Ok brennamen and i spent all last night getting my edelbrock headers in and i have to say it turned out pretty well... aside from having to use a hacksaw to get the old i-pipe out... it sounds amazing but its still retardedly loud because ive only got it hooked up to the cat, so no i-pipe, no muffler, no exit pipes lol

Theres beeen some pros and cons ive run into and i was hoping someone could clear them up for me since this is the first set of headers ive ever run.

1. Its running cooler than before, not complaining here but i didnt think that a set of headers could have that effect...

2. Its burning gas like crazy, i went from mesa, to fountain hills, out to queen creek and burned 1/4 tank before the swap, coming from QC to mesa i burnt 1/4 as well... anything i could have screwed up to cause this? Or is it possibly because im running an open cat?

3. Feels sort of sluggish at low rpm but when i sped up on the 60 today i just downshifted to fourth and it took off a lot better than it used to, but like i said low end, its kinda bleh

Thats all i can really think of for now but im sure ill find more

TIA

 

Sounds like you might be running in open loop. Do you have the O2 sensor connector plugged in and the O2 sensor screwed all the way into the header. Just a couple of things to double check.

Computer cars also do not like open exhaust. Once you get the rest of the exhaust on there reset your computer. It will run alot better. It may be the exhaust temp is not getting hot enough without the back pressure to turn on your O2 or it is taking a very long time for the O2 to get up to operating temp.

If it's still sluggish and you have poor mileage I can data scan it for you and we will figure out what's going on.

 

I did LTs on my LT1 with an open Y-pipe and everything improved, lowend, topend, mid range everything. It was a right away feeling too. Gas mileage stayed the same.

On my GTP, basically they were shorty-mids, there was a noticeable low end loss. It bugged me so much, I actually sold the headers and just ported the stock manifolds and got a bigger downpipe and my torque came right back. The low end loss, wasn't worth the topend gain for me. But I did gain 1-2mpg with headers.

Like Brian said, about or your mpg loss, your running rich because of the open exhaust. The o2 readings are screwy so it's dumping in waaaay more fuel to compensate. Thats why you have horrible lowend performance too, the engine is being flooded with fuel.

Are the headers brand new? If they are, the coating and material will foul out your o2 sensor and also cause a nice rich condition. Get a new o2 in there, get your exhaust put back together, and reset the o2 and then enjoy the headers.

Hope that makes sense.

 

I'd agree with the open exhaust causing erroneous O2 readings. On my 92 v6->v8 swap, I ran the first few minutes w/ open headers and my wideband O2 read 22:1 at idle speed (impossible, the motor wouldn't run unless it was a diesel). I put Hedman S-bend extensions on and my A/F ratios were a more reasonable 14.3:1 (or there about).

 

the headers were used, theyre edelbrock air tube headers, got em for 150, so they're already broken in pretty well lol its getting better power but the gas thing is kinda annoying

I figured it was the open cat that was killin me, but i need someone who can weld, i had to cut my 3 inch i-pipe so thats gotta be put back together, and i'm running a 3 inch dynomax cat which had square flanges, but i had to switch to a 3 bolt triangle style flange, i only got one side done i had to cut the old flange off, bang it from an oval to a circle and then weld the flange on, now i need to do the same to the other side, as long as i can get the i-pipe in it will be ok cuz i was running w/o a muffler for a good 3 months with no issues so do we know anyone on here thats a welder?

summing it up i need the flange on the cat/ i-pipe welded, then the i-pipe to the part that bows up over the axle done any takers? ill have to get some 3" ID pieces of pipe to compensate for the cuts we made and where they downsized the i-pipe to the old cat

 

nobody??

 

Muffler shop should be able to do that for you.

 

When you run headers the O2 sensor is not going to heat up as much as it used to with the cast iron manifold and the single wire O2 sensors the thirdgens came do not read well or sometimes at all if their not at proper temperature i had this same issue. What you would really benfit from is a 3 wire heated oxygen sensor conversion it is very easy to do and inexpensive and you will see better gas mile age and better throttle response.

 

i think ill look into that, my only real trouble with the gas mileage is when i start the car and take off immediately, ive been letting it reach operating temp and its been good to me so far, i have a friend who works at affordable german whos gonna let me use the shop, he said he'll weld it up for me and let me install it so i got that figured out atleast, for now my only issue is the noise level as long as i stay out of glendale ill be fine with that, i got pulled over the other night and i got a warning about it but mesa PD in my area doesnt care, guess thats a plus about workin for QT, get to know the cops pretty well lol

 

ha ha i know what you mean about the Glendale PD. Their so uptight about that.