to blown au, when you talk about headers are you talking about the short ones where they hook straight up to the cat, i bought pacemaker extractors the longer ones, and now my auxr6 runs like shit. no power increase at all and absolutely shit fuel economy it has a big flat spot under 2000rpm the ford guy says it's from cutting and shifting the cat back a few other guys reckon it could be the o2 sensor, any thoughts on which type of header i should be using and where do i go from here?
Is your car auto or manual?
I have a similar system on my ED XR6, with the cat moved under the car, it is a 3" cat. Its been on there for five years, new cat last year, NO cat prior to that(i lived in the Territory were it was sort of legal to have no cat). I have never had a problemwith the system as it was.The only problem was an O2 sensor that shit it self(with similar symtoms to what you have described) put in a new O2 sensor and all was great.
Hope it helps.
Pacemakers.. are the best way to go. They are easily the best on the market. Best way to go for exhaust ask the place where you are going. Ask for the best they recomend and if you dont like what they say. Go somewhere else. The system i wanted for my XR8, one place wanted $3500 for the same system i have now, that cost $1600. And i dont think there is a person that doesnt like the note coming out at the rear. So shop around.
jimmantgaris: have you had the car dyno'd....this always tells you waht the problem is, get them to graph your AFR along with power. I had my EF dyno'd after fitting my exhaust (2.5in, pacemakers) and cam (crow stage2) and I was not happy with the way it drove, seems very sluggish and then comes on strong at 4000rpm. The dyno told me:
1. The car WAS making much more power 190rwhp
2. My AFR are sooo rich its not funny as bad as 10:1
3. I had a HUGE peak after 4000 because the injectors were running out of flow thus leaning it off to about 12:1
to delta. well after getting the o2 sensor checked out ok new plugs new k&n filter injectors cleaned still poor performance and even worse fuel economy i'm off to the dyno have to take day off work to get the car up there but i've had enough will let you know what problem is