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Posted: Fri Mar 14, 2008 9:14
by Buffalo
Came across some Agency Power pulleys. Anyone have one? Pros and cons?
Talked to a friend and he said that the light flywheel and pulleys were a bad combo. Any info on the rotory?

http://www.vividracing.com/catalog/agency-...03-p-13195.html

Help please.

Posted: Fri Mar 14, 2008 9:14
by Huzer21
Definitely not a power mod, this is more of a driveability (even that's been debated), from what I've gathered. The 9hp that is claimed is horsehockey. I haven't heard of any correlation between underdrive pulleys and a lighter flywheels, though.

That said, I know a lot of people have bought them.

Posted: Fri Mar 14, 2008 9:14
by GR-8
I have no idea. Never heard of such a thing. Icon (dennis) has underdrive pulleys I believe.

Posted: Fri Mar 14, 2008 9:14
by MazdaTom
<div class='quotetop'>QUOTE (Huzer21 @ Mar 14 2008, 03:04 PM) [url=index.php?act=findpost&pid=32553]<{POST_SNAPBACK}>[/url]</div>
Definitely not a power mod, this is more of a driveability (even that's been debated), from what I've gathered.[/b]


Driveability issues from the lightweight flywheel? The first day or so with the new flywheel is kinda like relearning how to drive a clutch, but after that you adapt and everything is honky-dory. Awesome mod. Highly recommended.

Posted: Fri Mar 14, 2008 9:14
by Huzer21
<div class='quotetop'>QUOTE (MazdaTom @ Mar 14 2008, 03:17 PM) [url=index.php?act=findpost&pid=32559]<{POST_SNAPBACK}>[/url]</div>
Driveability issues from the lightweight flywheel? The first day or so with the new flywheel is kinda like relearning how to drive a clutch, but after that you adapt and everything is honky-dory. Awesome mod. Highly recommended.[/b]


Not the flywheel (he already has that). The pulleys.

Posted: Fri Mar 14, 2008 9:14
by Army RX8
"An Underdrive pulley refers to an aftermarket crankshaft or accessory pulley (such as an alternator pulley) that is designed to drive a vehicle's accessories at a slower rate than stock. Underdrive from the crankshaft pulley means the pulley is smaller that the original pulley it replaces. Overdrive from the accessory pulley means the pulley is larger than the original pulley it replaces. Originally they were invented for race cars in the 1950s and 60s, whose engines had been modified and ran at higher RPMs for longer periods of time than the manufacturers had intended. It was therefore necessary to underdrive the belt-driven accessories (among other things like the water pump) to keep the accessories from burning out and the engines running reliably. Underdrive pulleys did not become mainstream until the mid to late 1980's with their introduction from March Performance for fuel injected 5.0L Mustangs, Camaros & Trans Ams. They also appeared for small displacement engines in the mid-nineties with the entry into the market of Unorthodox Racing"

They're good on V-8's but as for our end of the world i dont really know. I guess it depends on how you drive. If you constantly max out your gears then i suppose they'd be a good idea. As for Compatability with Flywheels ive never heard anything bout that.

Posted: Fri Mar 14, 2008 9:14
by Buffalo
Sounds like it's not worth the money. Thanks for the info guys.

Posted: Fri Mar 14, 2008 9:14
by goldrocket
More importantly, "power pulleys" slow your water pump, and lower cooling capacity. And in a rotary that is a cardinal sin. It only takes one overheat to kill it.

Posted: Fri Mar 14, 2008 9:14
by MazdaTom
I have an underdrive crankshaft pulley on my Protege. It helped to restore the low end that I lost when I added the header. And my accessory pullies are lightweight aluminum pullies.

Anytime you can reduce rotating weight, it will be beneficial.

Posted: Fri Mar 14, 2008 9:14
by Buffalo
So perhaps i can look for a lightweight pulley instead of an underdriven one? Is that sound like a better idea?

Posted: Fri Mar 14, 2008 9:14
by GR-8
I thought that the aftermarket underdrive pulleys are lightweigt?

Posted: Sat Mar 15, 2008 9:14
by Huzer21
I haven't found any standard size lightweight pulleys, but then again, I haven't really searched for them. If anyone does fine some, let me know!

Posted: Sat Mar 15, 2008 9:14
by rx8ghost
SRMOTORSPORTS AND GREDDY MAKE SOME I BELIEVE. SORRY FOR THE ALL CAPS. MY BUTTON IS STUCK.

Posted: Sat Mar 15, 2008 9:14
by icon
i have the unorthodox pulleys. car revs faster with them

Posted: Wed Mar 19, 2008 9:14
by Buffalo
If i remember correctly you said that the only problem you have had with them is heater not heating the best every once in a while?