Got some questions

[thefisl]

Okay, first off, I recently got my 2.5 cat back hks installed. Now I also put on my stock air box b/c I have to do a smog check. Since doing this my car only gets about 290 miles a tank where it used to almost yield 400!! I understand having the airbox is very restictive but that much?!?! by the by I have new plugs in there NGK 6es gapped to just above .28. I recently also had my head gasket replaced b/c i was leaking oil and i just recently noticed that the space where the head and the block meet right by the exhaust manifold keeps getting an oily film. so I don't know if thats normal or not. should i go talk to the guy who did it and have them re do it? or is that normal? i dont think i could have blown it out or done any damage to it i mean i have the t25 and i ve never seen my boost gauge read above 15 although the gasket is a FELPRO and i didnt install new studs or anything.....so what do you guys think?????? THANKS!!!




ps sorry for the long post...

 

[95TSiNewbie]

Not really sure what your post is asking?? Every mod will hurt fuel mileage slightly, but 110miles is about 7 mpg....that seems hight for any mod other then large turbo. I have never got 400 miles to a tank. With all my current mods, i get 21mpg so roughly 300 miles per tank with tuning.(before was 17-18mpg or 240 miles).
Now for the head gasket i do not have personal experience, but you may have over torqued the head studs??
Hope you figure it out,
Bryan Tracy