what has an U/D done for you?
02-28-2008, 08:57 PM
#62
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I installed an underdrive pulley on my T/A and did notice better track times. Even some of the people racing each week noticed my T/A was faster with the UD pulley, came off the line quicker, was able to spin my tires easier also.
That being said, I also had problems with it. While sitting in line to race my battery went dead, my car was also harder to steer especially when parking. My turn signals struggled as well, windows rolled up slowly.
For an A4 car I don't know if it's a wise mod or not. I ended up taking mine off because of the steering issues, maybe a lowered f-body steers harder.
That being said, I also had problems with it. While sitting in line to race my battery went dead, my car was also harder to steer especially when parking. My turn signals struggled as well, windows rolled up slowly.
For an A4 car I don't know if it's a wise mod or not. I ended up taking mine off because of the steering issues, maybe a lowered f-body steers harder.
02-29-2008, 03:42 PM
#64
I installed an underdrive pulley on my T/A and did notice better track times. Even some of the people racing each week noticed my T/A was faster with the UD pulley, came off the line quicker, was able to spin my tires easier also.
That being said, I also had problems with it. While sitting in line to race my battery went dead, my car was also harder to steer especially when parking. My turn signals struggled as well, windows rolled up slowly.
For an A4 car I don't know if it's a wise mod or not. I ended up taking mine off because of the steering issues, maybe a lowered f-body steers harder.
That being said, I also had problems with it. While sitting in line to race my battery went dead, my car was also harder to steer especially when parking. My turn signals struggled as well, windows rolled up slowly.
For an A4 car I don't know if it's a wise mod or not. I ended up taking mine off because of the steering issues, maybe a lowered f-body steers harder.
02-29-2008, 04:42 PM
#65
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Your welcome. I don't want to discourage anyone from doing this pulley mod because it may work out for your car.
The fact that an A4 car idles at a lower RPM puts the vehicle at a disadvantage possibly for the pulley mod.
It was a tough choice deciding to take it off because there were two cars that I couldn't beat before I did the mod, after the pulley I beat both of them that night, one was a 70 Mustang CJ trailered in and tubbed, the other was a 67 olds 442 w/ 455 and I beat them both with the pulley mod.
So to compensate for the power loss of putting the stock pulley back on I had a Nitrous kit put on with a 100 wet shot
The next week I pulled two car lengths on those same cars on a 1/8 th. track with the 100 shot, they about **** themselves when I flipped the switch and jumped two cars on them. The guy with the tubbed and trailered Mustang couldn't beleive he was getting beat by a factory stock motor with a smooth idle. I have that on video tape beating a built 428 CJ that runs 12.5s all day long at PR in Seattle. It's a thing of beauty....the LS1.
The fact that an A4 car idles at a lower RPM puts the vehicle at a disadvantage possibly for the pulley mod.
It was a tough choice deciding to take it off because there were two cars that I couldn't beat before I did the mod, after the pulley I beat both of them that night, one was a 70 Mustang CJ trailered in and tubbed, the other was a 67 olds 442 w/ 455 and I beat them both with the pulley mod.
So to compensate for the power loss of putting the stock pulley back on I had a Nitrous kit put on with a 100 wet shot
The next week I pulled two car lengths on those same cars on a 1/8 th. track with the 100 shot, they about **** themselves when I flipped the switch and jumped two cars on them. The guy with the tubbed and trailered Mustang couldn't beleive he was getting beat by a factory stock motor with a smooth idle. I have that on video tape beating a built 428 CJ that runs 12.5s all day long at PR in Seattle. It's a thing of beauty....the LS1.
03-01-2008, 02:53 PM
#66
I installed an underdrive pulley on my T/A and did notice better track times. Even some of the people racing each week noticed my T/A was faster with the UD pulley, came off the line quicker, was able to spin my tires easier also.
That being said, I also had problems with it. While sitting in line to race my battery went dead, my car was also harder to steer especially when parking. My turn signals struggled as well, windows rolled up slowly.
For an A4 car I don't know if it's a wise mod or not. I ended up taking mine off because of the steering issues, maybe a lowered f-body steers harder.
That being said, I also had problems with it. While sitting in line to race my battery went dead, my car was also harder to steer especially when parking. My turn signals struggled as well, windows rolled up slowly.
For an A4 car I don't know if it's a wise mod or not. I ended up taking mine off because of the steering issues, maybe a lowered f-body steers harder.
Thats interesting...Ive never heard of that happening before, has anyone had similar problems with a M6?
03-01-2008, 04:26 PM
#67
An M6 shouldn't have a problem with an underpulley.
Consider this.
M6 cars idle at 800 rpm stock
A4 idles at 600rpm in gear stock
With the underpulley at 25% reduction in accessory speed, then it will be as if the accessories are running at 600rpm. Everything should be just fine as the waterpump, the power steering, A/C and alternator are identical between A4 and M6 cars.
For added protection though, I put in an overdrive pulley for my alternator in my m6 car. For everything else, an m6 car shouldn't really notice a difference except if you bring the rpm down below idle and you will see a dip in voltage.
Consider this.
M6 cars idle at 800 rpm stock
A4 idles at 600rpm in gear stock
With the underpulley at 25% reduction in accessory speed, then it will be as if the accessories are running at 600rpm. Everything should be just fine as the waterpump, the power steering, A/C and alternator are identical between A4 and M6 cars.
For added protection though, I put in an overdrive pulley for my alternator in my m6 car. For everything else, an m6 car shouldn't really notice a difference except if you bring the rpm down below idle and you will see a dip in voltage.