When I was redoing all the junk under the hood I got stuck on what headers to get. I had a set of Downey chrome headers on my old Toy and don't remember ever hearing them, but since I was getting pretty much everything from one outfit I finally decided to go with theirs even though they used 16 gauge pipe instead of 14. I thought 14 might be a bit quieter, but not much and it seemed like everywhere I looked other headers were chromed and I don't care if it shines I just want it to work.
Big mistake. I sound like a tractor with beer cans for exhaust going down the road and I can't stand it any longer!
Seems like I have heard in the past of header tape or something similar that hot rodders use to dress up and/or quiet the headers.
Does anybody know if something like that would be OK on a Toy? I'm mostly concerned if it in any way might effect the o2 sensor assuming there would be increased heat going through the pipes since the tape would act as an insulator. If it doesn't cause any problems, does anybody know where I could find something like that?
Any opines?

 

http://www.thermotec.com/tt/

They make good stuff. I used one of their kits to wrap my turbo on my Supra and it lowered the underhood temps by at least 70 degrees.

Hope this helps.
Dr. Z

 

Hi everyone. Nice board you got here. My first post.

The reason most hot rodders use header wrapping is to insulate them thermally, because it will keep the exhaust gasses hotter so they exit more efficiently. Generally speaking, hot rodders don't give two ˟˟˟˟s about noise, so header wraps aren't really designed with noise reduction in mind, although they may have a small effect. The extra heat retained in the headers also increases the risks of warping the metal, so some header manufacturers will void any warranty on headers that have been wrapped, so read the fine print, and call whomever made your headers to get their input. If you decide to wrap them Summit Racing, Jeg's or other such shops will have what you're looking for.

-Scott

 

header wrap will trap condensation between the wrap and the metal, which will eventually cause the pipes to rust out.

i promise you that'll be a whole lot louder than what you have now. you shouldn't be getting any extra loud noises coming from the engine bay unless you have a leak. what kind of exhaust setup do you have now?

 

I just went to the LCEngineering website so I could provide a link to the headers I have (bought them about 3yrs ago) and discovered that they have changed over to stainless and 14 gauge instead of the 16 gauge pipe on my headers. I think the real issue is the thinwalled pipe. When the exhaust hits the top bend in the header it resonates. I even noticed an increased amount of sound when I got the K&N filter charger kit and started getting more air through the motor (even taking into account the increased under hood noise of an open breather). The headers are followed up by 2 1/4" pipe, free flow cat and Pro Flow chambered muffler. You can sure hear me coming when I push that pedal a little farther down than need be LOL!
At first I thought it might be the air injection block plates. I initially reused the old ones off of the stock exhaust manifold and they are somewhat thin. I then made some quick and ugly plates out of 1/4" stock with no luck.
I checked the gaskets yesterday looking for burns from exhaust leaks and don't see any. Besides which, an exhaust leak has a pretty distinctive high pitched ticking sound. This is closer to a popping sound.
If the tape doesn't deaden the noise some, hopefully it will rust out the pipe, then I'll have a really good excuse to go get some thicker walled chrome ones