Dynojet's number are NOT real and 20% HIGHER Options

[Wolf_tm]

Presure2,

I report publicly your PM:

presure2 wrote:

wolf,
i deleted your post in the dyno registry.
if you dont have a dyno sheet to include, do not post in there.

I wrote in your dyno registry thread because, if you/we want to make a SERIOUS thread, we HAVE all to talk about apples... not apples and oranges.

So we HAVE to specify if our cars were dynoed on a Dynojet's dyno, because these dynos gives 20% higher than real numbers,
and if we want to compare those numbers to the REAL hp, given by the other dyno machines, we HAVE to take away a 20% from Dynojet's numbers.

MOREOVER, we all shoud speak only about SAE CORRECTED, because ambient temperature and atmospheric pressure change A LOT the power output of the SAME engine, so the SAE correction ( that normalizes all the values to 20 deg C. and 1012 millibar ) is necessary if we want to compare numbers picked up in different situation.

Are you saying were not important things to add in the dyno registry thread ?

When I go to the fruiterer and I buy 1 kg of apple, I WANT 1 kg of apple, NOT 0.8 kg because the fruiterer's scales is corrupt .... and 1 kg weighs the SAME ALL OVER THE WORLD because the kilogram, LIKE ANY OTHER UNIT OF MEASUREMENT, are fixed universally.

So Dynojet's dynos are not legally in order, because they give hp's values 20% higher from real.

Do we have to hide this thruth only because you enjoy talk with your friend, or make a signature, about your 235 whp car ?
I'm sorry, but if you dynoed it on a Dynojet, it would be better if you start talking about 190 WHP car.

presure2 wrote:

if you'd like to debate the diffrences between dynojets and other dynos, feel free to start a new thread, and ill post my stock dyno charts to refute your claim.
( i made 115whp in stock form with a 5sfe, almost exactly in line with toyotas listed flywheel #s.)

It seems to me that you DON'T want to understand:
your dyno charts means nothing.

ANYONE in the world that works in this sector, knows that Dynojet's numbers are UNREAL:
every engine engineer, every serious tuner, every serious mechanic, every people that had dynoed a car on different dynos found out that Dynojet's readings are 20% higher !

As I already reported, the dynojet's maker himself WAS OBLIGED TO ADMIT IT... because it was a valutation error EVIDENT TO ANYONE !

David Buschur,
tired of this ANNOYING fact, and you can imagine, given that he his a big and good tuner, that he was tired... because he had to explain to EVERY customers of him that the cars he makes, have not LESS hp than the competitors' ones.... are simply dynoed on a dyno that reads correctly the horsepower...
said:


" We all just need to be clear that Dynojet numbers ARE NOT ACTUAL WHP NUMBERS. If anything the numbers a Dynojet spits out are more closely related to flywheel numbers.

Before anyone opens their mouth to argue the point, the inventor, designer, originator of the Dynojet openly stated this a few months back in 3 major automotive magazines. I actually quoted what he had to say here.
__________________
David Buschur
www.buschurracing.com "


It is not enough if it was the "inventor, designer, originator of the Dynojet" to state this ???


Please.... let's talk about REAL NUMBERS... like in every other forum are already doing !
Only here, we still not specify what was the dyno, and that is definitely not serious.

Anywhere else, when talking about dyno numbers, they ALWAYS specify when " DJ " numbers.


Simply have a look HERE: http://forums.evolutionm.net/showthread.php?t=210073

" hmmm, this is an interesting thread. There are some more things to define though....such as the dyno that was used, that will make a huge difference in dyno numbers. "

" For consistency, people should be quoting SAE correct numbers. "

It's only one of the thousands thread in which they are talking about power numbers, and EVERYONE knows about the crazy Dynojet readings.


OBVIOUSLY, when we are saying that Dynojet's are 20% higher than real, we are ALWAYS talking about SAE corrected numbers, the only numbers that you can compare.

Otherwise, if we still want to talk in the way it was done till now, with the same INACCURACY and SUPERFICIALITY, no problem... this is what we will getting back from this forum.

Bye.

PS: I think I tell all the members ALL it was needed for them to understand things that are clear to anyone, if you still won't... problem is yours and I'll not add ANY reply to this CLEAR post.

[presure2]

wolf, unfortunatly for you, here in the USA, the dynojet is the #1 dyno.
they are the most consistant.
and like i said to you in my PM, my stock 5sfe proves my point.
the reason i deleted your post, like i said in my PM to you, is because that thread is for posting dyno sheets only, not to compare which dyno is better, or who has the higher #s, or to argue about how this dyno reads diffrently than another.
also, furthermore,
you clearly do not understand how the SAE method works.
SAE is for people who are above sealevel, so that you get consistant readings VS someone who is at sealevel, and other ambient temp factors.
its pretty obvious to me, by looking at the dyno sheets listed, since it SAYS dynojet right at the top of each dynosheet in our registry, who uses dynojets, and who uses whatever else is available.

my 5s made 115whp. by your theory, take 20% off that...that would be under 100whp...you telling me that the 5s, that is rated @ 135hp from the factory puts LESS that 100whp down?
your figures make no sense in the real world testing i have done.
and one more thing.
MR2OC and the one of the most respected 3sgte tuners in the whole USA uses STD correction, unless he is @ altitude.
ill side with him, over you across the pond anyday, just cause bryan would be the guy that would tune my car if ever i were in that situation.
::edit::
i just realized that you call into question my dyno ....
you can question it all you'd like.... i have no need for a pissing contest with you, and for the record that is NOT what our dyno registry is about.

[alltracman78]

:WOOT!:

[devilsden97]

WTF?

[lagos]

wolf ... here is my take on this....

at lot of things can have an affect on the dyno numbers you reach. the weather, time of day, where you live, type of dyno, etc... i can go on the best dyno in the world, and make more power because i went in the winter time, while somone with the same mods went in 110F weather.

saying that dynojet gives you "20% more" .... where does this % number come from? ive seen just as many arguments about mustang or dynodynamics dynos made by other people.

lets face it. there is no one gold standard that gives you perfect numbers. one dyno will give you more power then another one. what one is the right one? who knows! the important thing to remember is that if you want to compare 2 cars, then make sure they were on the same type of dyno, and also done with the same weather conditions.

[JoKeRkId613]

that sounds like a fight where i come from...

wolf, why are you complaining? u have a gt4. lol.

[Wolf_tm]

you clearly do not understand how the SAE method works.
SAE is for people who are above sealevel, so that you get consistant readings VS someone who is at sealevel, and other ambient temp factors.

Funny....

And WHAT do you think it's going to change with altitude.... if not the weight/height of the air's column you have over your head ? Also called atmospheric pressure ?!?

Problem is that the quantity of oxygen, in a fixed volume, not only changes with atmospheric pressure, but EVEN with the air temperature, that affects very much the oxygen density.

Correction based simply on altitude are, then, NOT ENOUGH, because at the same altitude you could have, based on weather variations, different atmospheric pressure and different ambient temperature:

I'd like to remember to everyone that we are going to have a 2.5-3% of power gain every 10 deg C. less.

That's why SAE correction ( that I " clearly do not understand how works " ) normalizes the power output to standard values according to ambient temp and atmospheric pressure ( as I already wrote in the first message )

i just realized that you call into question my dyno ....
you can question it all you'd like.... i have no need for a pissing contest with you, and for the record that is NOT what our dyno registry is about.

I didn't call into question YOUR dyno, or your " 235 DJ whp " signature, I called into question EVERY Dynojet dyno because it reads UNREAL hps.

So if we start to talk seriously of tech things and numbers, like it's on many other forums, we have to know this.


PLEASE READ ANYONE - Thank you.


David Buschur ( www.buschurracing.com ):

" I get this months Hot Rod magazine in the mail. There is an article in it, "The Truth Meter". It's about the Mark Dobeck, the originator of the Dynoet. Basics of the story is he was just building kits to re-jet carbs back in the 1980's. He needed a way to hook a large piece of equipment to a motorcycle and test AFR's and such. Well since that was impossible he decided to make a portable roller to run the motorcycles on to use his test equipment. He then got an idea to make this portable roller calculate HP.

At the time the most powerful motorcycle being built was a V Max. Here is the story from there, just a paragraph:

"Dynojets final number-fudge was arbitrarily based on a number from the most powerful road-going motorcycle of the time, the '85 1,200 cc Yamaha V Max. The VMax had 145 advertised factroy hosepower, which was far above the raw 90 hp number spit out by the formula. " (*not a quote->they are talking about the formula that they came up with to figure out the hp based on the time it took to accelerate the rolls of the dyno they built) "Meanwhile, existing aftermarket torque-cell engine dynamometers delivered numbers that clustered around 120. Always a pragmatist, Dobeck finally ordered his Chief Engineer to doctor the math so tha the Dynojet 100 measured 120 hp for a stock VMax. And that was that: For once and forever, the power of everything else in the world would be relative to the '85 Ymaha VMax and a fudged imaginary number."

Anyway, the proof is in the story about what I was thinking lately. Pick up the March 2006 issue of Hot Rod and read for yourself.

The Dynojet numbers mean basically nothing. It is a tuning tool to make baseline runs from and measure you gains. The actual numbers are inflated and that is FACT based on the inventor himself. "


++++++++++++


" Actually, from the man that designed the Dynojet, I am going to say the Dynojet reads too high.

If you consider the fact that our Mustang Dyno reads 22% lower than Switzer's AWD Dynojet then I would have to say the power that our MD sees to the wheels is pretty darn close.

( PS - Wolf's note:
he assume that its MD readings at the wheels are correct because all the hundreds dynos OF STOCK EVOS he made he is always getting the correct values provided by the manufacturer )

Consider AWD, transfer case, huge rotors, four axles, 4 tires/wheels, transmission, driveshaft etc., that could easily account for 22% loss to the wheels.

The point of this was to point out what the designer himself just put out there for information.

David Buschur
www.buschurracing.com "

++++++++++++++++++++


More clear now ?

"The Dynojet numbers mean basically nothing. It is a tuning tool to make baseline runs from and measure you gains."

So, and I take your signature as an example, to write " 235 whp", if it was dynoed on a Dynojet, has no sense.

And this is NOT a fight against ANYONE, it's simply a fight for the thruth and common knowledge.

This post has been edited by Wolf_tm: Aug 13, 2006 - 3:58 AM

[presure2]

wolf, there are a few real world facts that you are refusing to realize.
a 100% stock celica makes 135 flywheel hp.
on the dynojet i use, i made 114whp. with an injen short ram intake.
do the math.
looks like just about a 15% loss to me.
which would be spot on, IMO.

to me, that looks pretty acceptable.

[brianforster]

i wish there was just one dyno that everybody used

[brianforster]

i used to be a big drag strip guy, meaning that a pass was the only way to prove your car is fast.

then i switched to dyno numbers being a better bragging right than a low pass, but you know what, after this thread and reading some other threads, i now really dont care about dyno numbers because they can be so scattered and all they really are is a pissing contest.

from now on im not gonna think anybodys car is fast till they post a timeslip

[bloodrain]

I say get dyno'ed on 5 different dyno's, add up the total power and divide by 5, that would be you the closest real number. lol. And with the statement from Buschar, he really does know what he is talking about, but then the fact comes into play that he is mainly refering to AWD dyno's hence the fact he does performace stuff for Evo's. I dunno, to me this is a pointless arguement and like I said the only numbers I would 'really' believe would be my average theory.

[pure_dx]

where is this dyno registry in 6gc.net that you speak of? i'd like to take a look

[Fastbird]

Woooo...............ok.

Dynojet's are typically accepted as the industry standard because for a very long time, that's all that was out there. As of the recent few years though, other companies have come up with more accurate means of testing a vehicles output based on the same theory of the dynojet. Does this mean that dynojet's are inaccurate?? Not at all. Dyno numbers are nothing more than a theoretical means of putting a real world value on an estimation of a vehicles power output. Horsepower is nothing more than a derivitave of an equation spurned from torque output, so in essence Horsepower is a fake number to begin with. Dyno's are nothing more than a wonderful tuning tool.

Sure, it's fun to dyno race and compare numbers, but comparing ANY two dyno's numbers to each other is like comparing apples to oranges. The ONLY way to make accurate comparisons would be different vehicles, same dyno, same operator, same day. You want to see how much power your car is making?? Take it to the track and ignore everything but your trap speed. There you go.

Frankly, I agree with Pressure2 deleting the post in the dyno chart thread. It was specifically stated that it's for setups and dyno charts ONLY, and if you DON'T have a dyno chart then DO NOT post. Plain and simple. You want to go on about dyno's, this seems to be the thread to do it.

Wolf, where are you comig up with this standard 20% overcorrection that you're rambling on about??? I'd say if I saw I dynojet that was off by 20% the first thing I'd do is have a look at the computer settings because they should NOT be that far off. Between a dynojet and a mustang dyno I've seen variances of 3-5% HP and 5-10% TQ, that's about it. Dynojet's calibrations can be fudged just as easily as any other dyno, so if you're working on an inaccurate one check that first and foremost rather than blanketing ALL Dynojets as 20% higher than real. But......

What is a realistic dyno number??? To accurately measure the output of ANY specific vehicle, you need to be able to make the dyno treat the car like it's on the road. Vehicle weight, frontal surface area for wind resistance and drag coefficient, gearing for torque multiplication all must be taken into account. If you want the most accurate number you can find, take the car out and road tune it to max extent, the put the car on a dyno without making any changes (and see how far off the dyno says your AFR is lol). This, no matter what the number, will be an accurate baseline because your car will be PROPERLY tuned for all of it's own factors and whatever the number may be, it will be accurate for that cars baseline. That's all.

[recycle]

its a long topic... only read the main points here... but i know for sure that in japan they dyno their cars and the result is 20% more than they really are. so my stock beams ss2 that is supposed to be 200 flywheel bhp its barely 180 (with the 20% difference) 173.7 corrected value. (dyno sheet below). there are many ways to measure power but always before and after the hp there is the measuring unit 200 DIN hp for beams and i beleave this is the right way to show it.
the only standar in power mesurment is ps (1ps is the force needed to lift 1 kilo 1 metre high... dont confuse it with torque)


This post has been edited by recycle: Aug 14, 2006 - 11:43 AM

[bufferdan]

And this is why im not wasting money to dyno my car again!

Numbers mean nothing...i made like 216whp on a dyno and ran a 12.9 with my mr2...hahaha. What kinda sense is that?