Europipe for GT3
12-15-2003, 07:51 PM
#32
Nordschleife Master
Thread Starter
European Dyno's
Spoke with Stef at Europipe. The figure that one should be concerned about is the engine HP increase from stock pipe to europipe. The figures for wheel acheivement are correct, but cannot be used for a reliable rwhp figure. One has to use the an American dyno to get rwhp, whereas the European style dynos measure drivetrain loss and use computer software to accurately determine engine HP. Due to many factors, the conversion factors used to convert American rwhp to engine hp can vary between 0 -10hp and are not necessarily reliable. Here is Stef's quoted explanation:
The professional service and demeanor of this company cannot be overemphasized. I sent him an email last night about this and he responded via email and he took the time to call me personally from Belgium on my cell to discuss the dyno results while I was skiing today up at Killington, VT. Nothing like skiing two feet of powder and hearing the cell phone ring then talking Porsche on the slopes. Pretty cool to say the least!!!
Summary: +12 HP flywheel, +8 lbs/ft torque at the flywheel
Hope this clears up the confusion...So if I want to get a reliable rwhp figure I will need to dyno my car here.
"So the difference between an American and a European dyno is that with the European brands you can actually measure the drive train loss and with the American dynos you can not .
The most common European dynos are BOSCH and MAHA .
Put the car on the rolling road(the dyno machine) and after the warm up procedure you shift from first gear to fifth gear . ( 5 th gear ratio = 1:1 on a GT3 ) Run the engine past the max hp rpm range . Then depress the clutch pedal and put into neutral . Now the dyno will measure the drive train loss . Let the car slow down without touching the brakes .
The uncorrected rear wheel hp + the drivetrain loss = uncorrected engine hp.
The dyno software will correct these results to standard ambient conditions
based on DIN 70020 , 780 mmHg ( 1013 pa ) barometric pressure and
20° C temperature .
The drivetrain loss will vary according the rpm range ( greater loss at
higher rpm ) , the type of tires ( street compound or sticky slicks ) ,
tires pressure , temperature of the tires , transmission temperature , etc .
If the dyno can only measure rearwheel horsepower (American Dyno's) , one has to multiply the rwhp with a x-factor to obtain a guesstimated flywheel horsepower .
As the drivetrain loss will vary according the conditions at a given time
(0 - 10 hp differences ), you cannot rely on the rwhp alone to determine
changes of the flywheel horsepower ."
The most common European dynos are BOSCH and MAHA .
Put the car on the rolling road(the dyno machine) and after the warm up procedure you shift from first gear to fifth gear . ( 5 th gear ratio = 1:1 on a GT3 ) Run the engine past the max hp rpm range . Then depress the clutch pedal and put into neutral . Now the dyno will measure the drive train loss . Let the car slow down without touching the brakes .
The uncorrected rear wheel hp + the drivetrain loss = uncorrected engine hp.
The dyno software will correct these results to standard ambient conditions
based on DIN 70020 , 780 mmHg ( 1013 pa ) barometric pressure and
20° C temperature .
The drivetrain loss will vary according the rpm range ( greater loss at
higher rpm ) , the type of tires ( street compound or sticky slicks ) ,
tires pressure , temperature of the tires , transmission temperature , etc .
If the dyno can only measure rearwheel horsepower (American Dyno's) , one has to multiply the rwhp with a x-factor to obtain a guesstimated flywheel horsepower .
As the drivetrain loss will vary according the conditions at a given time
(0 - 10 hp differences ), you cannot rely on the rwhp alone to determine
changes of the flywheel horsepower ."
Summary: +12 HP flywheel, +8 lbs/ft torque at the flywheel
Hope this clears up the confusion...So if I want to get a reliable rwhp figure I will need to dyno my car here.
12-15-2003, 11:54 PM
#33
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Re: European Dyno's
Originally posted by rockitman
The figures for wheel acheivement are correct, but cannot be used for a reliable rwhp figure. One has to use the an American dyno to get rwhp,
The figures for wheel acheivement are correct, but cannot be used for a reliable rwhp figure. One has to use the an American dyno to get rwhp,
What you put to the ground is the important number.
AutoDyn Performance Automotive Chassis Dynamometer by Superflow are one of the leaders in the race community. Find one close to you for your tests.
http://www.superflow.com/TestCenters/locator.html
12-16-2003, 12:19 AM
#34
Nordschleife Master
Thread Starter
And your point 
With all other things equal, engine HP is what I am concerned about in addition to Exhaust note, throttle response and torque...If you increase engine horsepower, you also increase rwhp accordingly... What basis do you have to pass judgement on the validity of EP claims. I have spoken with people that have verified EP's claims with their own cars.
I am growing tired of your "you have proably not exercised your car at anywhere near it's max potential you will never really feel a difference" jibberish. Buy your own GT3 and stop trying to live vicariously through mine!!!
With all other things equal, engine HP is what I am concerned about in addition to Exhaust note, throttle response and torque...If you increase engine horsepower, you also increase rwhp accordingly... What basis do you have to pass judgement on the validity of EP claims. I have spoken with people that have verified EP's claims with their own cars.
I am growing tired of your "you have proably not exercised your car at anywhere near it's max potential you will never really feel a difference" jibberish. Buy your own GT3 and stop trying to live vicariously through mine!!!
Last edited by rockitman; 12-16-2003 at 06:47 PM.
12-16-2003, 01:11 AM
#35
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I agree - If someone wants to add an exhaust and discuss its performance gains, so be it!! Most of us may never drive our cars to its limit, but so what?? For many of us this is a hobby and doing these mods to get more enjoyment out of it is part of the fun.
Please, everyone, stop bashing people for posting their findings and opinions just because you may personally not think it necessary. Leave your car alone and enjoy it just the same - we wont give you sh*t about it... I promise..
Rockit - I am still eagerly awaiting your results. Please post as much information as you can. I thoroughly welcome and enjoy it..
Adam
Please, everyone, stop bashing people for posting their findings and opinions just because you may personally not think it necessary. Leave your car alone and enjoy it just the same - we wont give you sh*t about it... I promise..
Rockit - I am still eagerly awaiting your results. Please post as much information as you can. I thoroughly welcome and enjoy it..
Adam
12-19-2003, 02:03 AM
#36
The Rebel
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Hey Rockitman,
This is a hobby for all of us. I raced professionally in Europe for awhile but now, the only thing I worry about at the track is beaten my own times and more importantly having fun. If anyone wants to do this seriously, they wouldn't buy a GT3 but a GT3R. I too am interested in hearing what the exhaust will sound like after all its about enjoying these wonderful toys. Enjoyment comes in many ways. If you get a HP increase consider it icing on the cake.
This is a hobby for all of us. I raced professionally in Europe for awhile but now, the only thing I worry about at the track is beaten my own times and more importantly having fun. If anyone wants to do this seriously, they wouldn't buy a GT3 but a GT3R. I too am interested in hearing what the exhaust will sound like after all its about enjoying these wonderful toys. Enjoyment comes in many ways. If you get a HP increase consider it icing on the cake.
12-19-2003, 07:36 PM
#37
Nordschleife Master
Thread Starter
Originally posted by MJSpeed
Hey Rockitman,
This is a hobby for all of us. I raced professionally in Europe for awhile but now, the only thing I worry about at the track is beaten my own times and more importantly having fun. If anyone wants to do this seriously, they wouldn't buy a GT3 but a GT3R. I too am interested in hearing what the exhaust will sound like after all its about enjoying these wonderful toys. Enjoyment comes in many ways. If you get a HP increase consider it icing on the cake.
Hey Rockitman,
This is a hobby for all of us. I raced professionally in Europe for awhile but now, the only thing I worry about at the track is beaten my own times and more importantly having fun. If anyone wants to do this seriously, they wouldn't buy a GT3 but a GT3R. I too am interested in hearing what the exhaust will sound like after all its about enjoying these wonderful toys. Enjoyment comes in many ways. If you get a HP increase consider it icing on the cake.
Happy Holidays...
12-28-2003, 03:34 AM
#43
Nordschleife Master
Thread Starter
Originally posted by Johninrsf
Rockitman,
Do you know the weight difference between the EP and stock exhausts? Thanks,
JP
Rockitman,
Do you know the weight difference between the EP and stock exhausts? Thanks,
JP
12-28-2003, 06:17 PM
#44
Rennlist Member
Interesting numbers would be those of the power train horsepower losses at different RPM derived on the Bosch or MAHA dyno...these could then be used to correct an American dyno's result.
01-01-2004, 09:06 PM
#45
Nordschleife Master
Thread Starter
Europipe Installed
Just finished the GT3 Europipe install. Took about 5 1/2 hours all told till test drive. Immediately noticed the deeper/warmer/screamier exhaust note, noticeably improved throttle response. The power seems more immediate on demand than before. Anyways, I will eventually redyno the car for the ultimate litmus test for the HP increase. I am confident that the claims of the MFG are true. I will expect rwhp to be in excess of 360, using the conservative drive train loss factor of 15%...360/.85 = 423 Flywheel HP estimate. Not bad for an NA car. Here's a pic prior to the rear bumper going back on. As always, I have detailed pics of the complete install and will be putting together an install gallery for everyone's pleasure... 
Before:
After:
Before:
After:
Last edited by rockitman; 09-19-2014 at 07:32 PM.