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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Which gas or Octane Boost help with smog?

  • Thread starter Thread starter Sicarius428
  • Start date Start date Feb 5, 2004
S

Sicarius428

Active Member
Jan 6, 2004
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49
Feb 5, 2004
#1
  • Feb 5, 2004
  • #1
Was curious if anything will help with smog. I have an appointment tomorrow and I want to make sure that everything will be good. Thanks for any info.
Kevin
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
17
89
Dallas, GA
Feb 5, 2004
#2
  • Feb 5, 2004
  • #2
I don't think any will. I've heard that putting rubbing alchohol in the tank will help, but before you do all this, try to pass as is.
 
S

sleeper89

New Member
Nov 18, 2002
388
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0
Toronto, Ontario
Feb 5, 2004
#3
  • Feb 5, 2004
  • #3
no fuel can make you pass, but running the appropriate fuel will help your car to run properly. that is, DO NOT run premium fuel on a stock mustang, it's a waste of $, fuel, and it will pollute the environment. if your car runs on 87octane without detonation that is what you should run. when running higher octane than required the fuel doesn't burn completely which in turn screws the emissions.

other things to note: do a complete tune up to your spark system and drive the bags off your car to heat the cats up nicely immediately before you strap her down for the test.

i don't recommend adding anything to your fuel. if your car is running right it will pass, if it doesn't pass, it needs a tune anyway.

cool?

-steve
 
S

Sicarius428

Active Member
Jan 6, 2004
2,085
5
49
Feb 5, 2004
#4
  • Feb 5, 2004
  • #4
Thanks for the replies. I will run the piss out of the car beforehand. I only ask because I am bringing the car out of non-op and the previous owner blew the head gasket. Needless to say I got Trick Flow Street Heads, Street Heat Heat Intake, #1 Trick flow cam, Under Drive pullies, MSD 6AL, Mass Air, Throttle Body, Headers... and oh ya head gaskets to replace the busted ones. I thought the #1 cam was smog legal but turns out I was mistaken so that is really my only worry. I have the stock H pipes(ran out of money) so any little bit will help with smog in my case.
Kevin
 

HyPer-50

Member
Jun 26, 2003
377
0
16
Woodstock, GA
Feb 5, 2004
#5
  • Feb 5, 2004
  • #5
sleeper89 said:
no fuel can make you pass, but running the appropriate fuel will help your car to run properly. that is, DO NOT run premium fuel on a stock mustang, it's a waste of $, fuel, and it will pollute the environment. if your car runs on 87octane without detonation that is what you should run. when running higher octane than required the fuel doesn't burn completely which in turn screws the emissions.

other things to note: do a complete tune up to your spark system and drive the bags off your car to heat the cats up nicely immediately before you strap her down for the test.

i don't recommend adding anything to your fuel. if your car is running right it will pass, if it doesn't pass, it needs a tune anyway.

cool?

-steve
Click to expand...

Off-topic, but what do you consider a stock mustang? I run 92 octane in mine, would you suggest I downgrade (money not an issue) to a lower octane?
 
S

sleeper89

New Member
Nov 18, 2002
388
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0
Toronto, Ontario
Feb 5, 2004
#6
  • Feb 5, 2004
  • #6
HyPer-50 said:
Off-topic, but what do you consider a stock mustang? I run 92 octane in mine, would you suggest I downgrade (money not an issue) to a lower octane?
Click to expand...

well, that was actually a pretty poor statement on my part because even a 100% stock mustang with bumped timing could need premium fuel. when considering octane requirements i take timing and compression into account primarily, but there are other factors as well. although many would still consider yours a *mild* street combo, it still deviates from stock substantially. for this reason i recommend filling your tank with premium fuel and set your timing using that. the premise is a car that is designed for 87 octane (ie stock 5L with stock timing) you don't want the fuel to burn slower. now if you take that same car, put in 93 octane, and bump the timing up to take advantage of the higher octane you will have a car that is *tuned* (sort of) for the higher octane. this is how off the shelf chips work.

this isn't the best explanation but i'm at work. if you have more ??'s feel free to pm me.

-steve
 
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