A4 25% underdrive pulley guys
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From: North East, MD
A4 25% underdrive pulley guys I didn't get an overdrive alternator pulley and my car was fine during the Summer and Fall. But this cold weather today I went to start the car and nothing. I noticed the last couple of times windows went slow and it was noticeably down on juice. After driving it a couple of days it was fine but I think not having an overdrive it doesn't put enough in the battery to keep things good. So it appears unless I find a bad battery that it is needed! So anyone know where to get one?
If you live in a warm climate you may be okay.
If you live in a warm climate you may be okay.
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11 Second Club
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From: North East, MD
True. I don't drive the car for a week or two at a time but I plan on keeping tabs on it. I jumped the car off this morning and drove it all day. Tonight it is sitting on a trickle charge and I will see how it acts over the weekend since we will be working on it. Pulley from WS6 Store should be here next Monday.
Alternator current output drops off VERY VERY fast at low RPM...so if you have stock rearend gears and a tranny with an overdrive still...I'd bet your RPM is low enough that you're just not charging the battery most of the time you're driving. I'd especially expect that exact problem in say a T56 car...my car with 3.42's goes down the highway at 75 mph at 1700 or so RPM (depends if I have the winter or summer tires on it)...I'd never ever consider an underdrive pulley because of that. I run an optima yellow top, and it's been fantastic firing my car right up in sub zero temperatures the past 2 winters...but I have no doubt that with the alternator running 25% slower, my car wouldn't crank in the morning.
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If your car isn't charging at any less than 1700 rpm's, you have some charging issues.
You only "need" 12.6v of alternator output to be considered "adequately charging", although 13.2v is considered pretty decent.
Mine charges 13.4v or so at idle, and 14.0v or better at any cruise rpm.
I've had a 25% UD crank pulley on my car for 2 winters now, and it fires up instantly whether it's been sitting outside in the cold for 2 weeks, or whether I just idled in traffic all day long with wipers, defroster, and headlights on.
For reference, my car is A4 with 3600 stall, and 342 gears...and a known good battery.
You only "need" 12.6v of alternator output to be considered "adequately charging", although 13.2v is considered pretty decent.
Mine charges 13.4v or so at idle, and 14.0v or better at any cruise rpm.
I've had a 25% UD crank pulley on my car for 2 winters now, and it fires up instantly whether it's been sitting outside in the cold for 2 weeks, or whether I just idled in traffic all day long with wipers, defroster, and headlights on.
For reference, my car is A4 with 3600 stall, and 342 gears...and a known good battery.
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