Could current mods cause my car to be running rich?
 

Hey all,

I've got a 2.5 inch straight pipe exhaust with 1 resonator at the midway point, 12v mod, walbro 255 fuel pump, and a BFI with some nifty ducting to the sport filters tip for when on the highway. It's a 5spd. 1997 SC300. The reason I ask if these things can cause it to run richer than normal is because lately I dont know if my foot has gotten heavier or I've just lost all fuel efficiency. The distributor is new, wires pluges all new, just got a new alternator. The car runs great as hell and seriously impresses me when it chirps in second gear. I'm just wondering if these things cause the mpg's to go down? I do not at all mind if I lose mpg's but just curious. Thanks. Also...whats better a cone style filter or those weird bumble bee HKS style filters? Thanks.

Ashtray-

Here's a Foam vs oiled paper discussion.
http://www.thumpertalk.com/forum/arc.../t-160148.html

Also I have owned several airplanes and they all use foam air filters. IDK if it's just the FAA slow to change or if they are better than oiled K&N type paper. They seem to stay with foam. If I had to take a stab at a guess I would say paper flows better but foam catches more silica or sand particles.

IDK about your problem but did you do the 12v mod when you were going turbo and just never switched it back? If I had your mods I would get a wideband even tho you are not turbo. At the very least would put your mind at ease as to if your running too rich or not. And eventually when you go NA-T you'll have it already.