I'm going to be building my own exhause and need to know the difference between T304 1.5mm pipe and 316L 1.6288mm pipe.

What's the best option for an exhaust and what is the difference between the 2 grades?

Thanks,

Robert

304 has more chromium and less nickel. I think that the slightly thinner wall thickness would make it easier to work with.

316 is more for corrosive applications.

The "L" in either 304L or 316L means low carbon.

And only "L" types should be welded.

Actually that is not true. We process 20,000+ lbs of 304 S/S a month at work and if the right filler material is used it welds just fine. If your welding 304 S/S you need to use 308L filler rod. We do both spary weld (mig) and tig weld. it welds just fine and we never havy any cracking issues. I built my exhaust system out of 304 S/S and it welded up just fine. Also the dragster in my avaitor has standard 304 headers and have held up great for three years. It is also made of 20ga tubing (for weight saving issues) 16ga is good to a NA car and 14ga is good for a turbo application.

We don't weld 316 so I am not sure what filler rod to use for that. I would have to look in my welding book.

Can you check and let me know what your book says?

I'm leaning towards the 316 as it cheaper for the mnaterials.

Thanks,

Robert

Robert,

You can't be right. 316 is usually about 50% more expensive. I'll be happy to check my book but 304 is WAY LESS EXPENSIVE!!!