I suspect that one of the reasons some of the above mentioned techniques/products result in better fuel mileage is that the driver becomes more conscious of the way he's driving when these are added. That being said, I've never believed most of the claims I've read for most of my driving life. Also, the payback is questionable (increased horsepower is another issue and does have payback for trucks). If you do the math on the cost of these alterations vs the increased benefit in fuel costs, I think you'll find it takes a loooong time to break even. Just my two cents worth.
I have replaced the muffler with a Flowmaster seems to help a little not to sure but sounds good the old muffler had a large hole in it so it had to be replaced no it only looks like a grocery getter haha...SAM
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Your Friend Sam In (Southport) Panama City Florida Air#15607
I agree with the "engine is a pump" analogy. With the use of airflow sensors, oxygen feedback systems and computer control in modern engines, the fuel/air mixture ratio remains pretty much constant. The optimum ratio for unleaded gasoline is 14.something to one. It would seem then that the more air that you "pump" through an engine the more fuel that will be mixed with it.
More air/less fuel does, I think, result in a lean condition. But, it’s not likely that today’s systems will allow an engine to run lean, or if it does, it will surely illuminate the malfunction indicator (check engine) lamp. Any gain in fuel mileage, if you are lucky enough to get it, is more than likely achieved by the freer flowing exhaust. That might explain why your fuel mileage fell off when you did away with the straight pipe exhaust.
While I don't drive Detroit Iron, my Sprinter van with it's 2.7 liter 155 HP.....225Ft/Lb torque Mercedes diesel works very well, but was in need of a little 'boost' when I tow the 19CCD to Oregon.
I found a fellow who reprograms the ECU computer for just this purpose. Promised gains of 30 HP and 40Ft/Lb torque (measured by dyno) for the miserly sum of $350. All re-progamming is reversible with a money back warranty if you are not satisfied.
I took the plunge in September while in Oregon this summer. The power increase was immediately noticeable and if you keep your foot off the floor, the mileage went up 1-2 MPG. No black smoke either.
Towing up the big grades in the West was much more peasureable now, with the mileage about the same as before the mod.
Unfortunately (or fortunately, depending on point of view) modern vehicles with computer moderated air/fuel/ignition/transmmission control afford little in the way of efficiency improvement via modification unless your needs are very unusual or you're willing to forego emissions and/or durability standards.
Many, if not most, modern vehicles run a wee tad rich much of the time as a means of self-preservation. On something like the new Hemi that's seriously tweaked by the manufacturer for power, it might well run significantly rich at full-throttle.
There are good reasons for that -- partly that the common buyer of such a powerhouse motor is not really looking for optimum fuel mileage, and partly that it's cheaper and easier to just throw more fuel in than to expect every owner of a new vehicle to assume responsibility for keeping the motor alive when, after all, it's under warranty. The manufacturer surely recognizes that, hype aside, most such vehicles spend 99.97% of their existence ferrying li'l Brittney to soccer practice rather than towing a trailer, and so optimize things toward that satisfaction parameter.
For one willing to tread their own path, it's possible to customize performance to specific needs at the expense of others. That any customizer could claim across-the-board improvements with no downside is pure marketing spin with fingers crossed and lawyers at the ready.
My tow vehicle is and old Jeep Wagoneer. Though it was built in the early eighties, it's a technological throwback to the fifties with a few decades of emissions requirements kludged on top. I was able to double its power while simultaneously neary doubling its fuel efficiency and making it far "cleaner" than before by employing technology not available when the silly old thing was designed -- basically just brought it up to late 20th-century spec. But the days of being able to easily realize such gains are long gone, and good riddance!
Even with the huge improvement I've accomplished on this old rig, payback in purely monetary terms stretches beyond my lifetime (unless gas hits $15/gallon soon or I start a serious life-extending exercise program, both of which seem unlikely).
I don't want to discourage anyone from experimenting in search of their imagined optimal; but doing so with high hopes on any reasonably modern vehicle seems to me akin to pole-vaulting over mouse turds.
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"Don't confuse symmetry with balance". Tom Robbins
Well I have received all products and I have finished installing them. I can say for sure that it definitely has more power, it will now smoke both tires and fishtail sideways when you put the pedal to the metal whereas before it would hardly spin the tire once before catching traction and launching. However this is not my main goal as the Hemi already had more power than I needed. My hope is that with all modifications the accumlative effect will be 3mpg increase( according to all literature I would get 6-7 mile increase so I'm hoping for a little less than half that). Only time will tell. I know it sounds great, not to loud but still very deep and throaty, so much so that I will have to discipline myself not to romp on the gas quite often. I will keep everyone posted as to my mpg increase or lack thereof.
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Different strokes for different folks!
I never learned from a man who agreed with me. Heinlein
A big factor in mileage is the effort required to push the air out of the way. It is proportional to the sqaure of the speed and is also affected by the amount of surface area and aerodynamic shape. The easiest to modify is speed. Go from 30 to 60 and the effort required is quadrupled.
Moderate speeds have other safety and economic advantages as well.
I remember what my Uncle once said when I asked him why he was driving so fast. He said: "I'm nearly out of gas and I want to get to a station before I run out." He was a steam locomotive engineer so he might be excused.
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"Not all who are lost are wondering" say Bill & Heidi
'78 Excella 500,"The Silver Pullit". vacuum over hydraulic disc brakes, center bath, rear twin. '67 Travelall 1200 B 4X4 WBCCI 3737
Well, I unforunately have had to add some more expense to my TV mod's. Whilst I was cutting the old exhaust out with and angle grinder w/cutting wheel I threw some rusted metal under my safety glasses and embedded it into my eye. It was hot so evidently it sunk right into my eye. The opthamologist first attempted to remove with sharp scraping tool, no go. Next he tried some fancy tweezers, no go. Next he says, "I'm going to have to drill it out", wooohhh. One of the more strange sensations I've ever felt, he numbed my eye before the drilling so it didn't really hurt to much but I could still feel the drill going into my eye, weird. Then he tells me " I know it doesn't hurt now but when the numbing drug wears off it will", great. He was right but now I feel better and apparently will not lose any sight because of the mishap. So after co-pays and meds I have to add a couple hundred dollars to the modification expense. From now on I will be wearing safety GOGGLES to do any type of power tool work and I advise y'all to do the same. I wish you all a good night but since no pain med's were prescribed I'm still awake and yapping at y'all. Later.
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Different strokes for different folks!
I never learned from a man who agreed with me. Heinlein
mrmossyone;
The old shrapnel in the eye trick.... I had a friend that carried a piece in his eye since WWII. He was in this tank (he was rather drafted into the Russian army) and some one blew the tank up........ oh well a story for an other time. Anyway to make a long story short, after having this in his eye for 50 years they got it our with a magnet.
Other subject.... I think the best way to get better economy it to drive slower..... not a pleasent thought for some ... but it has physics backing it up.
I have a Ford 2006 Ford F-250 with trubos and a 100,000 Diesel powerplant / drivetrain warranty. Do after market mods to these systems suggested here void the mfg. warranty? The lit I read seems to say it does.
I have a Ford 2006 Ford F-250 with trubos and a 100,000 Diesel powerplant / drivetrain warranty. Do after market mods to these systems suggested here void the mfg. warranty? The lit I read seems to say it does.
All of these mods are fairly easy to reverse if you keep all stock components. I can't remember now which do and which don't, I think one might if they knew you'd had it on. The tuner can set the computer back to stock settings easily, the breather and throttle body spacer would take about 45 minutes to change back and the exhaust is clamped on w/o welds so can also be changed back easily. It's really to early to tell but even with me romping on the go pedal a good bit during this first post-mod tank of gas I have increased intown mpg by 1.3. I will know more after a few tank fulls and w/ me driving normally (which is much more conservative and easy on the gas pedal). I am very eager to see what I get pulling the trailor down to Destin for the can-opener.
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Different strokes for different folks!
I never learned from a man who agreed with me. Heinlein