we have had this discussion & your position is pretty clear . You must concede there is some difference surely MM its just how much that is questionable .
2 to 3 hp is very believable .

I concede nothing.
The butt is not a dyno.
consensus is not science.

OK - what you are saying then is that water pump + alternater + Air con draw the same power at idle as they do at 9000 rpm .......

You are daft (if you actually believe that is what I am saying).

No its not - but I just made that point to illustrate a fact .

Accessories take power to run
The higher the rpm - the more power they use
Therefore it follows that if you run them slower you use less power .

You keep saying that there is no benefit - I'm pointing out there has to be "some" benefit by virtue of the above .
I agree with you that the benefit is not great (you convinced me of that) but I know it is there all the same.

If all the accesories drew 10hp at 9000 rpm then a 20% UD pulley would release 2 hp .

The draw on the belt is not linear:
The drag on the water pump diminishes as it approaches the cavitation point.
The drag on the alternator diminishes as its output exceeds demand.
WE DON'T HAVE POWER STEERING, which is the #1 drag item on a conventional motor.

But, most importantly, these subsystems are sub-par to begin with. Any power gain you might possibly realize is negated by the potential damage resultant from diminished performance of these systems.

If you are running a full-out race car, this might not matter. But, the fact is, almost everyone that might be advocating these pullies is just ricing, not racing.

Why bother? Do you even see the ludicrousness of your statement?

yes it is pretty silly arguing over 2 hp and I agree that hp saved will not be linear . I'm just trying to get you over this idea that there will be no difference at all .

And for the record - its been 8 months running the pulley for me now with no adverse effects I'm aware of . So where you get idea of diminished performance is a mystery to me.

See I always took heed to everything you have written on this forum MM, and when I installed the pulley I truely wasn't expecting much if anything in terms of a performance gain. However we even did it again last night and the results were still the same. I'm not sitting here saying running by myself my car feels like a rocket ship now, but at the same time there was physical evidence that we proved several times. I don't know how else to prove the pulley actually did help. I'm personally convinced from this first hand expirience, whether or not that helps anyone make the decision or gives them any help isn't what I am really going for. I'm just sharing my own discoveries.

You STILL don't get it.

Whether there is a difference or not, 2 HP IS NOT WORTH THE RISK.

You can't (and it is not worth proving) until you can show a repeatable increase on a dyno that exceeds the normal statistical variation.

Once again:
Your butt is not a dyno.

then what magically happened to my car after repeated efforts to make up the distance? I am not questioning that you do or do not know your shit I am a firm believer you are much smarter than most on this forum by some amount, however what explains the sudden increased acceleration of my car? I'm shifting exactly the same. Gas was at the same levels for the last few times before this as well. I didn't gain any weight. He didn't have any passengers, neither did I. So how is it possible for me to heat with a car that was pulling on me prior to this?

And you measured this sudden increase in acceleration how, exactly? By comparing yourself in a dead heat against another car?http://www.mazdamaniac.com/portal/smiles/icon_no2.gif
Brilliant. Very scientific.

I rest my case.

See if you went so far as to READ what I had written before hand you would know this was a car that pulled consistantly PRIOR to the install and now it is a heat between our cars CONSISTANTLY. But hey, I guess if you only read what you want it's easy to be sarcastic and unjustly pretentious towards someone elses expirience. I'm not even going to bother with this one, I was giving my advice for what it's worth. Didn't claim my "butt dyno" gained anything, I didn't claim any numbers of any sort. I stated the before and after first hand expirience of 3rd and 4th gear and the effect it had. Whether or not that works into all your mathematics and theories is one thing, but I'll take first hand expirience over numbers on a page any day of the week thanks.
:rolleyes:

Charles I appreciate your response. Like I had said earlier, I also did not buy the pulley thinking I was going to be gaining power. I bought it for the 'bling' factor that was mentioned before. Another thing I'd like to point back out, we both switched cars we got the same results consistantly afterwards. We aren't talking about autocrossing or even a straight drag race, just a start from 3rd gear, a shift to 4th, then letting off before needing to shift again. Sure human error could have been a possibility, but after repeated attempts to prove otherwise we kept getting the same results. Maybe he did lose some power from something, maybe he didn't. Those variables weren't factored in because they are unknowns. Based on what we knew going in, the pulley had helped to a certain if small extent.

I was just stating how it annoyed me how he was acting so condesending towards my responses for no good reason since I never claimed anything about my butt dyno or anything of that sort. If I gained 2 hp then fantastic. I was just sharing my personal expirience and stating the conditions that were involved under these 'tests'.

Air temps? Humidity? Coolant temps? Oil temps? Consistent surface? Do you have any of that data?

Rendering your test meaningless because of the statistical variation.
Actually, if you had an even bigger gain, you would be in a deeper chasm of improbability.


I am condescending towards you because I am tired of bullshit like this. I can only knock down so much crap before it gets tiring.

Ugh. Flywheels.
Same story - it is, at best, a drivability improvement.
Though, you are talking about a fair amount of weight (several pounds vs. the ounce or two from a pulley) and a greater inertial component (several inches from the center vs. an inch or two). So, the rate of change (HP, not torque, which will stay the same) will scale microscopically.

Bring it on! I'm even more abrasive and confrontational in person because you get to see the disdain on my face, my agitation and my wild hand gesticulation.
Increased experience for all involved.

BTW - a .1 change in 1/4 mile is equal to 5 HP at 14 seconds or so on a 3100 sled. The ratio increases significantly as you shed tenths.

If you are tired of it, why not just try ignoring it since you don't agree with it? God forbid. Whatever, I stand by what I said, I like the pulley and would recommend it power gain or not.

Because you will continue to claim this crap and someone might believe you.
That would be unacceptable.

hahaha... Yep, disagreeing with you is obviously unacceptable. Not gonna even continue posting here. I don't have e-penis syndrome so I'm gonna just let it go.

Disagreeing with me is totally acceptable. Support your ideas with data.

I'm not worried about protecting you or Charles or anyone that might have some mechanical empathy.
I worry about the overall impression that the community gets when the typical 22" rim crowd starts bolting on parts based on unfounded claims and then screams bloody murder when some other subsystem fails because of their efforts and they blame in on anything but their ignorance.

E-penis syndrome. That is pretty funny. However, it is obvious that you do or you wouldn't exert such energy in defending the indefensible.

well I'll tell you what, you tell me exactly what data you want me to give you, I will run the same exact tests and let you know the results. Is that fair then?

and I actually did laugh at the 22" inch rim crowd comment. There is an rx8 here that has the italian flag painted on his front end with 20 inch chromes that tells me he runs 13'9 with just a magnaflow exhaust in the 1/4 mile.

So much angst! I can see both sides of the story on this one and generally I don't see a point in having an argument over it.

There is an inexhaustable pile of manuer that is universally fed into internet car forums through the unknowing, unintending, and unabated asshatery of "car enthusiasts". This, however, is not really the case here. Both sides have attempted to support their ideas with evidence. It's unreasonable for any small claim (such as 2 hp) to be scientifically documented by a lay person to the level required for publication. No one on here is going to ever put forth the effort required to prove beyond scientific uncertainty that X mod actually caused a meager HP gain in a car.

Pulleys of lower rotating inertia lower power required to accelerate them with engine speed just as a lighter FW, lighter drive shaft, light wheels, or any number of other rotating component. Depending on your frame of reference, you could say more power exists at the wheels or less power is used in the drivetrain. Accelerating these components uses tq and hp as hp is merely a multiplicative quantity of tq.

Pulleys (underdriven) also lower the rotational speed of accessories. Whether this decreases the amount of torque/hp they absorb is entirely debatable. The alternator (electrical) and the water pump (fluids) do not depend on simple motion mechanics to calculate the power draw. I don't see anyone about to flow test the water pump or map the amp/torque performance of the alternator. That is, in my opinion, beyond what I would expect from a public car forum.

I think the simplistic roadtest is a nice "indication" if not a proof that the pulleys have some positive performance enhancing effect under those conditions. It would be equally difficult to prove that they don't. I don't think the forum needs to be defended so earnestly in an effort to protect the uninformed from making a purchase in the hopes of magical power gains beyond reason. I say, if you are going to spend your money on car parts without knowing the dynamics under which they work, well, a fool and his money are soon parted.

In short, thumbs up to an actual effort to prove something. Thumbs up to nice looking pulleys. And.......I'm personally not going to buy them, but thumbs up to someone who decided to support the 8 community and make them.

well said maxx .

SE3P - I know a test that would prove "beyond reasonable doubt" that the pulley got the gains you experienced .
Put the stock pulley back on and repeat your test - then put the AP on again and do the test again on the same day.
That combined with the testing you have already done would pretty much eliminate all variables . If you have the time & energy to do it - it would be great info .

I have a totally open day next thursday, I'll see if my friend is down for the expiriment as well. I guess that would prove it, right?

^^ And verify the identical variables as noted in my post #68. Exact.

Even then, all it shows is a correlation. It isn't proof, but is a reasonable conclusion.

Really, you should perform the test against another identical car, with and without.

Air temps, Humidity, Coolant temps, Oil temps, Consistent surface. Alright, I can get those for this test. I only wish I knew someone with an 06 base or any year for that matter base in stock form.... I agree that would be the best measurement for any improvement. I'm just working with what I have available to me.

coolant temp is probably the one you need to most wary of . Testing I've done suggests that this makes quite a difference .
If you both take it easy before the runs and cruise together for a minute or so then coolant temps should be close enough .