Mileage Monster Build

[mountaineergreen]

I'm a believer in UDP's- I know they helped my Ranger.

 

[rocket5979]

I'm a believer in UDP's- I know they helped my Ranger.

The theory of why UDP's see gains is a pretty simple concept. I am baffled why some people cannot understand that.

 

[Big Jim M]

Rocket there are pluses and minuses to changes from stock. For my OWN use changing the pulley would be a minus...as I drive slowly and in stop and go traffic for the most part. Having a UDP would undoubtedly give me less lectric out of the alternator and less coolant flow in the summer heat. Not to mention less freon in that same heat.
Now if I were keeping the R's at 3,000 and above I could use a UDP without fear.
Lots of stuff is available as a bolt on for our vehicles that have a purpose.. however most of us will never quite meet the purposes criteria. We blindly purchase these items with never a thought as to what the purpose of the item is.

In my case as the engine began to heat up the thermostat would open wider and the coolant pump would have to work harder to pump more coolant to keep the temp where it should be.. So while I was grinning at the fuel I was saving from my install the coolant pump would be working harder eating up my savings.. All the while I wouldn't have a clue as to what was going on in there..

Then as the temp of the coolant began to build up in the radiator the clutch-fan would start using more power to cool the radiator...and there would go some more of my fuel!
All the while I was grinning I prolly would be using MORE fuel, caused by what I still keep thinking was a good idea.
Big JIm

 

[AllanD]

The theory of why UDP's see gains is a pretty simple concept. I am baffled why some people cannot understand that.

Simple? Yes.

Correct? No.

The Concept is simple yet fundementally FLAWED because it simply ignores the contrary factors.

It's like the Man Made global warming deciples that point to the glaciers of Mount Kilamunjaro (speling?) in Africa and claim that the shrinking of the glaciers is because of global warming.

when infact the temperatures on that mountain are unchanged in any data set you care to examine.

the glaciers are shrinking on that mountain because there is less snowfall
to be compressed into ice. and that is because someone cut down the rain forest that provided MOISTURE that could fall as snow.
It isn't warmer, but it is DRIER.

And whatever UDP's do "Gain" it is mostly at HIGHER rpm than "cruising"
And what's left is WHILE accelerating, what remains is tiny indeed and mostly because the people doing the testing want to believe.

I'm not saying you aren't trying to be objective in your testing
I'm saying that you are incapable of being truely objective.
and generally we all have difficulty being objective.

A true "objective" test would be having a driver other than the vehicle's
drive it both with and without UDP's and not informing them of the switch.

It is intuative that spinning the engine accessories more slowly
would reduce drag, but as I outlined above, considering all the
factors reveals that any possible effect can only be a small
fraction of what the optimistic buyers of those things want to believe.

And it's in the sellers interest to make money.

The vehicle manufacturers are scrambling and grasping at straws to save every fraction to meet CAFE and yet many believe if they could spin shit more slowly to save gas they wouldn't try it....

Anyone remember VAP/S?

Yeah, spinning your alternator more slowly might saye you something
but probably only 10% as much as folding in your side mounted Rearview mirrors above 45mph.

Or taking the crossbars off the rooftop road rack on your explorer or bronco2.

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[rocket5979]

Rocket there are pluses and minuses to changes from stock. For my OWN use changing the pulley would be a minus...as I drive slowly and in stop and go traffic for the most part. Having a UDP would undoubtedly give me less lectric out of the alternator and less coolant flow in the summer heat. Not to mention less freon in that same heat.
Now if I were keeping the R's at 3,000 and above I could use a UDP without fear.
Lots of stuff is available as a bolt on for our vehicles that have a purpose.. however most of us will never quite meet the purposes criteria. We blindly purchase these items with never a thought as to what the purpose of the item is.

In my case as the engine began to heat up the thermostat would open wider and the coolant pump would have to work harder to pump more coolant to keep the temp where it should be.. So while I was grinning at the fuel I was saving from my install the coolant pump would be working harder eating up my savings.. All the while I wouldn't have a clue as to what was going on in there..

Then as the temp of the coolant began to build up in the radiator the clutch-fan would start using more power to cool the radiator...and there would go some more of my fuel!
All the while I was grinning I prolly would be using MORE fuel, caused by what I still keep thinking was a good idea.
Big JIm

You are correct in that there are pluses and minuses to any modification a person does to their vehicle. That is the nature of this game.

I do not refute that to some people there isn't enough of an overall advantage for them to believe the mod worth it to them. For some people power is not everything. With that said, you still cannot argue with the power results in the cases where UDP's are offered and able to function in a vehicle with minimal side affects.

 

[MAKG]

With that said, you still cannot argue with the power results in the cases where UDP's are offered and able to function in a vehicle with minimal side affects.

Corrected, this reads:

With that said, you still can argue with the power results in the cases where UDP's are offered and able to function in a vehicle with minimal effects.

You're screwing with REGULATED systems. It will compensate away everything, until you max it out. Once you max out the regulation, you have a substantially lower performing system than what you had to start with.

 

[rocket5979]

And whatever UDP's do "Gain" it is mostly at HIGHER rpm than "cruising"
And what's left is WHILE accelerating, what remains is tiny indeed and mostly because the people doing the testing want to believe.

I'm not saying you aren't trying to be objective in your testing
I'm saying that you are incapable of being truely objective.
and generally we all have difficulty being objective.

A true "objective" test would be having a driver other than the vehicle's
drive it both with and without UDP's and not informing them of the switch.

It is intuative that spinning the engine accessories more slowly
would reduce drag, but as I outlined above, considering all the
factors reveals that any possible effect can only be a small
fraction of what the optimistic buyers of those things want to believe.

And it's in the sellers interest to make money.

The vehicle manufacturers are scrambling and grasping at straws to save every fraction to meet CAFE and yet many believe if they could spin shit more slowly to save gas they wouldn't try it....

Anyone remember VAP/S?

Yeah, spinning your alternator more slowly might saye you something
but probably only 10% as much as folding in your side mounted Rearview mirrors above 45mph.

Or taking the crossbars off the rooftop road rack on your explorer or bronco2.

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AD,

Regardless if it is power under the curve or at peak it is still power gained. Obviously I would rather have a 5 hp average under the curve gain than a 10 hp peak only gain any day of the week. The more usable power the better. Still, power gained at peak does count for something. I believe your previous post that I quoted in my last post was inaccurate and much too general a statement.


By what personal testing or firsthand knowledge are you able to come to the conclusion to back the statements you have made here in your last two posts? If I am understanding them correctly you are more or less saying that UDP's do not net any real results??? Not only that but it also seems that you go on to say that they "cannot" net any positive power results due to the circumstances you outlined in your first post I replied to??? As a person who does one hell of allot of vehicular power modification I would have to strongly disagree if that is your position.

As a performance business owner I always do allot of testing to see gains in vehicle from various power modifications. I rarely trust another persons results because I never really know how scientific their approach was to getting their data. In my testing it is as simple as the UDP's went on and power increased. The reason that happened was because there was less parasitic loss from the other front accessories on the engine. There was power under the curve and also at peak as well. I trust my findings, which include understanding of both theory AND application versus what seems to be just theory alone. While there are power mods that are sometimes hyped a little too often by salesmen only caring about making a buck, I can say that in allot of cases UDP's are not one of them. Not all vehicles will gain the same amount of power from UDP's or any mods for that matter. You may only gain 8rwhp and 9 rwtq on a modular 4.6 from a Mustang GT but when you do UDP's on a 4.2 V6 you only gain 3rwhp before running into charging or cooling issues. Regardless of how much power happens to be gained in a given application the theory behind why and how UDP's can achieve power gains is solid.

I do not mean any disrespect by anything said in this post. I am just calling it the way I am seeing it here.

 

[rocket5979]

You're screwing with REGULATED systems. It will compensate away everything, until you max it out. Once you max out the regulation, you have a substantially lower performing system than what you had to start with.

Most any time you make a modification to a modern vehicle you mess with regulated systems. In some cases you only need to make the initial mod and will see power gains without need to recalibrate anything else or otherwise have any potential side affects. In most other cases, such as when changing to a different MAFS (for instance) to allow more air metering ability in a supercharged application you will need to recalibrate your MAF transfer table so as to ensure that fueling and load, and thus spark as well are correct. Being able modify a vehicle and also work with the stock regulating systems is part of the overall picture. That is synonymous as peas and carrots.


The computers and systems on these vehicles are smart yet very dumb systems when you really understand HOW they work together versus just what they do. Now, with some of the Canbus vehicles things have got allot more smart with more network communication oriented systems are in use; but still aren't nearly as smart as the average owner or even mechanic thinks they are.

Just out of sheer curiousity how exactly will this "regulated" system compensate everything away??? I really want to hear what you mean here.

 

[AllanD]

AD,

Regardless if it is power under the curve or at peak it is still power gained. Obviously I would rather have a 5 hp average under the curve gain than a 10 hp peak only gain any day of the week. The more usable power the better. Still, power gained at peak does count for something. I believe your previous post that I quoted in my last post was inaccurate and much too general a statement.


By what personal testing or firsthand knowledge are you able to come to the conclusion to back the statements you have made here in your last two posts? If I am understanding them correctly you are more or less saying that UDP's do not net any real results??? Not only that but it also seems that you go on to say that they "cannot" net any positive power results due to the circumstances you outlined in your first post I replied to??? As a person who does one hell of allot of vehicular power modification I would have to strongly disagree if that is your position.

As a performance business owner I always do allot of testing to see gains in vehicle from various power modifications. I rarely trust another persons results because I never really know how scientific their approach was to getting their data. In my testing it is as simple as the UDP's went on and power increased. The reason that happened was because there was less parasitic loss from the other front accessories on the engine. There was power under the curve and also at peak as well. I trust my findings, which include understanding of both theory AND application versus what seems to be just theory alone. While there are power mods that are sometimes hyped a little too often by salesmen only caring about making a buck, I can say that in allot of cases UDP's are not one of them. Not all vehicles will gain the same amount of power from UDP's or any mods for that matter. You may only gain 8rwhp and 9 rwtq on a modular 4.6 from a Mustang GT but when you do UDP's on a 4.2 V6 you only gain 3rwhp before running into charging or cooling issues. Regardless of how much power happens to be gained in a given application the theory behind why and how UDP's can achieve power gains is solid.

I do not mean any disrespect by anything said in this post. I am just calling it the way I am seeing it here.

I don't think you are being disrespectful, but I do think you are looking at the problem with too much focus, tunnel vision infact.

So while you may be calling things the way you see them I'm gonna keep telling you you need new glasses.

At the risk of further wasting my time...
IF I accept the arguement that the pullies save you 5%
at the power peak (and quite bluntly I don't) that does
NOT equate to saving 5% at cruising rpm.
at say 5000rpm the savings MIGHT be 5% but at 3000rpm it will
be at best 2.2%, and could easily be only HALF that...

That's the part you aren't getting, they don't Save "x" horsepower
they save a percentage, but that percentage varies depending on where in the rpm range you are looking

SELF REGULATING SYSTEMS tend to compensate for your
phucking around with them.

As I said above if you spin the alternator more slowly, by ANY degree the voltage regulator will simply turn up the field current as much as is necissary to maintain voltage, it can easily DOUBLE the field current while attempting to do this and since the alternator operates less efficiently at the lower rpm caused by your underdrive pullies the V-reg will turn up the field current even farther.

So in all likelihood from the standpoint of the self-regulating alternator alone you can easily wind up with a net loss.

Infact it's likiely that you could see a power gain by spinning the
alternator FASTER by installing a smaller pulley on it....
Because the alternator becomes more efficient as it's spun faster, thus field strength would be reduced...

What MAKG and I are trying to tell you is that you are basing your ASSumptions on exagerations if not outright LIES of the makers of
those pullies.
Manufacturers who make them because someone like YOU is willing to buy them.

Underdrive pullies were originally made by race teams, not to "Save power" by spinning the accessories more slowly, but to spin the accessories more slowly in race conditions to avoid blowing the accessories because they were spinning them
sometimes twice the speed they were designed for!

If you are getting better mileage with UDP's it is due to unconcious
subjective differences in your operation.

you NEED to perform a test that is not subject to driver input
concious or otherwise.

and even the best laid plans... it's likely that if you were to drive across Nebraska on cruise control both with and without the pullies that there's be some other difference that would queer your results one way or the other
(temp, traffic wind speed or direction etc)

In any even the maximum change your pullies could generate WITHOUT self regulating systems negating the effect is ~0.4mpg.

So I'll bluntly call bullshit on any greater claims right here and now.

 

[rocket5979]

I don't think you are being disrespectful, but I do think you are looking at the problem with too much focus, tunnel vision infact.

So while you may be calling things the way you see them I'm gonna keep telling you you need new glasses.

At the risk of further wasting my time...
IF I accept the arguement that the pullies save you 5%
at the power peak (and quite bluntly I don't) that does
NOT equate to saving 5% at cruising rpm.
at say 5000rpm the savings MIGHT be 5% but at 3000rpm it will
be at best 2.2%, and could easily be only HALF that...

That's the part you aren't getting, they don't Save "x" horsepower
they save a percentage, but that percentage varies depending on where in the rpm range you are looking

SELF REGULATING SYSTEMS tend to compensate for your
phucking around with them.

As I said above if you spin the alternator more slowly, by ANY degree the voltage regulator will simply turn up the field current as much as is necissary to maintain voltage, it can easily DOUBLE the field current while attempting to do this and since the alternator operates less efficiently at the lower rpm caused by your underdrive pullies the V-reg will turn up the field current even farther.

So in all likelihood from the standpoint of the self-regulating alternator alone you can easily wind up with a net loss.

Infact it's likiely that you could see a power gain by spinning the
alternator FASTER by installing a smaller pulley on it....
Because the alternator becomes more efficient as it's spun faster, thus field strength would be reduced...

What MAKG and I are trying to tell you is that you are basing your ASSumptions on exagerations if not outright LIES of the makers of
those pullies.
Manufacturers who make them because someone like YOU is willing to buy them.

Underdrive pullies were originally made by race teams, not to "Save power" by spinning the accessories more slowly, but to spin the accessories more slowly in race conditions to avoid blowing the accessories because they were spinning them
sometimes twice the speed they were designed for!

If you are getting better mileage with UDP's it is due to unconcious
subjective differences in your operation.

you NEED to perform a test that is not subject to driver input
concious or otherwise.

and even the best laid plans... it's likely that if you were to drive across Nebraska on cruise control both with and without the pullies that there's be some other difference that would queer your results one way or the other
(temp, traffic wind speed or direction etc)

In any even the maximum change your pullies could generate WITHOUT self regulating systems negating the effect is ~0.4mpg.

So I'll bluntly call bullshit on any greater claims right here and now.

Allan,

Of course your hp gains will become smaller when spinning the engine/accessories slower. Just like when you spin the engine/acc faster the hp gains will increase semi-proportionally too. That is how drag works. The nearer you get to peak power and rpm the higher the hp gains will be. The HP gain will not be as linear as most measured reduction in drag works because of the different loads the alternator places on the front serp system; but even that variable load percentage only extends up to a certain point. If someone expects that when they bolt a UDP on that they will get X amount of horsepower gain across the entire rpm range then of course they are mistaken. I do agree with you there. In fact, I do not really see where I posted anything that suggested that the horsepower gains were constant across the rpm range. All I claimed was that power is in fact able to be gained from using UDP's in vehicles without consequence (not all vehicles) and the theory as well as application behind it is solid.

If your alternator were the only accessory to be driven then your position may hold water. What you seem to fail to realize is that there are multiple accessories on modern vehicles that do allow horsepower benefit to be obtained by reducing drag encountered by turning them slower. The gain netted from driving those slower will more than make up for any potential loss seen by the AVR pulling more power, in-turn increasing the magnetic field that the rotating parts inside it see (thus increasing drag).

Did you bother to read my post or did you just skip it altogether??? Where did I ever mention that I am operating off of any sort of manufacturers data here??? I never said that. In fact if you would have read my previous post you would have realized that all the information I operate off of is personal findings from the tests I have personally done. Your tone is really bordering on the line of condescension here so I suggest you relax a little bit. You also may want to know that you are most assuredly not talking to some newb here either. Ii have been in this business a long time. The reason I own and operate a performance business dealing with high performance modification of modern domestic EFI vehicles is because I know what I am doing and do a good job of it. I operate with a full understanding of not only just theory but also the application of it as well. I test and find the gains or losses based upon them, I never go off of manufacturer ratings as they can sometimes be "generous".

You strike me as a repair mechanic. Am I right? I am a performance mechanic. As a mechanic myself I have allot of friends and acquaintances whom are repair mechanics also. I respect the job that they do but all too often I hear them talking of certain systems on cars as if they are some form of voodoo magic. I see that VERY often in the repair mechanic community. It is just the way most of you seem to either be trained or become jaded over time. As a repair mechanic you need to know how to fix the system you are working on. Some repair mechanics do generate an understanding of exactly how the systems work on these cars but that is mostly few and far between. Most turn the wrench according to the instructions off Alldata or other database, or according to how they did the job before and soak up allot of "parts" of information about how some systems work and why or why not a performance part will work in a given vehicle. The problem here is that those repair mechanics usually only get exposed to pieces of information and thus never get the full picture. It is hard to operate effectively off of a portion of the story versus the whole thing. I surmise that is why most in the end become jaded and fall into the thinking that allot of the systems on vehicles operate on some sort of crazy voodoo magic and cannot possibly be modified to operate correctly outside of factory specifications.

Some of your thinking with specific regard to proportional gains with the UDP's are spot on. Others like the "alternator voltage reg will kill all gains" talk is unfounded and just backyard theory. This is likely based upon a portion of the information needed to really understand not only how but "why" a UDP can gain power and due to the resulting increased efficiency of the front accessory system. I have personally performed the tests to see what sort of gains UDP's have gained on certain vehicles. By the way you have talked so far it seems you have not personally performed those tests. I suggest that you do some of your own tests so that you are operating off of firsthand knowledge because a portion of the statements you make are exaggerated or inaccurate.

I am finished making my point. What I have stated in this and earlier posts is not only backed by scientific theory (of which I have a firm grasp) but also by firsthand testing of UDP's in practical application. If you guys want to argue and otherwise overthink this stuff then be my guest. I might pop into this thread after a few weeks to see where this "voodoo talk" goes.

 

[evanesce69]

Forgive my ignorance at direct quotation in this forum, but rocket did say average gain under the curve... I believe this to be not absolute gain. could be nil at low rpm and greater at high rpm, I dunno. I only read the last page since it was current.

Rocket - "Regardless if it is power under the curve or at peak it is still power gained. Obviously I would rather have a 5 hp average under the curve gain than a 10 hp peak only gain any day of the week. The more usable power the better. Still, power gained at peak does count for something. I believe your previous post that I quoted in my last post was inaccurate and much too general a statement."


objective observation from a newbie..... take it with a grain of salt



on a side note... I have learned alot "listening" to the conversation that go on within these walls.....

 

[mountaineergreen]

Drove the Ranger on a trip ~380 miles one way, took a little more than a tank, got 26.4 MPG averaging 65+ MPH. Not to shabby.

 

[red2003xlt]

What is your average rpm? I'm average 2700-2900 rpm at 70mph.

I'm a big believer in cruise control.

 

[sd]

After reading this thread what I am gathering from it is that their is no way I can improve my city mileage on my 2003 3.0l Edge...correct?...underdrive wont work because of the mostly city driving I do...and an electric fan is not going to make any difference either. So I just keep my motor bone stock and no mods and pray I get a tailwind? .....if I could even just get 2-3 more mpg i'd be happy but frankly I dont see how thats going to happen......please prove me wrong on my conclusions of this thread....appreciate any info..ty

 

[Just_Randy]

I think I've said it somewhere on her before, but I'll reiterate. Air up your tires! Its free, it saves loads of gas, and it takes 2 minutes to do. I run mine at 40-45 psi when gas prices are high. If they come back down or for some reason my income skyrockets, then I let them down to 35 for comfort.

All this UDP and alternator talk had me remembering when I used to drive without an alternator altogether. I'd drive to the jobsite with a fresh battery and plug in a charger when I got there. Actually, I could make it a couple days without a charge. So, if you want better gas mileage, just disable the alternator and charge your battery on your power grid at home. Who knows if your saving money, but I agree with Allan that a bigger pulley isn't going to do anything... and it might even end up in a net loss unless you gear it so low that it doesn't function anymore (ie, your lights would dim until you got to a higher rpm). As a matter of fact, if you could find a battery that is 14.4 volts to begin with, I doubt the alternator would offer any resistence other than belt and bearing friction no matter how you geared it.

Water pumps, power steering, and AC might be a different discussion though.

Another way to save gas is not racing up to stop. 99.9% of drivers out there do this. Only big rigs drive correctly. If you race up to stop, you're not getting anywhere any faster and you're wasting gas and brakes.

And cruise control uses up gas unless you're driving on 100% flat ground. Otherwise, you should haul down hills and carry momnetum up the other side while going progressively slower to the top.... like truckers.