UR Lightweight Under Drive Crank Pulley: My Experience

[Sleepr24]

Hey Guys,

I recently installed a UR(Unorthodox Racing) lightweight under drive crank pulley on my 2011 3.8L Genesis and I wanted to give my impressions for anyone interested.

Install: First of all let me start by saying the pulley does not have a dampener and the engine is internally balanced just to get that out of the way. For anyone who has ever worked with a crank pulley bolt, you will know it can be a major PITA to get off. I am happy to say this was not the case with the Genesis. It was too tight to use an impact gun without removing the radiator so I used the old bump method by bracing a break bar against the engine mount bar and quickly turning the car on and off (bumping). The bolt came right off. Also, you don't need a tool to remove the pulley. After releasing the belt tension the pulley popped right off. The directions said to replace the belt with a smaller belt but the belt they suggested did not fit (about 1\2 an inch too small) so you will need to stick with the stock sized belt. Installation time took less than 15 minutes if you remove the unnecessary time it took to find out the new belt was too small.

Driving impressions: So UR suggests it takes 5-6 days of driving for the ECU to adjust to the lower rotational weight for maximum performance gains. I am not sure this is 100% accurate but I can attest that it did take about 100 miles for me to start to notice the difference. You can definitely feel the engine more while driving but nothing too harsh. I must say I am very happy with how well the engine shoots through the rev ranges as compared to before, especially at 4k+. HP\TQ gains (yes I know it does not actually add power it frees up some) are minimal but the throttle response is significantly increased. All in all, I would recommend this mod as the price to benefit ratio is much higher than what u would get from a CAI or Exhaust mod (outside of headers).

 

[Huddleston]

Thanks for the write up, this might be a good option for some gen2 guys as well that are looking for some mods.

 

[Rey]

I am intrigued with the underdrive pulley concept. I checked UR website for applications; and found none for the 3.6. So, I am puzzled. Do you have a UR part number?

Also wonder if this underdrive pulley will fit the V-8s? I suspect they may use the same crank pulley. If part numbers are the same, then they will fit.

 

[Sleepr24]

I am intrigued with the underdrive pulley concept. I checked UR website for applications; and found none for the 3.6. So, I am puzzled. Do you have a UR part number?

Also wonder if this underdrive pulley will fit the V-8s? I suspect they may use the same crank pulley. If part numbers are the same, then they will fit.

Hi, unfortunately no company makes crank pulleys (under drive or else) for the sedans. The only reason that the 3.8 sedan can use the pulleys is because it shares the exact same engine (albeit in a different orientation) as the 3.8 coupe. As it happens, the pulleys are exactly the same so they fit on the sedan as well. Unfortunately since there is no V8 coupe there are no options for the V8 sedan folks at this time. You can also get the lightweight pulleys for the water pump and the alternator which I will be trying in the coming weeks.

If you are looking for the 3.8 pulleys, you can check out all the options here http://www.khartunerz.com/Pulleys-_c_167.html. Hope that answered all of your questions.