AnswerID: 96254 Submitted: Wednesday, Feb 02, 2005 at 13:35
muzzimbidgie
replied:
I have put extractors on two of my forby's. Didn't notice much difference on the first (FJ45) cos I left the standard exhaust as it was. Second time around (FJ62) I had the whole system changed to a two and a quarter inch with quality extractors and was very happy with the difference it made.
Going to an exhaust of a really big diameter can actually have a negetive impact, and my brother can attest to this.
He was advised to go to a two and three quarter inch system with extractors on his HJ62, not only did the dyno result come back as same torque but less power, his fuel consumption also went up !!
We know this, cos on that day he couldn't wait around for them to change things, he had to go to work and wouldn't be back in town for two weeks. When he went back, they farted around with more exhauasts, more dyno runs, same results. In the end he paid them nothing, went elsewhere, had a smaller exhaust put on with better results.
The original bunch were stubbornly saying the only option was BIG BIG BIG.
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