# gas mileage after mods



## sentra_hilo (Apr 23, 2003)

im going to advance my timing this weekend. does advancing affect gas mileage at all? how about with headers and exhaust


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## Exalta (Jan 21, 2003)

Yes, they *do* affect gas mileage...timing, headers, exhaust and a filter greatly affects mileage..

the more power, the more gas needed


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## alexburke21 (Aug 19, 2002)

I got about 42 MPG when i got the car. When I added my intake, it went up to about 47. After exhaust and header I'm right at about 38 MPG.


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## HoloSkull (Jan 30, 2003)

I believe that the only modification that will help your gass milage is a new air intake. Anything else will hit your wallet hard...


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## bugnlv (Jun 24, 2003)

i avg about 33-37 mpg with a wai and adv timing @ 13 degrees. highway i get 40 still  here in sunny cal. does the air in CO make better mileage because its thinner so less fuel is used??


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## Texas96Sentra (Apr 10, 2003)

i am about to advance my timing and wanted to know what octane gas you guys used? if i go to 15 deg should i move up higher octane? or only if i get knock should i get higher octane gas? thanks guys


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## mercer_diamond (Aug 1, 2003)

ya u need to run the highest octane gas u can get or u will mess everything up.


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## bugnlv (Jun 24, 2003)

that is one reason im at 13 degrees i can run 89 if im low on cash but i have to get 89 from cheveron. most acros were fine but i started with some Knocking so 89 at cheveron only for me but yea now that 91 is down to 1.79 things are a lot nicer. the main dif in price i have seen is maybe 1-2.50 dollars a fill up not a whole lot but that is every tank.


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## PatScottAKA99XE (Apr 30, 2002)

Well after intake, exh, and timming I get around 42 even though I drive it hard.


Oh, did I mention weight reduction


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## Brakedust (Jan 23, 2003)

High compression will also increase gas mileage!  . My 11:1 motor averages 35 mpg highway, with a best of almost 37 mpg. And as an afterthought, it runs 14.3's hehehe!!

-Bryan


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## Texas96Sentra (Apr 10, 2003)

thanks for the info, ill fill up wiht higher oct gas next time and then do the timing adjustment


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## copperhead110 (May 12, 2002)

I have a K&N, advanced timing, and cat-back exhaust.

My mileage went from an average to 30 to an average of 33. 90% of the time I'm doing city driving.


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## sentravis (Jul 7, 2002)

well.. since i have you guys here.. instead of searching.. ill be lazy and just ask.. does advancing the timming increase risk of cat. conv. goin bad? Travis


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