From my observation, smsp headers are back purged and has very smooth welds on the inside. RMF headers don't seem to be back purged, does back purging make alot of difference in power?


Modified by Suzukii at 5:40 PM 12/18/2005

 

welding/fab section.....

 

to my understanding its done for weld integrity/strength.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by antone &raquo;</TD></TR><TR><TD CLASS="quote">to my understanding its done for weld integrity/strength.</TD></TR></TABLE>

 

Randy(RMF) offers backpurging as an option. Its not fully need though. You can PM him and ask him about it.

 

Purged weld on the left, non purged on the right.

 

I purge all my stainless welds and weld my collectors in a purge chamber.I don't purge my mild steel headers because the weld is stronger than the metal itself.Also the weld on the inside doesn't effect the power .You must have been looking at a stainless SMS and a mild steel RMF.

 

thanks for explaination. I was under the impression that your headers are all not back purged, since most of the rmf headers the users post on HT are the mild steel versions and the recent photo that vteckidd posted showed non-backpurged welds.

So back purging does not really improve flow? You're probably right, since your mild steel headers did so well in the header test.

Conclusion: mild steel headers don't really need to be backpurged, since the steel is already weaker than the welds itself and backpurging does not affect flow much anyways, but stainless steel will benefit from backpurging for the added strength and since its stainless steel and more expensive, backpurging it for the lesser turbulance, why not?

 

I purge mild steel and stainless steel. I don't like porosity in any welds.

Here's a decent site for more info http://www.weldingengineer.com and specifically http://www.weldingengineer.com..._.htm

Some better pictures of the above example.

 

I don't purge my mild steel and if you say you do Dave then you are the only person that I have ever heard of doing that .In the 30+ years that I have been making headers.And your pics are SS not mild steel.And when you sub your headers out do they purge the mild steel ones also?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RMF &raquo;</TD></TR><TR><TD CLASS="quote">I don't purge my mild steel and if you say you do Dave then you are the only person that I have ever heard of doing that .In the 30+ years that I have been making headers.And your pics are SS not mild steel.And when you sub your headers out do they purge the mild steel ones also?</TD></TR></TABLE>

At a minimum we purge all the butt welds in SMSP headers, mild steel or stainless. I see no reason to cut costs by not purging one material over another when we invest our labor and put my company name on the product. In almost 6 years in business, I know of only 1 header that cracked, it was one of my first D series I built back in 2000 for an ITA car. The butt weld at a transition cracked on the collector outlet after an off track excursion. It was mild steel. The customer told me about it but didn't send it back for repair because I assume they took responsibility for the break.

If one doesn't purge a butt weld then I think you would need to go back and clean the inside of the weld up, but if you purge it then you wouldn't have to and you'd also get a stronger weld. The old win-win situation.

 

RMF=real ***** f_ucker

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by animal chin &raquo;</TD></TR><TR><TD CLASS="quote">RMF=real ***** f_ucker
</TD></TR></TABLE>


lol

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by animal chin &raquo;</TD></TR><TR><TD CLASS="quote">RMF=real ***** f_ucker
</TD></TR></TABLE>
RMF=RUDE ***** (You know the rest)
Well Dave ,I have never had a weld crack.I have had the tubing crack.But never a weld.I would say you do it your way and I'll do it mine.Nice try though.

 

You guys are comedians

 

I back-purge all the time. Except when welding. Must be the Hot sauce.

 

lol !!!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DonF &raquo;</TD></TR><TR><TD CLASS="quote">I back-purge all the time. Except when welding. Must be the Hot sauce. </TD></TR></TABLE>

That right there is a good quote, so I had to do it!