I have a bolt in/out straight pipe in place of my cat. and i am using 3 bolt flanges for it. They are basicly 3" header reducer flanges. I have regular flowtech paperish gaskets in place right now and they leak a bit. I was looking around and found these "Dead Soft" Aluminum reusible gaskets that claim to seal very well. Would anyone recomend these? I figured maybe if they don't seal perfectly i could smear some orange silicone on them... any thoughts?

 

I have them on my car and they work great. No leaks.

When you put the new gaskets on, make sure you tighten the header bolts down every week for about a month.

I think you are referring to the Percy's brand of aluminum gaskets sold at AutoZone.

 

Another vote for dead soft gaskets. Copper or aluminum will suffice.

I have had great luck with Percy's. They kept my severely warped blowtechs from leaking as much as they should have.

 

You can also use the silicone on your paper gaskets to fix your leak. This also allows you to reuse the gaskets if you have to take the connection apart as the silicone causes the paper gasket NOT to stick to the header or the collector. Make sure your problem isn't caused by the collector flanges being overtightened and now being bent.