unorthadox underdrive pulleys yes or no

[m3f_96BmwCosmo_c44c0f570d]

i have a chance to get a good deal on a set of 4 pulleys do you guys have an opinion on them should i get tehm or do tehy not work well with our cars? any recomendations or help would be nice the pulleys inlcue alt, pwr str onather forgot were it goes and the lower crank shaft pulley yes or no and why if you guys wouldnt mind

[m3f_Sirius_880bd69485]

I would get the ones for the accessories, alt, power steering and waterpump. If you have a lightweight flywheel, don't do the crank pulley. Likewise, if you put the crank pully on, don't do a lightweight flywheel.



Theres been debate that the powerpully could damage your crankshaft, but theres also plenty of people on this fourm that have been running them for 30,000 miles. So *shrug*



You'll notice the car rev up faster, but you'll gain maybe 5-10hp at best with them.

When I went back to stock pullies I could feel the rev difference.

[m3f_SG_M3_d1201712b5]

The accessory pulleys don't matter, little power to be had with them.



The crank pulley is where the power is. There is no reason to worry if you have a stock flywheel.



You will gain 10 + rwhp, with a crank pulley. IMO, there is no better bang for the buck mod.

[m3f_m3fuz_1da011f372]

I thought you couldn't do the crank/accessory pulley combination, its one or the other. I have the UUC underdrive pulleys (just the water and powersteering, not the alternator) and I haven't really noticed much of a difference other than the car being more "rev-happy." As far as HP gains are concerned, I doubt that I got more than one or two.



I've heard, and am considering, switching the accessory pulleys for a crank pulley to get some real gains. I have no plans for a lightweight flywheel, so the issues with it are not there. If you do a search on the forum, you will see that this topic has been debated many times.