Here is the low down-
I would like to install the underdrive pulley but I'm not sure if its going to be worth it. On the website it advertises, "The power gained by speeding up the crankshaft revolution (plus 7-10 horsepower)." I have trouble believing this because this is a lot of hp gain for a little cheap part. I understand that this will reduce the weight in rotating and reciprocating parts. As well as reduce parasitic drag along the drive train. It can reduce the inertial energy loss from the crankshaft as well. This all sounds too good. So would I gain more like 1-2hp as well as have almost no power stering and audio? Thanks-

 

Your gains to the wheels will be 1-3hp. And no, your power steering and 'audio' will not just... stop working, as you say.

 

Actually, Underdriven pulleys refer to the process of gaining horsepower by not spinning the the power steering pump and the alternator as fast as normal. Generally it can be done at either the mentioned components, or at the crank pulley. If you do a lot of slow speed driving and idling, I wouldn't suggest doing both. (The alternator may not charge sufficiently, and the steering efford may increase while parking).
It's true; the gains are there, it's a practice well established, but not as much as one would think.
That's because the real horsepower hog is the waterpump, which unfortunately is driven by the timing belt. (Try underdriving THAT!!! )

They do look nice, however, all anodized and all

P

 

most of your time will be spend trying to break loose the underdrive pulley bolt unless u have a compressor

 

Underdrive pulley bolt for my 94 = righty loosey, lefty tighty.

Also equals de suxor.

Oh yeah, I do have an AROspeed underdrive pulley (helluva difference mainly in how fast RPM's raise and drop) and I also underdrove my power steering. So the alternator is underdriven by 1 and the P/S is under driven by 2. Lights dim at low RPM so I don't underdrive the alt anymore. Trying to get rid of the P/S though. I had another car without P/S and it was fine. This one sucks without the belt.

 

[quote]
"Underdrive pulley bolt for my 94 = righty loosey, lefty tighty." [unquote]

Try saying that in Japanese !!!

P