money for it. Invested more into having it coated to keep heat out of it, used my turbo support bracket and it still cracked.

I'd love to have one done in 321 but I don't think I can afford it or justify it. Might as well just drop on the NOS masi head and make more power for the same price.

[BadAssPerformance]

Ouch

[turbovanman²]

I got several compliments on how well my header was welded. Guess what. 3 months of driving around and it's cracked. Right on the side of the weld. The head flange is also warped pretty bad. I don't know what I'm gonna do about it. I've thought about machining a new T304 flange that's 1/2" thick instead of the just over 3/8" it is, adding straps and heavily welding it so it's mostly weld at the place where it cracked. I'm not happy, I paid a lot of money for it. Invested more into having it coated to keep heat out of it, used my turbo support bracket and it still cracked.

I'd love to have one done in 321 but I don't think I can afford it or justify it. Might as well just drop on the NOS masi head and make more power for the same price.

Pics? Was it made out of 304?

[Mopar318]

I found a few articles that say its a bad material to use, hence the cracking, too much Chromium I believe.

One guy said to bake at 1900 deg at 30 mins to purge it.

Ok, good source of T304 pipe, oval or straight,

mandrelbends.com

Also Ive used 304 for a number of manifold. Even the flanges. It wont crack...people just cant weld and blame it on the material!

[bakes]

Also alot of people dont pre heat the area before welding

[turbovanman²]

mandrelbends.com

Also Ive used 304 for a number of manifold. Even the flanges. It wont crack...people just cant weld and blame it on the material!

Would I be better off using schedule 10 304 pipe or 16 gauge 304?

http://www.mandrelbends.com/tube-pip...-tube-302.html

http://www.mandrelbends.com/tube-pip...-pipe-447.html

[bakes]

use the thicker

[turbovanman²]

I'll see if Metal Mart has a few feet, if not, I'll order it up on Monday. Need to get this shitt moving. Block should be back next week but won't have time to touch it, Iron Maiden on Thursday, then leaving Friday to Portland bike racing for the weekend-wanna go, lol.

[Mopar318]

shcedule 10 and support it with a bracket.

[GLHNSLHT2]

the link to the schedule 10 is just straight stuff, where do you get bends of schedule 10?/

[Mopar318]

the link to the schedule 10 is just straight stuff, where do you get bends of schedule 10?/

acestainless.com

Go to shedule 10 pipe, then 304 stainless. They are priced really goo.

[Mopar318]

If you are mig welding a 304 manifold with thick stuff im not sure how well it will work. Maybe thats the problem with some people. You cant get the same penetration and as clean weld with a mig.

I do a fusion pass with a backpurging. (just a Tee off the low pressure side into the back side of the weld)

Then I do a pas with filler rod with no back purge.

[turbovanman²]

the link to the schedule 10 is just straight stuff, where do you get bends of schedule 10?/

Al I need is straight stuff, just need to made some new pipes aprox 2-3 inches long, weld to the TIII flange, cut off the 240 flange, then weld the pipes to the header.

If you are mig welding a 304 manifold with thick stuff im not sure how well it will work. Maybe thats the problem with some people. You cant get the same penetration and as clean weld with a mig.

I do a fusion pass with a backpurging. (just a Tee off the low pressure side into the back side of the weld)

Then I do a pas with filler rod with no back purge.

I won't be doing it, the guy I use has all that stuff, they build headers etc for their race and customer Rotary's.

[83rampage]

Had guy at work forward to me this link.

Not sure if this is the cause of the cracking problem, but it does make sense. Welding procedure is important.

[MR. X]

409 Stainless is supposed to be pretty strong. Its magnetic, but corrosion resistant. Learned it from a fabricator near me. Also, I think people overlook proper bracing of their headers and turbos and that may cause cracking.

[Mopar318]

409 Stainless is supposed to be pretty strong. Its magnetic, but corrosion resistant. Learned it from a fabricator near me. Also, I think people overlook proper bracing of their headers and turbos and that may cause cracking.

Yeah 409 is good stuff, but it does tarnish rather easily. I built the exhaust for my daytona from 409. Downpipe and log is made from 304 though.

304 log



304/409 combo DP

[turbovanman²]

Tarnished isn't a big deal, you can barely see it,