Worse Gas Milage w/ Yodude

[Cougar0102]

Hey - I've had my Yodude Dual Exhaust on now for about 3 weeks or so. I wanted to give it some time to be broken in, and think I've given it plenty. My gas milage was at 25.5 before I had it on. Now its at 20.5. I thought it was supposed to increase?

[ProjectCougar]

Have you changed your driving habits? I installed Yo-Dude on Oct 25th and left for CA on oct 27th. Across Country, averaging about 80-85MPH on the highways I was able to maintain an overall average of 26MPG. I played around alot too in TX and AZ trying to see what the car could do. My car only had 4921miles at date of departure so wasn't clearly worked in. I forgot to reset my battery, did you?

[Cougar0102]

As a matter of fact, no. I took my car to Car-X to have the duals installed, and the guy never disconnected the battery. However, last night I disconnected the battery myself when I took that "throttle-hang fix" out. Over the past 50 miles or so, my car's been averaging about 22.5 - 2 more than it was before I disconnected the battery.


And also, if there is good airflow through the exhaust, gas millage SHOULD get worse, right? So if Yodude gives you extra gas millage, where does the extra horsepower come in?

[NorCalCoug]

In this particular case, lowering the backpressure by giving the exhaust 'more holes' to leave the exhaust system shouldn't /reduce/ gas mileage. An exhaust system wouldn't be giving you that much of a mileage boost in any case, but if you look at it this way:

Say without the YoDude, you take 2 driblets(made up unit) of fuel to put out 150 horse to the wheels. Now, it would be higher, if there was less backpressure.
Now, with the YoDude, you take that same 2 driblets of fuel, and you suddenly get 152 horse to the wheels, because you've lowered the backpressure with a higher flow exhaust. So, for the same fuel expended, you get more horsepower. Does this make sense? Or am I blowing smoke out of my ass? I'm no mechanic, but I do try to understand logic, and the basics of how a car works... :)

[Andy]

It might be the sound making you want to rev the engine more, =ing lower gas mileage. I know that is what happened in my case. I just LOVE hearing my YoDude!!:)

[NorCalCoug]

<< It might be the sound making you want to rev the engine more, =ing lower gas mileage. I know that is what happened in my case. I just LOVE hearing my YoDude!!:) >>



LOL. WARNING: YoDude may reduce your gas mileage due to frequent engine revving? :)

[Andy]

No doubt!!:)
I just LOVE revving my YoDude. I can't stop.....

[Afuente]

Must be the nice rumble it makes cause if I get to pull up to a light next to some import....I can't help myself but rev the engine just a bit. Actually, in my case, I'll pull up next to anything and rev the engine just to hear it.

I'm starting to get better gas mileage from 20mpg when the YoDude was first installed and now I think it's back up to 25mpg.

,Jer

[FordMan]

That's correct, Afuente will rev the engine next to a school bus, because it might want to race!!!:)

Troy T

[AtomicInternet]

I've been putting in higher octane gas and getting better mileage.

Now I'm going to follow that with a discalaimer:
Everything I know about Octane says it makes no diff in performance/fuel economy/etc. Only resistance to knock, which my engine has never knocked so I always ran at 87 octane. However, since gas prices plummeted after 9/11 I've been putting in 89 octane for giggles. My fuel economy which was 27.8 BEFORE YoDude and went down to 23.3 AFTER YoDude has now recovered to 25.4. If gas prices stay low I'm going to start running 93 octane and see if I get any better.

Just something to try while gas prices are low. My guess is the computer is taking advantage of the octane and running leaner.

[Afuente]

I try to run 93 Octane anyway. Of course, in Woodbridge, VA the gas prices are down to $.89 for Regular and about $1.07 for Super (93).

I've also thrown a bottle of Prestone 0-60 Boost (Kmart or Walmart), once in a while. Besides the tiny amount of extra boost it might help w/mileage too.

,Jeremy

[BigKat]

I always thought that running a higher octane fuel defeated the purpose of trying to get better gas mileage, b/c you have to spend the extra $ for the premium gas anyways.
I didn't take the time to do the math, nor did I actually try it myself.

I did read this article in C&D where they put premium gas in an Accord that's designed for regular, and the engine actually made less power on premium

[ZERO]

when i just had the KKM i put high octane in my car just for experimentation and it felt sluggish and crappy. now if i put high octane in it gives it a considerable jump. why? well now i got the SVT upper and yodude exhaust so stuff flows a heckuvalot more freely

[Fieldsexp]

Well with mine it seems that city driving I lost maybe 1 or 2 miles per gallon. But then on highway driving I gain a few. Driving about 185 miles on a fresh tank at 80 miles an hour I was getting about 29 miles per gallon and I have an atx. So its just a little give and take

[Tilran]

are you guys calculating these MPG or are you looking at what the car tells you from our little read outs? cuz i am hearing people get 25-29MPG! with automatics!!! i have a MTX and the highest i have gotten was 25.2 and that was driving 2 hours without stoping.

normal street driving i get about 20-23.5 MPG...what the hell are you guys doing to get such high MPG when even our window sticker says we get 20city 24highway

lol

oh and our engines are not ment for high octane btw, if you dont believe me go ask your dealer or a ford mechanic, putting in 93 oct will acctully degrade your engine after a while.

2000 MTX V6

[Fern]

I have a KKM and Borla and I get approx 25 mpg in city driving with my V6-MTX driving normally. Before the mods I would get like 20 or 21 mpg city. But when I drive frisky, I'll be lucky to get over 18 mpg.

29 mpg with an automatic seems a little hard to believe.

[EricF]

Tilran, supprisingly enough the ATX cougars are rated better for MPG than the MTX crowd(us)

Although with my V6 MTX I've been able to muster 26mpg on long highway trips.
With KKM and Borla.

[Andy]

The only time I have EVER been able to top 26MPG is on the way to and from Cougarfest.
I have a lead foot...:biggrin:

[Fern]

26 highway? I'm getting 30 - 31 mpg on the highway. However, the speed limit on highways were I live is 100 km/h... that's only 62 mph and I usually cruise at around 110 km/h. I wonder how much I'd get in Portugal on the highway at a constant 200+ km/h. :) On my Contour, I get about 28 mpg on the highway but that car has almost 120,000 km on the clock.

ATX's are rated higher by Ford, but you can really milk every last drop of gas with an MTX if you wanted to in city driving.

[Tilran]

ATX rated higher then MTX? eeeep, thats odd....god i cant imagine getting 30MPG on highway....ok thats it, after using half my tank im gonna shut off the engine put it out of gear and push the rest of the way!!...that should up my MPG right? hrmmm *just a thoght*