I followed Ed Anderson's lead and used 304-SS, schedule 40, from R.B. Wagner (www.rbwagner.com).  From what Ed discovered, the added wall thickness is thick  enough to dissipate the heat.  The main pipe is thinner as the worst of the heat has been dissipated by the time it gets down that far downstream.  He has been running his exhaust system for a long time without any problem.  The drawback is that its heavier than thinwall.  My 20B exhaust system weighs 20#.

Mark S.

  At 07:10 PM 9/16/2003 -0700, you wrote:

what grade of S/S are you using?  my welder who does many race cars says just use std. heavy wall, others claim at least 321, and the cost of inconel is too much.
Kevin Lane  Portland, OR
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