Question
07-05-2007, 11:55 PM
#1
Le Mans Master
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Question
I've had my car dyno'd by two different tuners, both are great. One tuner locks the TC on my A4.
The other tuner doesn't lock the TC.
The TC is a stock.
Which is the correct way of doing it?
Thanks,
Sleeper
The other tuner doesn't lock the TC.
The TC is a stock.
Which is the correct way of doing it?
Thanks,
Sleeper
07-06-2007, 10:16 AM
#2
Drifting
The locked TC will give you a higher number, but if your tune isn't set up to lock your TC at WOT, then the other tuner who left it unlocked is giving you a more "realistic" number compared to what you'll see on the street.
I don't know enough about autos to tell you which is "correct" but usually I hear most tuners locking the TC for dyno pulls.
I don't know enough about autos to tell you which is "correct" but usually I hear most tuners locking the TC for dyno pulls.
07-06-2007, 06:24 PM
#3
Le Mans Master
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St. Jude Donor '13-'14-'15
No real correct way to do it--more of a preference--I prefer to un-lock it as when you're racing or just driving hard the converter will always unlock when going to WOT so dynoing it that way gives you a more "real world" comparison--
07-06-2007, 11:16 PM
#4
Le Mans Master
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I fully understand now.
Basically locking the TC on the dyno will give you higher dyno numbers and having it unlocked is the realistic street rwhp numbers.
Like said dynoing is for bragging rights and a street tune is for fine tuning and realistic performance.
Thanks for the replies,
Sleeper
Basically locking the TC on the dyno will give you higher dyno numbers and having it unlocked is the realistic street rwhp numbers.
Like said dynoing is for bragging rights and a street tune is for fine tuning and realistic performance.
Thanks for the replies,
Sleeper
Last edited by SLPRC5; 07-06-2007 at 11:31 PM.
07-07-2007, 09:00 AM
#5
Melting Slicks
Locking the converter takes the slip out of the equation. It makes it one to one like its supposed to be.
Running them unlocked does 2 things.
1: It doesnt show an accurate HP number, because of the slip.
2: It allows the converter to flash, if you hit the throttle at the right time, which in turn gives a false torque reading, or spike.
When I dyno autos, I dont just lock the converter, I lock them in 3rd gear also. That way you can start the pull earlier in the RPMs and get a nice, true graph both torque and HP. Without the car wanting to down shift on you.
I've had cars with pretty high stalls, and done some tests locked and unlocked. I have seen differences of over 30 RWHP between locked and unlocked. The higher your stall, the more of a sponge effect.
Running them unlocked does 2 things.
1: It doesnt show an accurate HP number, because of the slip.
2: It allows the converter to flash, if you hit the throttle at the right time, which in turn gives a false torque reading, or spike.
When I dyno autos, I dont just lock the converter, I lock them in 3rd gear also. That way you can start the pull earlier in the RPMs and get a nice, true graph both torque and HP. Without the car wanting to down shift on you.
I've had cars with pretty high stalls, and done some tests locked and unlocked. I have seen differences of over 30 RWHP between locked and unlocked. The higher your stall, the more of a sponge effect.
07-07-2007, 09:02 AM
#6
Melting Slicks
Locking them gives you the realistic numbers. Just as realistic as if you had a M6. With a clutch, no slip. Does that mean that M6 numbers are unrealistic?
07-07-2007, 11:00 PM
#8
Le Mans Master
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Locking the converter takes the slip out of the equation. It makes it one to one like its supposed to be.
Running them unlocked does 2 things.
1: It doesnt show an accurate HP number, because of the slip.
2: It allows the converter to flash, if you hit the throttle at the right time, which in turn gives a false torque reading, or spike.
When I dyno autos, I dont just lock the converter, I lock them in 3rd gear also. That way you can start the pull earlier in the RPMs and get a nice, true graph both torque and HP. Without the car wanting to down shift on you.
I've had cars with pretty high stalls, and done some tests locked and unlocked. I have seen differences of over 30 RWHP between locked and unlocked. The higher your stall, the more of a sponge effect.
Running them unlocked does 2 things.
1: It doesnt show an accurate HP number, because of the slip.
2: It allows the converter to flash, if you hit the throttle at the right time, which in turn gives a false torque reading, or spike.
When I dyno autos, I dont just lock the converter, I lock them in 3rd gear also. That way you can start the pull earlier in the RPMs and get a nice, true graph both torque and HP. Without the car wanting to down shift on you.
I've had cars with pretty high stalls, and done some tests locked and unlocked. I have seen differences of over 30 RWHP between locked and unlocked. The higher your stall, the more of a sponge effect.
