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yeah, this is time of 310HP car. For example my friend have Opel Vectra OPC with 310HP and we have similar times.
 

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The problem with whp is you can only compare it to other data from that same dyno sesssion. Nothing else.

Crank hp is corrected and standardized so it can be compared.

Whp on the other hand varies DRAMATICALLY from dyno to dyno and based on both programming and calibrations of dyno.

I can literally get the same dyno to spit out 200whp or 600whp on the same car on the same session.

That said the p2 is advertised as picking up over 80whp over stock. We all know thats completely ridiculous and not supported by acceleration data or data logs
Sure. whp is dependant on many factors, but it's REAL data based on those conditions.
Crank is a function of that data, modified by an algorithm which is also different from dyno to dyno. Not sure how that is more reliable than measured data...
I don't believe P2 390 hp either. But I do believe 313 whp, which is in line with what tuners around the world are being able to achieve on the 2.0.
I am curious on how you could trick a dyno 200 to 600?
 

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Dragy is best. Now as far as whp or chp they are both measured or calculated data and can easily be manipulate by many different variables im sure. I still prefer whp as i feel it is measured using wheels spinning the, thus whp. Chp introduces yet another calculation and additional room for -/+ error for driveline loss.

Now cant you correct whp as well? I swear ive seen whp measured then whp with correction factor calculated in on many a dyno sheet.
 

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Sure. whp is dependant on many factors, but it's REAL data based on those conditions.
Crank is a function of that data, modified by an algorithm which is also different from dyno to dyno. Not sure how that is more reliable than measured data...
I don't believe P2 390 hp either. But I do believe 313 whp, which is in line with what tuners around the world are being able to achieve on the 2.0.
I am curious on how you could trick a dyno 200 to 600?
Just a small correction. Tuners of 2.0 have NOT been achieving around the 313 WHP, all the reputed European tuners quote around 310 to 330 CHP, which is how it has always been traditionally since the advent of dynos here, for whatever reasons (I believe it is because auto manufacturers have always quoted power in chp and selling the tune makes more sense in chp to the average customer). Having said that any good dyno operator should be able to produce correct results if not pretty much all of them won't be getting near identical results (chp). Almost all modern dynos are inertia based for example dynojet makes, there are no simple ways to manipulate the results which helps keep results consistent if comparisons are made to a different dynojet results. The inertia variables can only be changed by the Dyno manufacturer themselves, and it is not something they do. The Dyno software offers a handful of correction factors (SAE, DIN, JIS, EEC, and Uncorrected) to compensate only for atmospheric conditions such as temperature, pressure and humidity.
Also, the dyno produces whp and converts this to chp basd on the roller resistance on the deceleration run based on approved standards of measurement set by the dyno maker, so there is an element of uniformity of standard of measurement with the caveat that the dyno operator is experienced, dyno is working correctly, there are no issues with the car and the dyno operator is not inducing an erroneous measurement intentionally or otherwise. Otherwise how are all the EU tuners reporting nearly the same crank converted measurements? One way to look at it or consider as a possible scenario is if they measure WHP incorrectly, the CHP will consequently be wrong.

The issue under contention here is ECs WHP is also significantly more than other tuners are achieving on the 2.0 engine. Not saying theirs is false, but it is significantly different to anyone else that makes some of us wonder how that has been made possible.

These guys are all well reputed and quote around 310 CHP. There are lots more.




 

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Just a small correction. Tuners of 2.0 have NOT been achieving around the 313 WHP, all the reputed European tuners quote around 310 to 330 CHP, which is how it has always been traditionally since the advent of dynos here, for whatever reasons (I believe it is because auto manufacturers have always quoted power in chp and selling the tune makes more sense in chp to the average customer). Having said that any good dyno operator should be able to produce correct results if not pretty much all of them won't be getting near identical results (chp). Almost all modern dynos are inertia based for example dynojet makes, there are no simple ways to manipulate the results which helps keep results consistent if comparisons are made to a different dynojet results. The inertia variables can only be changed by the Dyno manufacturer themselves, and it is not something they do. The Dyno software offers a handful of correction factors (SAE, DIN, JIS, EEC, and Uncorrected) to compensate only for atmospheric conditions such as temperature, pressure and humidity.
Also, the dyno produces whp and converts this to chp basd on the roller resistance on the deceleration run based on approved standards of measurement set by the dyno maker, so there is an element of uniformity of standard of measurement with the caveat that the dyno operator is experienced, dyno is working correctly, there are no issues with the car and the dyno operator is not inducing an erroneous measurement intentionally or otherwise. Otherwise how are all the EU tuners reporting nearly the same crank converted measurements? One way to look at it or consider as a possible scenario is if they measure WHP incorrectly, the CHP will consequently be wrong.

The issue under contention here is ECs WHP is also significantly more than other tuners are achieving on the 2.0 engine. Not saying theirs is false, but it is significantly different to anyone else that makes some of us wonder how that has been made possible.

These guys are all well reputed and quote around 310 CHP. There are lots more.




I see, thanks for clarifying.
 

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I see, thanks for clarifying.
No worries. You see the point right. The three tuners I have linked are independent, experienced Alfa tuners and are in 3 different countries using most likleyb3 different make of model of dynos. Yet they all report near identical results. You have then ask why and how if you see one vastly different. These engines are complex yes but there is no secret.
 

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I am curious on how you could trick a dyno 200 to 600?
Many people do it accidentally instead of on purpose. Even the dyno operatormotor trend used to dyno the c8 Corvette had to orint a retraction because they accidentally dynod it wrong


 

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Pops and bangs is a global mod, it can't be turned off.
I second that. It will even happen in A mode, but you'll have to be more deliberate about the exhaust overrun. That in itself shouldn't be a factor here.
 

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CHP on a dyno that does an inertial coast down is alot harder to manipulate than whp...

For the later all you need to do is go from low tire pressure, differential and transmission fluid temps to high pressures and hot temps - and poof you can easily see 10-15% or more whp "gain" .
 

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I dont understand, is chp measured on coast down from high rpm to low rpm? I always assumed whp is measured on the pull side and then corrections and chp calculated off the whp measurement. So if its measured on the coasting down from the pull then thats something i wasnt aware of but it explains why they always let the car coast down instead of slowing it down. 👍🏻
 

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I dont understand, is chp measured on coast down from high rpm to low rpm? I always assumed whp is measured on the pull side and then corrections and chp calculated off the whp measurement. So if its measured on the coasting down from the pull then thats something i wasnt aware of but it explains why they always let the car coast down instead of slowing it down. 👍🏻
Dynos that have that ability like a MAHA do just that. The coast down goes on for like a full minute. Much different than the coast down on a mustang. A properly run MAHA dyno provides such accuracy for chp estimates that oems and governments use them for assistance with certification

The other big issue though with trying to use wheel hp readings from dynos to give any idea of real world street power or for comparison purposes across dynos is not just the amazing variability between dyno types but also the amazing variability between dyno environments, dyno calibrations, and dyno settings.

1. Dyno types. A properly calibrated dynapak hub dyno can read 20% higher than a properly calibrated dyno dynamics dynometer. Ive seen as little as 10% drivetrain loss on an AWD audi on a dynapak and as much as 40% drivetrain loss on the same car on a dynodynamics.

2. Dyno calibration and programming- covered in the ams video. You can literally see hundreds of horsepower differences on the same car on the same dyno due to these changes in calibration and programming

3. Dyno environment- using a proper dyno chamber means the dyno is installed in a temperature controlled dyno cell that can be brought to SAE test conditions. Theyre rate and a thing of beauty. In the cell should be a turbine fan across the full frontal area of the vehicle that can simulate up to 70mph of real force winds. Very rare. You have to control for how tight the car is tied down, air pressures, fluid temps, miles on oil, and om and on. You almost never see these dyno setups.

One of the local mustang dynos i use i was doing testing and getting oddly low numbers on baseline. They use crappy home depot style fans and carpet fans like alot of shops. I moved one fan over literally 20 inches to a spot i knew was a hot spot at the front of the car and immediately picked up 30whp for my baseline just moving the fan over. That could have really screwed me up if then i did a modified run and thought i really picked up 30whp from the mod when really it was from the fan placement. Little things like this can really screw up the data

Proper...
100129


Proper... note the ceiling mounted turbine fans like those used in wind tunnels.

100130


100131
 

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Dynos that have that ability like a MAHA do just that. The coast down goes on for like a full minute. Much different than the coast down on a mustang. A properly run MAHA dyno provides such accuracy for chp estimates that oems and governments use them for assistance with certification

The other big issue though with trying to use wheel hp readings from dynos to give any idea of real world street power or for comparison purposes across dynos is not just the amazing variability between dyno types but also the amazing variability between dyno environments, dyno calibrations, and dyno settings.

1. Dyno types. A properly calibrated dynapak hub dyno can read 20% higher than a properly calibrated dyno dynamics dynometer. Ive seen as little as 10% drivetrain loss on an AWD audi on a dynapak and as much as 40% drivetrain loss on the same car on a dynodynamics.

2. Dyno calibration and programming- covered in the ams video. You can literally see hundreds of horsepower differences on the same car on the same dyno due to these changes in calibration and programming

3. Dyno environment- using a proper dyno chamber means the dyno is installed in a temperature controlled dyno cell that can be brought to SAE test conditions. Theyre rate and a thing of beauty. In the cell should be a turbine fan across the full frontal area of the vehicle that can simulate up to 70mph of real force winds. Very rare. You have to control for how tight the car is tied down, air pressures, fluid temps, miles on oil, and om and on. You almost never see these dyno setups.

One of the local mustang dynos i use i was doing testing and getting oddly low numbers on baseline. They use crappy home depot style fans and carpet fans like alot of shops. I moved one fan over literally 20 inches to a spot i knew was a hot spot at the front of the car and immediately picked up 30whp for my baseline just moving the fan over. That could have really screwed me up if then i did a modified run and thought i really picked up 30whp from the mod when really it was from the fan placement. Little things like this can really screw up the data

Proper...
View attachment 100129

Proper... note the ceiling mounted turbine fans like those used in wind tunnels.

View attachment 100130

View attachment 100131
I still fail to see how this method can provide accurate conversion from whp to chp. If left in gear during coastdown, you'd introduce significant artificial drag (compression braking) and if you switch to neutral you'd remove legitimate drivetrain losses - everything forward of the back half of the transmission. I don't see how this method can provide any useful data on the actual losses.
 

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I still fail to see how this method can provide accurate conversion from whp to chp. If left in gear during coastdown, you'd introduce significant artificial drag (compression braking) and if you switch to neutral you'd remove legitimate drivetrain losses - everything forward of the back half of the transmission. I don't see how this method can provide any useful data on the actual losses.
transmission and behind is pretty much what you need to accurately convert whp to crank power... You are accounting for transmission, differential, rolling resistance, bearings, ect
 

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transmission and behind is pretty much what you need to accurately convert whp to crank power... You are accounting for transmission, differential, rolling resistance, bearings, ect
The heavy load in the transmission comes from the front half right? Pump, torque converter, etc are all driven directly from the input shaft. Then there's the loss from flywheel crankshaft, valvetrain, and all the belt driven engine accessories that would be removed from the equation. I don't see how that could be considered remotely accurate.
 

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I still fail to see how this method can provide accurate conversion from whp to chp. If left in gear during coastdown, you'd introduce significant artificial drag (compression braking) and if you switch to neutral you'd remove legitimate drivetrain losses - everything forward of the back half of the transmission. I don't see how this method can provide any useful data on the actual losses.
I dont claim to know their fancy calculations...

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All i can say is it is extremely accurate and uses by oem like audi and bmw to certify results
 

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