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Started by cao, April 05, 2006, 03:32:00 PM

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cao

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 ;)

hitmanGTI

interesting....

My read showed

145 Hp at the Wheels...

without an exhaust

hitmanGTI

Quote from: cao on April 05, 2006, 05:12:23 PM
Found another on the web with 131hp at the wheels
But also others which say 140hp so i dunno

Yours is an AGU to isn't it?

yurr!!

AGU hard!

Audi-man


My 1.8T Audi dynoed at 134hp with only 0.34 bar / 5PSI. My boost was low due to a stuffed Boost Control Valve at the time. So with the BCV fixed I would have expected the car to have 140-something BHP easy.

You should have a little more BHP I would have thought? But not too far off. Are you getting a new DV? I'd say a new forge DV would bring you up to over 140 BHP. The standard Audi ones are sh*t and stuff out pretty easy.


Say the Wett chip gives you 190 BHP in a car producing 150 BHP. Will be interesting to see if your car has 190 BHP with the Wett chip or about 15 BHP less?

hitmanGTI

sorry did i mention my first dyno was with a stuffed DV..

Audi-man

You torque peaks really early (which is good as your car will be quick down low) but drops off pretty fast. I would expect this chart to be flipped with peak torque at about 3500-4000rpm?

Can you find other dyno charts for your car to compare?




Simon MkII

Quote from: MK4 GTI on April 05, 2006, 04:47:42 PM
interesting....

My read showed

145 Hp at the Wheels...

without an exhaust

As Tom mentioned, it's pretty much pointless to compare dyno graphs unless they are both done on the exact same dyno on the same day.
Mazda Mx5

Audi-man

Quote from: cao on April 05, 2006, 07:27:27 PM
They seemed to think 132 was about right for 150

I have unleashed VWVortex on them


Sounds all good then. Besides I don't know jack squat!

Audi-man

Opps - did you say 132BHP at the wheels, not calibrated back to the engine? Allowing for the 15% power loss, you'd have bang on 150BHP!!!!!!!!!!!!!!

Have just cut a pasted an interesting article on the net about Dyno conversions FYI;




Testing, Testing
Factory ratings are all well and good, but many enthusiasts modify their cars and then want to see how much of an improvement they got from their labors. The problem is that most of the time people are not interested in ripping the engine out of their car to have it tested on an engine dyno; no, they're going to be testing on a chassis dyno. The most common chassis dyno, the inertial dynamometer (popularized by DynoJet), measures the horsepower as delivered at the power wheels -- whether front or rear.
But testing rear-wheel horsepower (rwhp -- obviously, front drivers would be measuring fwhp) makes it difficult to convert from what the dyno says to what the manufacturer says. The manufacturer, remember, measures horsepower at the flywheel. All that equipment between the engine and the wheels -- the transmission, driveshaft, differential, and axles -- introduce friction and inertial losses summarized as "powertrain loss" or "parasitic losses". The efficiency of the driveline can greatly affect the amount of the powertrain loss: Ford's AOD transmission, for example, is notoriously inefficient. As a very general rule, rear-wheel horsepower on a manual-transmission car is about 15% less than SAE net, and rear-wheel horsepower on an automatic-transmission car is about 20% less than SAE net.

Even looking at dyno numbers, though, it's important to exercise some caution. Dynos measure horsepower under the conditions of the day, then apply a mathematical conversion to bring the numbers in line with SAE J1349. The raw numbers can vary substantially. In one dyno test of a 1998 Firebird conducted several days apart, the same car ran a raw number of 284 horsepower one day, and 299 horsepower on a rather colder day. Corrected, both numbers were within half a horsepower of each other. The corrected numbers are useful for comparing this car to other cars, or the same car after different modifications spanning a long time, but in the real world a car's horsepower isn't corrected: on a dragstrip, the Firebird would have been about a tenth quicker on the day it was making 299 horsepower than on the day it was only making 284.


Vapor Horsepower?
For people in the habit of thinking about SAE net horsepower, or old musclecar enthusiasts accustomed to SAE gross numbers, looking at real-world rear-wheel horsepower can be quite a wake-up call. This 1970 Charger makes an excellent example. Its 318 was factory rated in 1970 at 230 horsepower (SAE gross). But on the dyno it came just short of 150 horsepower (corrected rear-wheel). Where did that 80 horsepower go?
Since that Charger is an automatic, roughly 20% of it went to turning the drivetrain. That puts it at somewhere around 188 SAE net horsepower (or to use American manufacturers' penchant for rounding up, 190). But since the factory number uses SAE gross, there's another 20% difference. And that puts us at 235 horsepower, just about where it needs to be. It all adds up, and the same engine can have an 80 hp difference through no other fault than the means by which the power is measured.

Things get real interesting when the numbers don't add up. Dyno testing proved that General Motors was lying about the low horsepower numbers in the F-body when compared to the same engine in the Y-body. Hot Rod magazine gathered a collection of performance cars and dyno tested them for the May 1998 issue. They found 292 rwhp for a Firebird Trans Am and 286 rwhp for a Corvette. The slight difference between the cars is likely due to varying build tolerances; certainly not enough to say one engine's design is notably different from the other's. Either way, the LS1 is looking at about 340 SAE net horsepower in 1998, nearly on the money for the Corvette's factory rating (345) but way aboveboard for the Firebird's (305). By comparison, the 1998 SVT Mustang Cobra was also rated at 305 horsepower but on the dyno it only delivered 257 rwhp -- just right for a 15% powertrain loss. And the chart on this Camaro page seems to support the underrating of the F-body cars by looking at the performance numbers it posts compared to other vehicles with higher rated horsepower (and higher price tags). In this case, the vapor horsepower is the power loss from when the SAE net horsepower was converted into ad copy.


hitmanGTI

Quote from: cao on April 05, 2006, 07:53:16 PM
Yes 132hp at the wheels  ;D
Am slightly concerned with the shape of the torque curve shouldn't be dropping so early I think, does a corrilation between this and the AFR becoming quickly richer make sense.

But boost is constant over this period so its not like boost is escaping? just more fuel being added

Anyone have AFR plots

I think your Torque Curve is Slightly Alarming.. how bumpy it is..

mine was like a table top.. dick all fluctuation... :/

Audi-man


Ha ha  hee hee - Its never simple!

Audi-man

Quote from: MK4 GTI on April 05, 2006, 08:05:44 PM
I think your Torque Curve is Slightly Alarming.. how bumpy it is..

mine was like a table top.. dick all fluctuation... :/

Yeah A4 1.8T's are the same. The little turbo is all about the flat (or linear) torque cure!

I'm really surprised you have max BHP without max boost? I don't know this for certain. But an educated guess would say you'd be max boosting to get max BHP?

hitmanGTI

#12
Quote from: Audiman on April 05, 2006, 08:09:50 PM
Yeah A4 1.8T's are the same. The little turbo is all about the flat (or linear) torque cure!

I'm really surprised you have max BHP without max boost? I don't know this for certain. But an educated guess would say you'd be max boosting to get max BHP?

its normal to not have max boost at the high end..

Im still trying to find Dyno Sheets

hitmanGTI

Quote from: cao on April 06, 2006, 05:42:47 PM
Ok confirmed 132hp at the wheels
Basil said this was actually a little more than would expect from stock
It is being chipped tomorrow morning and should be going again tomorrow afternoon

Mine had to come from germany as it is uncommon ECU, but the germans emailed Basil and said that my ECU/Engine is particularly responsive to chipping  >:D loosely translated to "it will go like stink"

we'll have to have a drag whence i haft my chipper in..

cao

Don't know if drags are really my thing prefer twisty hill roads
Anyway we all know who would win  :laugh:

RS ZWEI

Race tracks boys.

cao, where in the country do you live?
1980 VW Golf GTI Track Car
1995 Audi RS2
2003 Mini Cooper S (Written off - rear ended)
2005 Mini Cooper S
2006 Skoda Octavia vRS Combi
2009 Renault Megane 230 R26 (Written off - rear ended)
2013 Renault Megane RS265 Redbull RB8

hitmanGTI

Quote from: Golfboy666GTI on April 06, 2006, 08:00:14 PM
Race tracks boys.

cao, where in the country do you live?

Nah State highway 25a lol jokes..

Yeah i meant a controlled environment..

cao