I have an underdrive crank pulley and I must say it's great. Low-end torque is freed up which for an automatic is huge. I could tell the difference with it when I went up a steep hill in my old neighborhood. The car used to have to downshift from 3rd into 2nd to tackle it. No longer!
I've been on the udp for about 20k miles. No problems. I've taken a nonstop 7.5 hour trip with no coolant problems. I have an aftermarket head unit that does draw more power. The alternator has had no problem keeping my batteries charged, though. Just more noticeable headlight dimmage at idle.
I'd love to some day get the accessory pulleys too just to help free up even more hp. Some day...
I've been on the udp for about 20k miles. No problems. I've taken a nonstop 7.5 hour trip with no coolant problems. I have an aftermarket head unit that does draw more power. The alternator has had no problem keeping my batteries charged, though. Just more noticeable headlight dimmage at idle.
I'd love to some day get the accessory pulleys too just to help free up even more hp. Some day...