I just recenty bought a helix catted downpipe, and was considering wrapping it with some high temp header wrap. I was wondering if i should wrap the cat too. would holding the hot gasses in the cat cause it to burn up? should I even wrap any of the down pipe, for the same reason? Just wondering. I still need to pass emissions so a burnt up cat wont do me any good

 

if the cat isnt carb legal it isnt legal

you dont need to keep the heat in after the turbo

 

Can't people pass a sniffer test with a high flow though? I'm not worried about the visual, I've seen them do the inspection, they dont even pop the hood, or look under the car around here. what do you mean you dont need to keep the heat in after the turbo? wont keeping the exhaust air hot increase the air flow? isn't that why others wrapp thier downpipes? And why companies sell coated downpipes. I'm just wondering if keeping the hot air in the pipe is going to burn up the cat.

 

do you have an up pipe cat?

 

I'm putting an hks up pipe in whenever i install the downpipe.

 

oh i was going to say you can probablly get away with catless down pipe but catted up

the pipe on teh down pipe is bigger than the up pipe so some velocity is lost there

up pipe is what you would want to do

 

no, it will not.

a coated or wrapped DP will keep heat transmission from pipe to TMIC down to a minimum.

it will keep exhaust gas velocity high.

it will also help the cat do it's job more efficiently. they need heat to catalyze.

my bosal shorty has been wrapped for over 2 years. looks fine.