Re: Help EFXR6 fitted extractors & lost power
I had a heap of trouble with my exhaust. What did they do to your cat?? How does it rev? does it cleanly make it to 5500 revs or does it snuffle etc? If there was a block in the exhaust, it would stutter and carry on at about 3500 revs and not rev any further (depending on how blocked it is) This happened to me when my cat crumbled inside and choked up the flow. The I6 motor usually responds great to exhaust mods. There is definately something wrong. Does it make a whistling noise when you give it to it? Mabye it has something to do with where the oxygen sensor is positioned in the new extractors. Maybe it is not reading too much oxygen (all the oxygen might go to a certain 'chamber' in the extractors), therefore making the mixture rich and explaining the decreased fuel economy and reduced power. My advice is, put it on a dyno and go from there (It will rule out a lot). Get a mixture and horsepower reading and compare it to stock. While its there advance the timing a bit. It should be making at least 10Kw more at the rear wheels than stock. If the mixture is the cause, then look further into the oxygen sensor.
Falcon S, MPFI, red, Resprayed with colour coded bumpers, motorvator extractors, walker hi-flow cat, 2 & 1/2 exhaust system, cold air intake using hi-flow K&N pod filter (heat sheilded), stage 3 crow cam with a vernier cam timing gear. Severly ported and polished EB 4.0L head, shimmed valve springs - compression ratio (9.5:1 +). Making 145rwkw!!