Anyone did an underdrive pulley?

[SRSANDS]

I am in the middle of an timing belt, water pump and tensioner job. I have an extra commuter car so I am taking my time to do the job and learning a great deal in the process. The question I have I was thinking about putting a underdrive pulley in it while its opened up. Has anyone purchased and installed one of these in their Tundra? Is it worth the money and noticable? Will I need a diffrent belt or does the accessory tensioner adjust to the new size pulley? Please let me know before I fork out the extra 150 for it. Thank you.

[apimpdad]

i have had one on my truck for about 5000 miles and i like it. i did notice a small gain in mpg and power. the only drawback is that the headlights dim (only when you are parked and the rpms are low) but who cares about that. you will need to buy a smaller belt, that is it

[SRSANDS]

Where can I find this Underdrive pulley for a good deal?

[Mr. Creosote]

Originally Posted by apimpdad

the headlights dim (only when you are parked and the rpms are low)

Replacing some or all external bulbs with LEDs will help this.