Mpg loss?

[NicholasP]

Could magma flow comps be the reason my mpg is so low? I know obviously I'm led footing it but when I reset it and really try to drive well it still sucks

[ronnie948]

You really need to run a couple or more tankfulls and use pencil & paper to check the milage.

If anything you should be getting better MPG with the Comps.

My gage never said I was getting more then 22/24 mpg but when I checked it 2,103.05 miles I used 70.96 gallons of 87 octane giving me a realistic 29.637 Miles per gallon.

I don't even know why they put that stupid """WRONG READING"" gage on the car. A nice digital speed-o-meter would be better.

Ronnie

[99ford]

Originally Posted by ronnie948

You really need to run a couple or more tankfulls and use pencil & paper to check the milage.

If anything you should be getting better MPG with the Comps.

My gage never said I was getting more then 22/24 mpg but when I checked it 2,103.05 miles I used 70.96 gallons of 87 octane giving me a realistic 29.637 Miles per gallon.

I don't even know why they put that stupid """WRONG READING"" gage on the car. A nice digital speed-o-meter would be better.

Ronnie

I agree with Ronnie every thing in the books suggests increased fuel economy. The pen & paper method is still the only way to determine actual MPG average.

How is your tire pressure, and air-filter condition? Every 15-20,000 on the air filter is recommended to be replaced. And air pressure should be checked every fill up. ( or as the owners manual states once per week.)

[Sanguin]

I don't know how cool it's been down there, but engine warm up is killing my mpg. I'm getting about 1-2mpg less than in the summer on average. They also switch to a different fuel mixture for winter at gas stations. So, don't be too surprised if that is affecting you.

[bucko]

What usually happens when folks install a mod is that the right foot goes into "test it" mode.

Like all are recommending, try a few tank fulls to get an overall reading. Engines should perform better with easier air flow in, and air flow out. However, a set of axle backs are not going to provide you with any big gains in the MPG field by themselves.

The engine just sounds better!

[pwrby4d]

I would use pen and paper method. Obviously you said you are keeping your foot in it so that is most likely the reason but climate change, tire pressure and style of driving are most likely the reason.

[UltArc]

Originally Posted by Sanguin

I don't know how cool it's been down there, but engine warm up is killing my mpg. I'm getting about 1-2mpg less than in the summer on average. They also switch to a different fuel mixture for winter at gas stations. So, don't be too surprised if that is affecting you.

You can always do an upper and or lower grille block, to cut down your Cd and quicken engine warm up time.

[Whitelightning]

Since I've been traveling because of job ill mention this. Some are silly though and just my ways.
I run my tire pressure on my michelin defenders at 36. Max is 45.
I run 2.73 gears and try to let it shift at 2k and under.
I only have a duffle bag of clothes and a longboard on the upper part of the trunk in the back. (Weird sentence)

I fill my tank up regardless.
Use cruise control.
Keep the car of clutter. Clutter =weight. Weight=bad.

Don't let the engine idle for a long time. But in traffic just deal with it.

My computer says 30-32 mpg. I know its off but not sure if its up or down from that. I know the magnaflow comps are like a glorified straight pipe add on. When mine were running with no mufflers, I lost Sooo much mpg due to back pressure. Not sure if you have enough with the comp design. Just assuming

[NicholasP]

Originally Posted by Whitelightning

Since I've been traveling because of job ill mention this. Some are silly though and just my ways.
I run my tire pressure on my michelin defenders at 36. Max is 45.
I run 2.73 gears and try to let it shift at 2k and under.
I only have a duffle bag of clothes and a longboard on the upper part of the trunk in the back. (Weird sentence)

I fill my tank up regardless.
Use cruise control.
Keep the car of clutter. Clutter =weight. Weight=bad.

Don't let the engine idle for a long time. But in traffic just deal with it.

My computer says 30-32 mpg. I know its off but not sure if its up or down from that. I know the magnaflow comps are like a glorified straight pipe add on. When mine were running with no mufflers, I lost Sooo much mpg due to back pressure. Not sure if you have enough with the comp design. Just assuming

Less back pressure = less mpg? I would think less back pressure would make the engine run easier and not have to try as hard to get going?

[bucko]

Great tips on improving MPG mentioned by WhiteLightning. I'll add another. I've had my Mustang for just a bit over 11 months, and have 35K miles on it. I drive daily from Orlando to Tampa, about a 200 mile round trip. I use either Mobile or Shell gasoline, as they have more fuel cleaners/additives mixed with their fuel than other brands. However, with ethenol increasing in the fuel we buy, the additives get less and less, and carbon buildup becomes an issue. Ever run your finger on the inside of your tailpipe? That's the aftermath of the fuels we have nowadays. Every 3000 to 5000 miles, I add a full container of BMW fuel conditioner, as it has a high content of fuel cleaner. Don't need to add it more often, just every 3 to 5 thousand miles. It will cost you 12 bucks for the bottle, but it does a great job of cleaning out carbon buildup and deposits on the valves and throttle body. This will improve your MPG as well.

[ronnie948]

Chevron "TECHRON" works perfect for keeping your injectors etc. clean. You can get it almost anyplace and it is not as expensive as the BMW fuel conditioner. I had A Mini JCW before my Mustang and my Mini/BMW tech put me on to the "TECHRON" about every 5,000 mile due to the JCW carbon build up and gummy injector problems with that particular engine.

Ronnie

[Whitelightning]

Originally Posted by bucko

Great tips on improving MPG mentioned by WhiteLightning. I'll add another. I've had my Mustang for just a bit over 11 months, and have 35K miles on it. I drive daily from Orlando to Tampa, about a 200 mile round trip. I use either Mobile or Shell gasoline, as they have more fuel cleaners/additives mixed with their fuel than other brands. However, with ethenol increasing in the fuel we buy, the additives get less and less, and carbon buildup becomes an issue. Ever run your finger on the inside of your tailpipe? That's the aftermath of the fuels we have nowadays. Every 3000 to 5000 miles, I add a full container of BMW fuel conditioner, as it has a high content of fuel cleaner. Don't need to add it more often, just every 3 to 5 thousand miles. It will cost you 12 bucks for the bottle, but it does a great job of cleaning out carbon buildup and deposits on the valves and throttle body. This will improve your MPG as well.

+1 to shell. I used to use non ethanol. Got a solid two weeks a tank on it. Then thy wanted an arm and a leg for it so I went to she'll ethanol 87 grade. Ever heard of sea foam?

[ronnie948]

Sea Foam is good for after the engine gets clogged up. You are better off using A fuel system cleaner like Techron or STP etc. That is not so harsh and prevents buildup sludge in the first place.

I just used some Sea Foam on Shari's 1966 Mustang a month ago.

Ronnie

[pwrby4d]

oh ya. air/oil catch can. that will help as well. it really keeps all the dirty vapored oil from clogging up the intake and everything below it. i have run one almost since day one (100 miles on car) and it really keeps the intake manifold very clean. you might want to pull your air box off at the throttle body and poke a flashlight in there. most likely your intake manifold has got a lot of oil in it if you havent been using a catch can. You can remove the whole intake manifold and use seafoam to clean it all out... They make cleaners that you spray in there while the car is on but that just pushes all of that crap into your motor... no bueno!

[ronnie948]

pwrby4d oh ya. air/oil catch can. that will help as well. it really keeps all the dirty vapored oil from clogging up the intake and everything below it. i have run one almost since day one (100 miles on car) and it really keeps the intake manifold very clean. you might want to pull your air box off at the throttle body and poke a flashlight in there. most likely your intake manifold has got a lot of oil in it if you havent been using a catch can. You can remove the whole intake manifold and use seafoam to clean it all out... They make cleaners that you spray in there while the car is on but that just pushes all of that crap into your motor... no bueno!

Use a catch can and you will never have a problem.

Very good advise from pwrby4d

Ronnie

[Charlie_santos]

Originally Posted by ronnie948

Use a catch can and you will never have a problem.

Very good advise from pwrby4d

Ronnie

I bought a cheap $16 one from eBay and retro fitted the tubing. Works just as good as the $119 from AM, I'm Gna be buying a second one for the passenger side too

[Whitelightning]

Originally Posted by ronnie948

Sea Foam is good for after the engine gets clogged up. You are better off using A fuel system cleaner like Techron or STP etc. That is not so harsh and prevents buildup sludge in the first place.

I just used some Sea Foam on Shari's 1966 Mustang a month ago.

Ronnie

I used it on my 70 and my last 02 DD and it worked wonders. And cleaning the throttle body

---------- Post added at 11:23 AM ---------- Previous post was at 11:22 AM ----------

Oh and not to mention the air/ heat being off. I don't turn the dial all the way for hot or cold. Just enough to where it touches it so that's way it's like your house, nice and comfy. But for a/c I turn it all the way cold

[99ford]

Originally Posted by Charlie_santos

I bought a cheap $16 one from eBay and retro fitted the tubing. Works just as good as the $119 from AM, I'm Gna be buying a second one for the passenger side too

Do you by chance have a link to the eBay store you bought it at?

I'm curious now. I never heard of that but it makes sense.

[Charlie_santos]

Originally Posted by 99ford

Do you by chance have a link to the eBay store you bought it at?

I'm curious now. I never heard of that but it makes sense.

Seriously you could make a catch can made from a Gatorade bottle, all a catch can does is have a inlet tube go into a can with some sort of a filter then a outlet. My friend made one just for ****s and giggles made out of a sprite bottle and it worked lol

This is the one I bought, it's for Hondas but it's simple and not all JDM looking so it works on my car great

http://bit.ly/Sgrzil

[pwrby4d]

I made one for my last car. Lowes or Home depot stuff. Air compressor water /air cup and a few fittings, a steel scrunchy used to clean pans from the supermarket stuffed in the bottle as a baffle and fuel line hose from auto parts store. Fuel line hose is what you should use. Other hoses will rot out from the petroleum. I think it cost me like 20 bucks and I used stuff that would look good under the hood. Could do it cheaper. This time I got a deal on the JLT can so I got it but I had planned on just making one.

[JAC20]

I was conscious of a trip I just took. Used cruise control and everything. Didn't go above 70. 70% highway on this tank.

Reset the CPU mpg to test how accurate it was. Filled up today and got 26.6 368/13.83.

The cars readout was 26.7 so it was pretty accurate.

Not sure what I need to do to hit 30mpgs but I think I can get better not doing cruise control possibly.

[NicholasP]

Originally Posted by NicholasP

Less back pressure = less mpg? I would think less back pressure would make the engine run easier and not have to try as hard to get going?

??

[99ford]

Originally Posted by NicholasP

??

Seems to me that's physics in reverse, I'm curious to know about this myself.

[Midnight2012]

Originally Posted by NicholasP

??

The proper amount of back pressure can give the best midrange power. Too little back pressure can expend unburnt gas or to say too much gas. This can help top speed horsepower at the expense of midrange. This could equate to worse E.T. In a quarter mile as well. The stock mufflers are tuned for best overall performance and really arent that restrictive. They just have more sound deadening material than say Magnaflows or whatever.

[ronnie948]

The proper amount of back pressure can give the best midrange power. Too little back pressure can expend unburnt gas or to say too much gas. This can help top speed horsepower at the expense of midrange. This could equate to worse E.T. In a quarter mile as well. The stock mufflers are tuned for best overall performance and really aren't that restrictive. They just have more sound deadening material than say Magnaflows or whatever.

That is probably why the stock mufflers are so large and very heavy. They deaden a heck of a lot of sound but still let a lot of exhaust gasses through without much restriction.

My Magnaflow streets are probably about the same flow but they sure sound A lot better,Look much better and are much lighter. I bought them because the stock mufflers just did not seem to have any sound at all. My Magnaflow streets have the nice deep rumble that A Mustang is known for and nice big rolled tips that look like the mufflers came from the factory.

Ronnie

[Midnight2012]

Originally Posted by ronnie948

That is probably why the stock mufflers are so large and very heavy. They deaden a heck of a lot of sound but still let a lot of exhaust gasses through without much restriction.

My Magnaflow streets are probably about the same flow but they sure sound A lot better,Look much better and are much lighter. I bought them because the stock mufflers just did not seem to have any sound at all. My Magnaflow streets have the nice deep rumble that A Mustang is known for and nice big rolled tips that look like the mufflers came from the factory.

Ronnie

Yeah Ronnie I want some Magnaflows myself. Had them on my PT Cruiser and loved them. But my daughter hated the noise. I will go that route someday!

[Whitelightning]

Originally Posted by Midnight2012

The proper amount of back pressure can give the best midrange power. Too little back pressure can expend unburnt gas or to say too much gas. This can help top speed horsepower at the expense of midrange. This could equate to worse E.T. In a quarter mile as well. The stock mufflers are tuned for best overall performance and really arent that restrictive. They just have more sound deadening material than say Magnaflows or whatever.

I ran mine straight for awhile. My cruising rpm is 1.5-2. But when I ran straight it was 3. And it shifted to third instead of 5th to gain power.

[ronnie948]

I'm sure your daughter would like the sound of the Magnaflow Streets. They are not loud but offer A nice deep rumble type sound that is not intrusive or obnoxious. They really only come alive when your floor the go pedal. In normal driving they just sound great but you do have to listen for the sound. Mine have been on my car for over 3,000 miles and now sound better then ever. They are totaley made in stainless steel.

They also look much better then the stock mufflers.

They fill up the cut-out just perfect


The stainless steel rolled tips lookgreat and say Magnaflow on the sides.

Ronnie

[UltArc]

Originally Posted by JAC20

I was conscious of a trip I just took. Used cruise control and everything. Didn't go above 70. 70% highway on this tank.

Reset the CPU mpg to test how accurate it was. Filled up today and got 26.6 368/13.83.

The cars readout was 26.7 so it was pretty accurate.

Not sure what I need to do to hit 30mpgs but I think I can get better not doing cruise control possibly.

Ah, cruise control can really suck for mileage. Hills? I went to southern MD from Cleveland Ohio, doing cruise control AT the speed limit gave me only 34.3 mpg, while driving at 4-9 mph ABOVE the speed limit without cruise control gave me 35.9 mpg. PA was killing fuel for me.

[JAC20]

Originally Posted by UltArc

Ah, cruise control can really suck for mileage. Hills? I went to southern MD from Cleveland Ohio, doing cruise control AT the speed limit gave me only 34.3 mpg, while driving at 4-9 mph ABOVE the speed limit without cruise control gave me 35.9 mpg. PA was killing fuel for me.

Flat interstate mostly. Did pull one mountain. I noticed that using cruise hurt my mpgs and this was the first time I was trying to see what I could get.
On the trip from the boro to Chattanooga I averaged 27.4 highway and went to work and some city driving for 2 days and got 26.6

I think if I redo the same trip without cruise I could get close to 30.

Not too bad. I would guess the 18" wheels and 3:31s and AT hurts slightly as well.

But I bought the car because it looks awesome, has a good amount of HP, and gets pretty good mpgs too.

[Whitelightning]

My cruise control is half my success for my mpg. I use it for up hills and click resume for going down them. That and the 2.73 gears

[UltArc]

Originally Posted by JAC20

Flat interstate mostly. Did pull one mountain. I noticed that using cruise hurt my mpgs and this was the first time I was trying to see what I could get.
On the trip from the boro to Chattanooga I averaged 27.4 highway and went to work and some city driving for 2 days and got 26.6

I think if I redo the same trip without cruise I could get close to 30.

Not too bad. I would guess the 18" wheels and 3:31s and AT hurts slightly as well.

But I bought the car because it looks awesome, has a good amount of HP, and gets pretty good mpgs too.

AT will hurt, and the gears hurt fuel economy, but the 18s help it out. Same reason for me, I can get great mpg when I want, and I can get on it and whip the rear end around when I want, to me it is the best of both worlds.

---------- Post added at 01:25 PM ---------- Previous post was at 01:24 PM ----------

Originally Posted by Whitelightning

My cruise control is half my success for my mpg. I use it for up hills and click resume for going down them. That and the 2.73 gears

Cruise for up hills? If you stop using cruise and just use your foot your mpg will go up. Cruise kills mpg on hills. Do you use any instrumentation?

[bucko]

Cruise will not hurt your MPG. If you ar climing a hill, either your right foot is required to accelerate to climb, or the cruise will do it. It's how well you can train the right foot; tough with the Mustang, as it's fun to drive.

I use my cruise all the time, as it keeps the RPM's at a constant, where as my foot has a tendency to excellerate, slow down, excellerate, slow down. This becomes inconsistant over a long trip. Keeping the engine at a constant speed, and as close or below 2000 RPM as possible will net you the better MPG.

[UltArc]

Originally Posted by bucko

Cruise will not hurt your MPG. If you ar climing a hill, either your right foot is required to accelerate to climb, or the cruise will do it. It's how well you can train the right foot; tough with the Mustang, as it's fun to drive.

I use my cruise all the time, as it keeps the RPM's at a constant, where as my foot has a tendency to excellerate, slow down, excellerate, slow down. This becomes inconsistant over a long trip. Keeping the engine at a constant speed, and as close or below 2000 RPM as possible will net you the better MPG.

Cruise control is NOT better than foot control for hills. Your point is clear and not argued on flat roads, but cruise co.trol on hills is not fuel efficient at all. Cruise wastes so much fuel on hills.

[Whitelightning]

Originally Posted by bucko

Cruise will not hurt your MPG. If you ar climing a hill, either your right foot is required to accelerate to climb, or the cruise will do it. It's how well you can train the right foot; tough with the Mustang, as it's fun to drive.

I use my cruise all the time, as it keeps the RPM's at a constant, where as my foot has a tendency to excellerate, slow down, excellerate, slow down. This becomes inconsistant over a long trip. Keeping the engine at a constant speed, and as close or below 2000 RPM as possible will net you the better MPG.

My thoughts exactly. And don't use the hill assist button. I coast down the hills too its just basically idling. The higher the tach the more fuel being dumped.