Gas Mileage and Ignition timing relationship... Simple question...
I HATE SCAMMERS!!!!
Joined: Apr 2003
Posts: 196
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From: Outta my mind
Originally posted by Tr0LL
ok..... it's been a few gas fill ups since i posted and i can confirm that lowering my timing does wonders for my gas mileage.... could there be something wrong with my ignition system perhaps?
the thing is..... using a timing light, at 16 degrees at 750rpm, i get 19-24 mpg..... basically crappy gas mileage.....
when lowering the timing to about 14 degrees, it instantly jumps back up to 29-30 mpg and the car feels a lot faster... this is of course with NO other changes....
i tested this for 2 months now..... i would run it at 14 degrees.... 29-30 mpg..... go back to 16 degrees and my gas mileage drops significantly to 19-24mpg....... then just last week i decided to lower it to 14 degrees again and bam... 29 mpg from today's fill up.... my driving varies, but even if i drive like a grandma, i could never hit more than 25mpg with 16 degrees timing.....
??? - i am confused....
oh and i'm using 87 octane btw..... and i have the lower compression b20 which is designed for 87 octane (which is 8.8 or 9.2 compression depending on which b20 theory you believe in)... maybe later i'll test it again at 16 degrees and try 91 octane and see if gas octane is the reason here.....
ok..... it's been a few gas fill ups since i posted and i can confirm that lowering my timing does wonders for my gas mileage.... could there be something wrong with my ignition system perhaps?
the thing is..... using a timing light, at 16 degrees at 750rpm, i get 19-24 mpg..... basically crappy gas mileage.....
when lowering the timing to about 14 degrees, it instantly jumps back up to 29-30 mpg and the car feels a lot faster... this is of course with NO other changes....
i tested this for 2 months now..... i would run it at 14 degrees.... 29-30 mpg..... go back to 16 degrees and my gas mileage drops significantly to 19-24mpg....... then just last week i decided to lower it to 14 degrees again and bam... 29 mpg from today's fill up.... my driving varies, but even if i drive like a grandma, i could never hit more than 25mpg with 16 degrees timing.....
??? - i am confused....
oh and i'm using 87 octane btw..... and i have the lower compression b20 which is designed for 87 octane (which is 8.8 or 9.2 compression depending on which b20 theory you believe in)... maybe later i'll test it again at 16 degrees and try 91 octane and see if gas octane is the reason here.....
Anyways, I don't think there's a problem with your ignition system if you are getting that kind of mileage.
Thanks for the results! :thumbup:
Registered User
Joined: May 2003
Posts: 12
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From: california
how can i tell if my distributor is too advance, advance, retard and too retard...this will really help me out because on my 94 civic ex i only get about 25 mpg...and everytime i pump gas its always like 10.6 or 10.8 gals to fill up...
Registered User
Joined: Jun 2003
Posts: 76
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From: West End of RichmonD Va
I have a 97 D16y8 with 120k miles on it
only engine mods are AEM CAI and i run 89 octane gas with Castrol GTX 5W-30 syntec blend
i have noticed a signifigant loss in gas mileage since i put the AEM CAI on. no matter how i drive (even though i am at WOT all the time) i get around 25-28 mpg at best
before i put the CAI on i was getting 32-37 mpg depeding on how i drove. i put alot of highway miles on the car. i recently put a can of retore in with my oil change, and heard a NOticable amount of vaccuum increase( through the Bypass of the CAI, i can actually here it sucking air in at idle now, while standing over open engine bay, neverheard it before i put the restore in) but i still havent noticed an increase in gas mileage. i know it takes a few tanks before the Restore really starts working. but i am curious as to why my gas milage is so low? i know with the AEM CAI it is a lil more responsive, and i drive a lil harder cause i LOVE hearing VTEC kik in at WOT. but even when i drive like a grandma on highway i still dont get an increase in milage. the Best i can get on a tank of gas is 300 miles. i used to be able to get 400 (still leaveing one gallon of gas in)
what should i do? should i run HIgher OCtane Gas? ie go to 93 or Sunoco's 94? IF i do that will i not be able to go back to 89 octane with out getting pinging? (old myth) i recently had my TIming bElt replaced, and i am guessing that honda reset the timing back to stock 16 degrees i think.
should i advance my timing? like by 2 degrees? will that help with gas mileage as well as make the engine more responsive?
should i advance timing AND run better gas? will that increase the gas mileage, repsonsiveness, and make the car run quicker?
Thanks in Adnvanced
Dan
only engine mods are AEM CAI and i run 89 octane gas with Castrol GTX 5W-30 syntec blend
i have noticed a signifigant loss in gas mileage since i put the AEM CAI on. no matter how i drive (even though i am at WOT all the time) i get around 25-28 mpg at best
before i put the CAI on i was getting 32-37 mpg depeding on how i drove. i put alot of highway miles on the car. i recently put a can of retore in with my oil change, and heard a NOticable amount of vaccuum increase( through the Bypass of the CAI, i can actually here it sucking air in at idle now, while standing over open engine bay, neverheard it before i put the restore in) but i still havent noticed an increase in gas mileage. i know it takes a few tanks before the Restore really starts working. but i am curious as to why my gas milage is so low? i know with the AEM CAI it is a lil more responsive, and i drive a lil harder cause i LOVE hearing VTEC kik in at WOT. but even when i drive like a grandma on highway i still dont get an increase in milage. the Best i can get on a tank of gas is 300 miles. i used to be able to get 400 (still leaveing one gallon of gas in)
what should i do? should i run HIgher OCtane Gas? ie go to 93 or Sunoco's 94? IF i do that will i not be able to go back to 89 octane with out getting pinging? (old myth) i recently had my TIming bElt replaced, and i am guessing that honda reset the timing back to stock 16 degrees i think.
should i advance my timing? like by 2 degrees? will that help with gas mileage as well as make the engine more responsive?
should i advance timing AND run better gas? will that increase the gas mileage, repsonsiveness, and make the car run quicker?
Thanks in Adnvanced
Dan
