I don't know if ya'll read the f-bod forums much, but I read a lot of them have problems with long tube headers throwing heater codes on the o2 sensor. I don't remember the code number. I was having the same problem on my black truck with the headers on it.

Reason for this happening is the headers move the o2 sensors a good bit further back away from where it is stock. The o2 sensor doesn't get hot enough so sometimes it will throw an o2 heater code. It will make it run fairly rich as well since the o2 sensor isn't getting accurate readings. This is the most annoying thing for me and to blame for my at best 11mpg in the city, 7 or 8 pulling a trailer if I was lucky.

Since I got the headers coated and put them on the new truck, the exhaust still smells like it should and not near as overpowering as it was on the black truck. I haven't had the chance to check mileage yet, and can't this tank since it was running so rich it would foul out the plugs in about 20 miles or so.

The headers being coated keeps all the heat inside the header keeping the exhaust hotter than it was before they were coated. Since the exhaust stays hotter longer, the o2 sensors are getting plenty hot as well, which results in a good reading. Some of the f-bod guys were splicing in a new set of rear o2's in place of the front ones, since they have a little more tolerance than the original front ones.

Moral of the story .. if you get long tube headers, make sure they are coated, you won't have as much of a chance to have one that will throw codes.

Don't the ASM's come coated already?

 

interesting info. yes the asm's come coated.

 

hmmm. would that header wrap stuff for dragsters keep more heat in as well? so where exactly are the pre-cat O2 sensors moved to with headers? because ive seen ASM goes really close to the cats

 

You are right .. the ASM's move them close to the cats. Since the header tubes would be to restrictive and it would get an inaccurate reading for the other 3 cylinders, you can't put the o2 sensor in the tube. They have to be in the collector area.

I think the wrap isn't to good for your headers cause of how it works. I'm not sure on that one, but I know TOG headers are warranted for life unless you wrap them.

 

yeah i just saw that header wrap in summit, wondered if its worth anything.

as of right now im leaning more towards TOG headers. you only had to move your pre-cat sensors back a little bit right? got any pics of your Y pipe/cat area?
thanks

 

I recall reading that the problem with the wrapping is rust. Condensation occurs as they cool down and gets trapped by the wrap.

 

http://bettie.homeip.net/atvpics/Tru...t/100_0483.JPG
http://bettie.homeip.net/atvpics/Tru...t/100_0485.JPG

There are a couple of pics of them on the old truck. I don't have any updated pics yet. The ASM's are a little longer I think. They also come coated. If you do get the TOG's get them coated.

I think the quality of the TOG's is a little better since they use thicker parts than most other headers. They also use stepped tubing so it gets the same pressure on wach tube without having to have the funky look of the equal length headers. Of course .. that is up for debate since I don't know much about the ASM's.

 

thanks for the pics. what got that truck so rusty under there....man

 

i was at thunder racing and was talking to jeff and said something about how i wanted to wrap my headers so i would have even less under hood heat. He told me that it is not a good idea because they carbon steel and that they will get so hot it cooks the carbon out of them. i dont remember what he said happens the. May of been something like they will get weak and posibly crack or something i dont remember.

 

It was a 4wd and I drove it as such before I put the blower on. It got covered several times in it's life.