hydra forming exhaust

has anyone done it to make an exhaust , im interested at having a go and wondered if there's any correction data as regards sizes etc

Lots of stuff on youtube Dan regarding this topic, doesn't look easy

Word of advice Dan, try a header pipe first ,Mike is quite correct to suggest it is not easy. You might also want to give some thought to the wire spec you use, the flat joint is subject to a lot of flexure when you blow the thing up, easy to crack the joints.

If you do go ahead could you document the whole process, together with a few pics, it will make a great topic to install into the new manual, pioneering stuff!

You might also think about the commercial consequences of perfecting manufacture, a lot of people would eagerly buy a Bantam header pipe, of the correct dimensions?

There are some compelling reasons why a fully blown pipe doesn`t give the results a separate cone pipe does. Blown headers can`t be bettered however!

Trevor

The header section was my main thought Trevor

I did a bit of ferreting around and discovered this image of work in progress. I was particularly struck by the butted joint faces being curled parallel together prior to welding, and inflation. As they say a picture and a thousand words?
Hope it helps!

Trevor

Yes the ones I've seen have that too, about 5 mm on each part does the trick make the weld in the correct direction

Has anyone got a picture of the proper finished article -- I can´t recall ever seeing other than pipes with lots of messy looking welding ...

....`RECALL´did I say -- now what does that word mean? --- humm de hummm what on earth is my name ....

Here you are John, the finished article,

Thank you, Trevor --

Amazing!

Second thoughts ...

Looks too smooth for the Shock-wave to be a shock wave. The parallel portion seems to be bloated but probably
not sufficient to effect the resonance....

Science conquers all -- including doubting feelings.

Cheers!

i think alan brown has hydro formed a header pipe in the past, i could be wrong.

Spot on there John, the smearing of the angle junctions is going to mess with the timing of the pulses being generated, kinda negates the whole purpose in the first place. Just about the only reliable dimension would be the tuned length!

Maybe Alan has Adam, I don`t know, maybe he might care to confirm and offer a few hints and tips to prospective header makers? I do know that Derek has made a couple of attempts with reasonable success!

Trevor