turbo header madterial?

[RobM]

what aloy stainless steel do you guys use to build turbo headers? 409?

[64duece]

304 is most common. Sometimes I mix 304 bends and 321 collectors / lead pipes. Depends on the application. Some use all 321 but, it's more expensive.

[Blown353]

Inconel is great but spendy-- and spendy is an understatement. LOL.

321 would be my pick given a stout but "limited" budget-- expect $2500-3000 in material for all 321. If welded properly it should last a long, LONG time.

304 would be my next pick.

I wouldn't even consider 409-- my guess is you'll have fairly significant oxidation after a couple drives.

[calforniacuda]

Burns Stainless has an article in their catalogue about header material. Good read.

[RobM]

next question... can i weld 321 with 304 rod? because thats all i have around at the moment

[chicane67]

Use 347 filler rod to weld 321 to 321

Use 308 filler rod to weld 321 to 304

Use 309 filler rod to weld 321 to mild steel

[RobM]

sorry that was a typo i meant to say 309 filler rod. but thanks for the info.

so what would be the effect of welding 321 to 321 with 309 rod? would the welds oxidize?

[RobM]

any tips for welding 321?

[Blown353]

any tips for welding 321?

Look in the fab forum... it's been discussed there in great detail. Summary: clean, clean, and clean some more, use the right tungsten, backpurge the tube, and don't overheat it as you will displace the alloying materials from the weld zone resulting in oxidation/corrosion down the road. If you get the tube joints perfect you can often simply fusion weld the components together (no filler rod.)

[RobM]

well ive started this project... its for a parsche 911.

well see how it handles a few dyno runs and regular street use. I know that the set up will be pushing enough power to get some of the tubing glowing hot.

I back purged most of the welds and i have to say it makes for a much nicer weld. 321 isnt quite as forgiving as mild steel.