I'm not sure how much bhp u will get. yes, it is a noticeable gain. it should be ok if u have cats on but with no cats it is going to be loud. Lou's setup is probably the quietest mod with headers. i recommend checking clublexus for more info.Lowrider-
Roughly how much bhp you think with the PPE headers and hi flow cats the F makes? I understand temperatures and humidity and other things effect this, but i would just like an estimate. I'm getting the PPE headers and cats soon and i would just like to know how much power i should get. Also is this a noticeable gain? Also how loud is the Joe Z exhaust with these mods? I plan on getting the Joe Z exhaust later but I don't want something obnoxiously loud. What is your opinion on the Joe Z exhaust with these mods? Are you glad you chose it over the other aftermarket exhausts available for the F?
If i were to go to a muffler shop and get straight pipes made and welded in would there be a check engine light?