330 hp, and how did you meausre this? if it was at the wheels, your car had more than the manufacturer advertised..... you know why right? there are drive train losses. (efficiency of the drive line components, like the transmission and differential). usually, with modern cars, the loss is about 15% including the rolling losses of the tires on the measuring rolling (which is near 5%) at the max HP range. max torque range, the losses are a little less. most do NOT understand these facts.

 

the dyno loads have NOTHING to do with the results. all dynos are calibrated . the most simple is a rolling dyno with the large, heavy inertial drums. you spin them up at a rate, that gives the HP. there is no diffeence between dynos . Now, there is a difference between how the car is attached to the dyno. (strap down force adding friction) and there are certainly differences in the air density , (temp, pressure and humidity) as welll as intake air flow (do you use a large fan, etc?)

i go to the dyno 2 times a year just to check on the engine, and it always is within about 5 hp of each other on any of the same style rolling dynos. still witin 5 hp on a brake dyno as well.

yes, on the same dyno , same day, there still can be differences. But, different dynos can measure your cars engine power differently. the dynos should be accurate and again, has nothing to do with the load. power measured is power measured , period. you can see if the correction factor is correct. that can be a variable, But actual results are actual results. HP is a rate of doing work. you accelerate that drum at a rate, and that's the HP you get, just as if you got timed in the quarter mile and someone got time segments along the way. HP can be derived from that. the brake dynos do something a little different, but they are all calibrated. However, some induce heat into the engine because of the test techique . Some folks on the rolling dynos use different gears. (4-5th should be used because it reduces a chance for traction slip, and allows the ecu to stabilize mixtures and timing better and makes the runs more repeatable when the run on the dyno is allowed to take more time (slower acceleration rates)

 

Hey I just emailed Phillip at euro charged and said there was no need for a reflash on the tune with addition of 200 cel cats?

 

I think he means when he gave a view on wheel weight and you politely but comprehensively corrected him.

This has happened before, when shown to be wrong, most of us would thank the other person for the additional information, and see it as critical to the way that discussions progress, then absorb the new information.

We have someone here that handles those occasions in a different way, and becomes rude and aggressive. We may see another example soon

 

Thanks... I guess your right. I absolutely agree about being corrected though.. heck, its how we learn. I dont think he has been very rude, but sometimes folks really believe all the BS they hear on the internet or at the car shops, and usually, they are way off base too. (trying to debunk the myths, they create myths of their own. )

anyway, I hope the information helps... does put things in perspective though. At least for me it does and it helps turn the best lap times at the track too!

 

Seriously, the argument about load types is like saying that some torque wrenches notoriously read higher than others. LOL. Any torque wrench worth a hill of beans should be calibrated to give exact and repeatable results to a known universal standard. The same applies to a dyno or any other measurement device.

I'm off to measure some lumber using my Craftsman measuring tape. They notoriously give larger measurements, so the shed I build will be bigger using the same size lumber...

 

Love to see some common sense here, WITH a sense of humor! exactly right again. the dyno is often the scape goat to make the ego feel better when things are not going so well in ECU-land.


make sure the torque wrench has a hex socket, not a metwrench socket as you then have to use the metric/English to Spanglish conversion factor to get the real torque in newton-feet .

 

It's not "necessary" but is always recommended as you are getting more airflow through the engine to help maximize the gains. It won't be huge, but you can pick up another 3-5 extra hp with a retune after mods such as high flow cats & headers etc where the change in volume & velocity of air has increase

 

Load has everything to do with dynos! If you think you will get the same numbers from a dynojet and dyno dynamics the. You clearly don't know anything about dynos. Load is everything. It not only affects the baseline but it also agree how mod improvements are also measured depending on the type of the modification.

 

007, if you get different HP numbers from different dynos it just means that either one or both brands aren't calibrated properly. It's like saying that you always weigh more on a bathroom scale that uses a spring than one using counter-weights. A pound is a pound and you weigh the same no matter what scale type you weigh yourself with. If the reading varies, then one or both scales need calibrating (or thrown away).

Yes, it's ok to use the same scale for every measurement as a guide to determine variation from one reading to another. But if you can't trust a single reading to be accurate, then the difference between values from the same a scale is also wrong.

The problem is that it's a lot easier for the average individual to determine the accuracy of a bathroom scale than it is to determine the accuracy of a dyno. So if one brand of dyno notoriously gives higher HP figures than another, how do you prove which one (if any) is right?

Load has nothing to do with it anymore than spring vs. counter-weight has anything to do with measuring your weight on the scale. The difference in readings is not because of the method of measurement but rather due to lack of calibration. I don't need to know anything about dynos to make this statement with 100% verifiable scientific certainty. I just need to know about how test and measurement devices work which, coincidentally, is what I do for a living.

 

Load is not everything and you are really pointing to your knowledge of how a dyno works, as being extremely limited. I don't know if this is true, as we are having a discussion here, but your statements that one dyno showing 25% efficiency losses compared to a dynojet or other dyno that shows near 15%, shows that you might not have a handle on the concepts/physics or technology. explain how you have determined how "load" can make this much of a difference.


yes, there can be differneces on how the engine performance is measured, but those differences should be subtle, unless you are doing chassis dyno tests that would show different results based on testing techniques. what I mean by that, how the test is conducted, and this includes things like the gear ratios the tests are conducted in. the load can be a factor too, in the sense that a lighter load can allow the car drivetrain/engine to accelerate the load at an unrealistic rate, that could allow the inertial values to be more of a factor than reality.
Also , as I mentioned before , how the engine torque or acceleration rates are measured. (e.g. are you holding rpm constant and getting measurements, and then jumping to the next higher RPM level? or are you applying a constant load and measuring pure acceleration / per unit time value? ) These factors will allow external factors to be change power output measured. However, Chassis dynos by design, try to simulate how the engine/chassis packages will be used on a track or really, how the weight (mass) of the chassis will be accelerated on the road.


bottom line, dynos measure power, almost directly! rate of change of kinetic energy is , by definition, POWER! you accelerate the rollers of known mass and size, at a certain rate, that equals power, EXACTY and is extremely easy to calculate and for a computerized system with optical speed inputs, to determine and measure very accurately! a brake dyno, or a dyno with smaller rollers, etc, also measure torque, or acceleration rates, and the car drives those devices and HP is calculated. also, more often than not, very accurate.... the only variables are test conditions ( what gear you are in, strap down forces, friction differences, etc) and correction factors, which you can elect to use or not.
so, if you think that one dyno measures power and is 50% off another dyno, you better dig a little deeper as of why.

Ive done a tremendous amount of dyno work. ive debunked , and proved a lot of HP gainers and losers. one thing that was most interesting, was going directly from the dynojet to a mustang dyno in the same day. results were very close and it was on a car with almost identical HP to the Vantage. (i.e. 320rwhp) both dynos were within about 5 hp of each other and the runs on each dyno were within about 2hp.


So, if you think one dyno "load" is different and causes some kind of measurement abnormality, lets hear about your theory of why.


I showed you in detail, why wheel and tire weight has a HP effect of 2:1 not 4 or 10:1 as some folks think. These are relatively simple equations to provide proof. same thing works on the dyno.


To summarize, and use an example of why the "load" makes little or no difference......... if put a car on rollers of 3000lbs vs 6000lbs, if we know the mass and diameters, we can easily measure the rates of acceleration as the car accelerates the drums....... this "rate of change of kinetic energy" is by definition, HP. it doesn't matter if the drum is the diameter of the earth or of a tootsie roll. (as long as you have positive traction)
same goes for a water brake dyno or a BEMF dyno. both would have been calibrated to determine what force it takes to give the pressure or voltage output. That force, at any RPM easily determines power and would correlate to the acceleration rate at that same speed (RPM) on a rolling inertial dyno.


So, yes, I do understand how dynos work, but if what I say is in anyway, incorrect, I certainly would like to know about it. I would never want to propagate any "bad" information here. so, please correct me if you have any information to the contrary.

 

usually the MAF has the ability to determine there are more air molecules passing through it and match with the appropriate amount of fuel, unless at WOT the ECU system has gone strictly open loop, which is usually the situation. this is not to say that you can get more gains by optimizing the mixture and timing in the ECU , but this is true with or with out high flow cats or headers, or any other type of intake or head mods that increases air flow to the engine .

 

The question was about the need for a reflash, not a retune. Agreed a retune should release additional hp, but simply loading the same config onto the car (a reflash) won't make any difference.

I think the way that Eurotune distribute the upgrade is that everyone with this tune gets the same config that was optimised for a single car. The greater the deviation of the target car from that original, the less well adapted this tune will be.

That is why a bespoke tune for your car will always be better than a generic tune.

 

There is a lot of very intelligent discussion going on in this thread I started here. I FEEL a great deal more power and torque since bringing my car to Eurocharged. Before getting the ECU reprogrammed I think the car ran great. As have my mechanics. So why would my original HP of engine and Whp read so low and than after the ECU charge read so much different on the very same machine, If I didn't get the gains reported?

 

I don't think anyone is suggesting you won't have achieved the gains you've seen, the debate seems to be about whether one type of dyno is inherently inaccurate. The view is that any inaccuracy is because the thing isn't calibrated correctly.

If you're seeing a before/after improvement on the same dyno, then you can be fairly confident that you've actually got that additional hp.

You should just sit back and enjoy the discussion without worrying about its relevance to your car