Header: Stainless vs. Mild

JunpoweR · 02-20-2009, 06:38 AM

The moisture evaporates from the headers heating up.
I don't see how it can stay logged inbetween the wrap and header.
Fiberglass and Ceramic preg Fiberglass wrap (Do not use anything but Ceramic/Fiberglass wrap for rotarys)cannot trap water if you heat it up and while driving even if water gets onto the wrap it will evaporate in seconds due to heat.
I can imagine having wrap around mild or SS can reach higher tempatures, remember, when almost any type of metal is heated up it expands to a certian point and if overheated it will shrinking more than it expanded causing cracks and warping. All this is caused by many different factors, Pipe gauge, weld quality, material choice. Exhaust wrap is old school technology, get a good quality coating from JetHot.

SS304 had many advantages over Mild Steel.
Lighter - Stronger - Higher Temp and Corossion resistance.
The only advantage I can see that Mild Steel has is it expands and shrinks better because is is a softer steel than 304SS.

The only other way I can imagine why water would be a problem is when your headers are very hot and you hit a puddle and water splashes onto the hot exhaust metal cooling it down to fast causing warps and cracks in welding. Remember the weld is always harder than the metal around it. During welding, a filler rod is used causing the weld to cool and introducing a new alloy into the welding pool making that area harder than the steel being welded together, thus less expansion/shringage in the welded areas causing cracks and warping in those areas.

I would go with SS and JetHot Coatings.

StarSpeedRacing will be making SS304 Medium Primary Header and Mid pipe Combo that bolts up to any bolt on cat back, check out the GB section soon.

02-20-2009, 06:38 AM	#21
JunpoweR Rotary Fan in Training Join Date: May 2008 Posts: 66 Rep Power: 0	The moisture evaporates from the headers heating up. I don't see how it can stay logged inbetween the wrap and header. Fiberglass and Ceramic preg Fiberglass wrap (Do not use anything but Ceramic/Fiberglass wrap for rotarys)cannot trap water if you heat it up and while driving even if water gets onto the wrap it will evaporate in seconds due to heat. I can imagine having wrap around mild or SS can reach higher tempatures, remember, when almost any type of metal is heated up it expands to a certian point and if overheated it will shrinking more than it expanded causing cracks and warping. All this is caused by many different factors, Pipe gauge, weld quality, material choice. Exhaust wrap is old school technology, get a good quality coating from JetHot. SS304 had many advantages over Mild Steel. Lighter - Stronger - Higher Temp and Corossion resistance. The only advantage I can see that Mild Steel has is it expands and shrinks better because is is a softer steel than 304SS. The only other way I can imagine why water would be a problem is when your headers are very hot and you hit a puddle and water splashes onto the hot exhaust metal cooling it down to fast causing warps and cracks in welding. Remember the weld is always harder than the metal around it. During welding, a filler rod is used causing the weld to cool and introducing a new alloy into the welding pool making that area harder than the steel being welded together, thus less expansion/shringage in the welded areas causing cracks and warping in those areas. I would go with SS and JetHot Coatings. StarSpeedRacing will be making SS304 Medium Primary Header and Mid pipe Combo that bolts up to any bolt on cat back, check out the GB section soon. __________________ --^v--JunpoweR--^v-- "90 GTUs Crystal White GT35 WB TA Project "90 GTUs Brilliant Black Restoration 1984 GSL-SE Daily Last edited by JunpoweR; 02-20-2009 at 06:48 AM.