dynapack dyno of my legacy 2004

True as thet say regarding RR figures being inaccurate!
The RR at AI said my car only had 386bhp, I know it had well over a million bhp! :mooner:
And it's going to have a billion bhp after mapping next weekend regardless of what the rollers say :icon_grin:
Dan
 
[quote author=Dagnut link=topic=11703.msg140517#msg140517 date=1231043862]
Actually that type of dyno is more accurate than martins as there are no losses through the wheels or tyres...I can vouch for the accuracy of that dyno we had a dyno day with our vzrs a few years back and all the figures where around 170-173..the car is quoted @ 173 on standard fuel..this 102 octane lark as well that people are going on about..it 100 octane the cars are rated on.. if he was running 99 it would be able to adjust with knocking timing...plus he has already said the car is running 1.07 bar of boost which is above standard with sti exhaust..i cants ee why it shouldn't be making an extra 10 or so bhp.
It is a fact that the dyno pak is more accurate than a rolling road..whether Robbie is the most honest regarding the figures after he has carried out work ..i dont know i wont debate that but echo had no work done no reason to lie to him..I love the fact that people are speculating your power figure based on a calculation they seem to be making regarding octane ratings for fuel.
plenty of cars came out of japan dynoing above there factory quoted figure go look it up..standard type r's have made 290...gtr's..gto's.. supras..they where all sticking to the gentlemans agreement of 280ps.
Might seem hypocritical of me as i was questioning the a1 rr figures but they where way off....I don't think its unreasonable to assume a car running extra boost and exhaust could run an extra 15bhp.
I'm not defending that nob in tdp either just so we know..the lad has 290 proven from THE most accurate way of measuring the flywheel power that we know..I don't think any of us here have the knowledge to doubt..fair play echo good figures...but the ones at the hub are the ones that count
[/quote]

Its true that the hubs are more accurate that the rollers but I did say that as far as rollers go Westward Engineering imo is the most accurate. I based this on being as many RR days there over the years and getting the impression from Martin Tracey that he simply doesn't care what the figures you think your car will make. He just gives you the printout and that's the real figure, take it or leave it unlike other places which seem to give massive figures and send you home happy. Martin also had standard 1.6and 2.0 N/A imprezas on his rollers and they gave readings within 2-3 bhp of factory outputs.

The most important thing about RR's is setting them up properly so a hub dyno badly set up will be less accurate than a properly set up roller dyno Also the results can be enhanced by setting up the dyno to reduce frictional losses giving a higher output.

A full exhaust system will raise boost pressure by about .1 bar so its possible the system fitted to this car has yielded an increase in boost and accordingly bhp. There might also be a high flow panel filter fitter which would release a few more ponies. Finally E5 (which I dont believe is the full 99 octane no matter what the stickers say more like 97) will give more power again but whether TDP's bhp figures are accurate is debateable. Without knowing the cars true state of tune its impossible to say but even if the figures were out by 10 bhp so what? The cars a stunner and no one would be able to feel a 10bhp difference from the seat of their pants anyway.

BTW the most accurate way of measuring bhp is neither a hub nor roller dyno. Its a bench dyno but you wont see one of these outside of the factory or motorsport!

Frawls
 
Sure it's all just pub talk anyway!
You can have a 330 bhp car beat a 380bhp car in drag race, or on track,
Dyno figures are grand for giving a general idea as to the car possible potential, not something to be serious about!
I think the best way to gauge a cars real world performance would be to do a street start quarter mile drag race!
ie. Cars start rolling along in first gear at tick over with foot off the clutch and then when crossing the start line, plant it,
It would take away the violent launch at the start, which greatly affects drag strip times, I know a lad who was something like .5 of a second quicker in the same car even though there was a bit of a weight disadvantage!
Dan
 
There seems to be a lot of bedroom tuners here who think they know it all.

First of all, at Trackday Performance, we operate a Dynapack 8000 evolution series chassis dynamometer in a custom built dyno cell. This 4wd system can operate as a 2wd or 4wd system and handle from 30 bhp to 2400 bhp at the hubs. We do not use a rolling road.

Secondly, all the tests were performed in front of a large crowd of spectators and results were shown live on a TV.

There is absolutely NO WAY Dynapack software can/will allow you to adjust the power/torque figures. It's impossible, so you may forget that idea.

Many of the stock cars we tested on the dyno day made less than factory power.


To clear a few things up and hopefully educate some know-it-alls....
What is Dynapack
Dynapack™ chassis dynamometers are such a radical departure from the stereotypical roller dyno that it really is in a class of its own.
Dynapack™ allows you to quickly and accurately measure engine, drive line and other performance data, with previously unseen sensitivity.
Dynapack™ attaches directly to the axle(s), thereby overcoming all the disadvantages of tyre distortion including noise, torque steer, loss of traction, tyre heat and design variations in the tyre.
•  Precise engine results - no inertia to mask faults
•  Repeatable - accurate back to back runs within 0.1%
•  Portability - on and off site
•  Stress free - 2 to 30 sec. runs for all data types.
•  Minimal noise level - no tyre interface
•  Virtually no installation and running costs
•  Cost effective - chassis and engine dyno capable
•  Flexible, easy to use software

Dynapack controls the car - Not the other way around

How is Dynapack different to a rolling road?
The first and most obvious difference is the elimination of the tyre to roller interface on a traditional roller dyno. The Dynapack™ eliminates this variable by using a variable fit hub adapter that provides direct coupling to our power absorption units. There can be no tyre slip, no rolling resistance, and no chance of the vehicle separating from the dynamometer at high speeds. Notice that we call this a variable. Tyre temperature, tyre pressure, tyre traction, etc. are all variables that can change not only from run to run, but during the run as well.



Also, axle torque and BHP figures are figures are accurate to within +/- 0.1 %. Calculated Flywheel Torque (left side) and Flywheel BHP (right side) are calculated from the axle torque/BHP results. These figures are for reference only are are accurate to +/- 5%, which Karl and everyone else on the day was told on numerous occasions! AND it says on the back of the sheets!


Regards,
Cathy
 
[quote author=subadude link=topic=11703.msg141239#msg141239 date=1231263123]
welcome to the site
[/quote]

Thanks :xmas_cheers:
 
[quote author=TDP.ie link=topic=11703.msg141247#msg141247 date=1231263639]
[quote author=subadude link=topic=11703.msg141239#msg141239 date=1231263123]
welcome to the site
[/quote]

Thanks :xmas_cheers:
[/quote]

Welcome along cathy, I was defending the dyno pak there is no more accurate way of measuring power @ the hubs in Ireland I don't think anyone can dispute that. But where the variable lies regarding flywheel power is the transmission losses..the flywheel power figure is still calculated using an estimated percentage loss..so this can be a variable in the flywheel power as this is entered by the operator and obviously leaves room for error.
I'm not saying tdp's figures are not correct imo it is very accurate as I witnessed it myself but flywheel figures can be wrong as the only accurate way to measure flywheel power is an engine dyno as you know.
you here anything from 19%-25% for Subaru but I'm sure Robbie got the quoted figure from subaru..when we where down there he had an official document from Nissan japan giving the transmission losses for the VZR
 
maybe next ISDC dyno session should be in TDP :dance: Trying to organise one for the Tezzaworld lads, if we have any spaces to spare for a few Scooby's I'll post it up here :subaru:
 
[quote author=Dagnut link=topic=11703.msg141252#msg141252 date=1231265506]
[quote author=TDP.ie link=topic=11703.msg141247#msg141247 date=1231263639]
[quote author=subadude link=topic=11703.msg141239#msg141239 date=1231263123]
welcome to the site
[/quote]

Thanks :xmas_cheers:
[/quote]

Welcome along cathy, I was defending the dyno pak there is no more accurate way of measuring power @ the hubs in Ireland I don't think anyone can dispute that. But where the variable lies regarding flywheel power is the transmission losses..the flywheel power figure is still calculated using an estimated percentage loss..so this can be a variable in the flywheel power as this is entered by the operator and obviously leaves room for error.
I'm not saying tdp's figures are not correct imo it is very accurate as I witnessed it myself but flywheel figures can be wrong as the only accurate way to measure flywheel power is an engine dyno as you know.
you here anything from 19%-25% for Subaru but I'm sure Robbie got the quoted figure from subaru..when we where down there he had an official document from Nissan japan giving the transmission losses for the VZR

[/quote]

Thanks for the welcome. That's a valid point. We did stress that point to everyone on the day. Flywheel bhp/torque is accurate to +/- 5% whereas axle bhp/torque is accurate to 0.1%.
 
[quote author=Altezza-Dan link=topic=11703.msg141257#msg141257 date=1231266001]
maybe next ISDC dyno session should be in TDP :dance: Trying to organise one for the Tezzaworld lads, if we have any spaces to spare for a few Scooby's I'll post it up here :subaru:
[/quote]

We'd be more than happy to have you guys up for a dyno day. If you're interested in arranging one then e-mail me: CathyTDP@gmail.com

I think you should check that the tezzaworld lads would be okay with offering spaces on their dyno day to other clubs....just in case!
 
we can use the Subaru's as standby cars since if some of the altezza lads pull we don't want to have to cancel the day if we can't make up the numbers!
 
@Cathy.....Didn't TDP use a rolling road dyno before the hub dyno for rolling road days? If so that would mean that TDP outputs using the roller dyno were far less accurate than those using your new hub dyno as there were far more variables to contend with.

No one has argued that a hub dyno is less accurate than a rolling road dyno all things being equal. Obviously the closer the measurements are taken to the flywheel by their very nature the more accurate they should be. This is why a bench dyno aka engine dyno is more accurate than a hub dyno which in turn is more accurate than a rolling road dyno.

What is less obvious is the accuracy of the estimated flywheel power and torque which rely on the operator inputting the correct figures for transmission losses. If too high a transmission loss figure is inputted the resulting estimate will yield too high a bhp figure. It is this flywheel figure that everyone is interested in the posts so far not the more accurate chassis figures. You have said the estimates can be out by as much as 5% +/- which based on the estimated flywheel bhp (289.8 bhp in this case) would give a true bhp output of between 276 bhp and 305 bhp. That's a 29bhp margin which is still quite a lot.

As for your comments regarding bedroom tuners, this is a forum for discussion and debate. Naturally the levels of poster's knowledge varies and your input in these matters is, as you can see, very welcome so there's no point in getting too upset over inaccurate comments or unsubstantiated claims.

I think it would be a great idea if the club had a dyno day at TDP to see how your hub dyno works and compare outputs from previous dyno days. In business there's nothing better than demonstrating your product to silence its critics.

Frawls
 
[quote author=FRAWLS link=topic=11703.msg141573#msg141573 date=1231335963]
@Cathy.....Didn't TDP use a rolling road dyno before the hub dyno for rolling road days? If so that would mean that TDP outputs using the roller dyno were far less accurate than those using your new hub dyno as there were far more variables to contend with.

No one has argued that a hub dyno is less accurate than a rolling road dyno all things being equal. Obviously the closer the measurements are taken to the flywheel by their very nature the more accurate they should be. This is why a bench dyno aka engine dyno is more accurate than a hub dyno which in turn is more accurate than a rolling road dyno.

What is less obvious is the accuracy of the estimated flywheel power and torque which rely on the operator inputting the correct figures for transmission losses. If too high a transmission loss figure is inputted the resulting estimate will yield too high a bhp figure. It is this flywheel figure that everyone is interested in the posts so far not the more accurate chassis figures. You have said the estimates can be out by as much as 5% +/- which based on the estimated flywheel bhp (289.8 bhp in this case) would give a true bhp output of between 276 bhp and 305 bhp. That's a 29bhp margin which is still quite a lot.

As for your comments regarding bedroom tuners, this is a forum for discussion and debate. Naturally the levels of poster's knowledge varies and your input in these matters is, as you can see, very welcome so there's no point in getting too upset over inaccurate comments or unsubstantiated claims.

I think it would be a great idea if the club had a dyno day at TDP to see how your hub dyno works and compare outputs from previous dyno days. In business there's nothing better than demonstrating your product to silence its critics.

Frawls


[/quote]

Hi Frawls,

We have never had a rolling road. We have operated a Dynapack Evolution 8000 4wd system since 2002. Every year, we receive both hardware and software updates for the system, allowing it's accuracy and technology to be absolutely precise. In early 2008, the four load retarding units were also upgraded with brand new Evolution 10000 system, allowing us to measure up to 5000Nm / 3700lb/ft per axle at a max hub rpm of 2400. Equating to approx. 1800bhp per axle. The sensitivity of the system has now increased to a level where we can accurately measure as low as 25bhp per axle with an accuracy of 0.1%. Also, please note we have a temperature controlled dyno cell which uses six fans to change the air in the cell up to 20 times per minute. Allowing for real-time simulation of road cooling effects on all aspects of the car.

As I said, we would be more than happy to have an ISDC dyno day.

Regards,
Cathy.


@ Dan - That's cool with us :xmas_cheers:
 
Nice figures there Echo, looking sweet :thumbsup:

The fan stuck directly onto the intercooler could have made a little difference... doubt it would get that much air going through it on the road :ponder2:

I had my standard MY02 sti measured with tdp and it came out at 251bhp fly wheel, somewhere just above 200 at the hubs so I was disappointed to say the least :icon_sad: thats with water spray going too, made 10hp less without it... also wouldn't worry about people saying Robbie is out to inflate your ego with power figures, to be realistic, he's not a computer programmer and how could he ever adjust the figures???
Also, if you met the man, you know yourself he is not out to flatter you and its usually quite the opposite... I think its one of the reasons he has the reputation he does...

There also seems to be some debate over the estimated fly wheel power and where it comes from. When you car is on the dyno and reaches max rpm set on the dyno, the clutch is pressed and the drive train slows down naturally and calculates the power that way, the drive train friction and whatever else?? is measured and added to hub power to give you your estimated fly wheel power. The clutch is the last thing before the fly wheel on the drive train so it seems acurate to me

Hope an ISDC day does come up though, regardless of whether people think the figures are acurate or not, people could see the difference between each car without variables of tyres that you get on rollers... and you don't have to worry about some donkey sitting on your boot either, or straps to the ground or any of the negative parts of roller measurment, just nice printouts of what your car does :thumbsup:

Did you also happen to get the front rear torque split from him?? Interesting to know where a legacy puts its power down???
 
ya i did ill post it up after work more toruqe to the front by 100 i think ill scan it later for you
 
Good stuff, same as mine so, think I had 55% front to 45% back

Answered my questions on understeer
 
[quote author=Cill link=topic=11703.msg141599#msg141599 date=1231338956]
Nice figures there Echo, looking sweet :thumbsup:

The fan stuck directly onto the intercooler could have made a little difference... doubt it would get that much air going through it on the road :ponder2:

I had my standard MY02 sti measured with tdp and it came out at 251bhp fly wheel, somewhere just above 200 at the hubs so I was disappointed to say the least :icon_sad: thats with water spray going too, made 10hp less without it... also wouldn't worry about people saying Robbie is out to inflate your ego with power figures, to be realistic, he's not a computer programmer and how could he ever adjust the figures???
Also, if you met the man, you know yourself he is not out to flatter you and its usually quite the opposite... I think its one of the reasons he has the reputation he does...

There also seems to be some debate over the estimated fly wheel power and where it comes from. When you car is on the dyno and reaches max rpm set on the dyno, the clutch is pressed and the drive train slows down naturally and calculates the power that way, the drive train friction and whatever else?? is measured and added to hub power to give you your estimated fly wheel power. The clutch is the last thing before the fly wheel on the drive train so it seems acurate to me

Hope an ISDC day does come up though, regardless of whether people think the figures are acurate or not, people could see the difference between each car without variables of tyres that you get on rollers... and you don't have to worry about some donkey sitting on your boot either, or straps to the ground or any of the negative parts of roller measurment, just nice printouts of what your car does :thumbsup:

Did you also happen to get the front rear torque split from him?? Interesting to know where a legacy puts its power down???
[/quote]

Our dyno doesn't use the roll down method. This would not work on a Dynapack as the dyno itself and the vehicles drive-line have virtually no inertia so the second you press the clutch, the whole thing stops. We calculate the flywheel BHP by entering a fixed loss figure for the type of car. This figure is often obtained from the OEM or from either testing an engine in a car where the engine has been on an engine dyno or the drive-line drag has been tested by the use of an electric motor. We as in the top Dynapack users in the world, share this information so as to help each other out and to give the most accurate figures to our customers. In the case of Echo's car, we do not have a Subaru Legacy B4 figure but used a figure for the WRX that uses the same type transmission. Even with careful calculation of the vehicle type, differences can occur due to the viscosities of the oil used in the transmissions may not be the same. Hence the +/- 5%
 
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