Zasker1

So a question for the group, I have read articles on the RSX, VW Vortex, Honda and Infinity boards and I am at a loss as to weather or not a lightened crank pull is truly detrimental to an engine. As there are hundreds of posts that go either way. The one item that I do see reoccurring is that if you are going to do this it is best to do on a newer motor rather than a tired motor that has been revved to 10k RPM 10,000 times. Does anyone on this board have actual experience with this part from a car they previously owned. I personally know of only two people that have ever installed this on their cars but as they sold both cars before hitting the big 100k miles, its hard to say if this will lessen the longevity of the motor. I will probably buy this part regardless as I tend to get a new car every 4 years so I am not worried to much about it failing while I own it. My only real concern is that with the under drive I will probably want to buy a better battery like a yellow top to supplement the powerless. (CAP's wont help)

What does everyone think about this,

sauceman

My first post on HT.com when I was a n00b with message forums was about this. Here's what I got:

http://www.honda-tech.com/zerothread?id=319189

Zasker1

Intresting read, jury is still out

JTso

iTrader: (2)

If your concern is low battery voltage, then buying a different battery is not going to help you. When you start the engine with an underdrive alternator pulley, there will be lower voltage to power electrical accessories like heater fan, headlights, rear defroster, stereo, windshield wiper motor, basically all items you would normally use on a rainy day. You might even notice the headlights flicker when turning on your turn signal. Additionally, the same underdrive alternator is not going to put out enough power to recharge the battery that was used to crank the starter. What that means is, the battery will become dead overtime if this undercharge condition is not corrected.

The battery is normally at 12v, when the engine is started with a normal alternator, the alternator will put out approx. 14.5v at around 3000 rpm and stays within that range, controlled by the voltage regulator. When the battery voltage is down to approx. 10.5v due to low alternator output, it might not be enough power to crank the starter anymore. You can easily test this by connecting a digital meter to the battery and monitor the voltage change. I have installed AEM underdrive pulleys on my Civic, and promptly removed them, then sold them on ebay.

Zasker1

oh, I am buying a better battery as the factory battery is crap, 17k miles and it dies if I leave my stereo on for 10min. I had planned to buy a yellowtop from the getgo as I like to listen to toons with my engine off. I have already asked UR for a rough price quote of getting a slignly smaller Altenator pully made to offset the underdrive if I go that route.