(sorry no pics)
Today I installed my Motostorm UDP. They are the exact same design as the UR ones and go for about $130 new (so they arent the cheapo ebay ones). The project turned out to be a little tougher and longer than I anticipated. I tried with all my might and lots of air power to remove the crank pulley bolt but couldnt do it. Finally I looked online and saw the starter trick and that worked like a charm. When putting my new one on, I wanted to comment, and this is also probly the main reason Im making this thread, that the recommended PS belt size in the FAQs was too small for me. I lowered my PS pump completely and still couldnt get the K040292 gates belt (755mm diam.) on there. I had to go to autozone and get a 760mm diam. belt and then it was all smooth sailing. I still used the K060408 for the accessory belt tho.

After getting the pulley on, I noticed my car revs a little quicker. I didnt really beat on it too much but i definately noticed it was there. It seems to have a little more pull in first and second gear (but my car already felt like it had good pull )

Also another thought. I have a radar detector that tells me my voltage. Before the install I would get a constant 14.1v from the alty, now afterwards Ive noticed I only get 13.5v at idle and 13.7-13.9 during normal driving (2000-2500rpms).

Anyways, just sharing my thoughts on my recent install. I feel it was worth it and it compliments my stillen flywheel very well.

 

My udp does that same thing. 13.5 volts is still with in spec at idle as the alternator will not put out proper voltage until something like 2000 rpms. WIth your reduced diameter of the udp (~20%) it might would reduce the voltage at idle. Not a big deal. Did you notice any difference at start-up? Mine seems to start a little easier.

2.3 hp/lb I believe is the average that you should see with this mod. People say it doesn't do much, but with mine I removed just over 4 lbs. thats good for over 8 hp.

 

I didnt notice any differences at start up, but my car usually always starts right up with no problems.

 

I noticed a little smoother revving but also a quicker decrease in revs (when not under load) when the throttle is released. The amount of "power" it frees up is equal to maybe that of atmospheric pressure changes but it all adds up...

 

The Wizard and Speedymax and I all lost 2PSI of boost when we installed our lightened (but stock diameter) crank pulleys. Not sure why?

black, when trying to get on the K040292, did you remember to loosen your adjuster pulley all the way? I've done that before - I spent 1/2 an hour struggling to get a "tight" belt on only to realize I could've loosened the adjuster pulley more. :S

 

ya not sure why you lost boost installing a stock diameter pulley. maybe the less weight and inertia of the pulley has a harder time keeping the momentum of the S/C pulley spinning.

Ya I loosened the power steering pump all the way down and it was still ridiculously tight. Using the 760mm belt I have the belt tight with the P/S pump about 1/4 from the lowest so I could have still tightened it quite a bit more. Idk, maybe the motostorm pulley isnt as 'underdrive' as the UR one. The main accessory belt, like I said tho, was the same belt as the UR pulley.

 

And that's part of the reason I took my sub out...

You don't by chance have an escort 8500 x50 radar detector, do you?

 

No, I have the Cobra XRS 9930.

 

aww...I thought we were gonna have something else in common, lol.

 

I'm not talking about the PS pulley, I'm talking about the belt tensioner pulley.

 

what does the belt tensioner pulley have to do with putting the PS belt on?

 

Nothing.

 

Oh, I thought you were talking about the serpentine belt. You are talking about the PS belt? I didn't think the UDP changed the size of the PS belt pulley diameter?? Why would you need a new size PS belt with a UDP?

 

The stock PS belt size is 775mm diam. The FAQ instructions say to use 755mm, I used 760mm.

 

Gotcha. But why did you replace the PS belt instead of using your stock belt? You needed to use a different serpintine belt, right? When I replaced my PS belt, I just told Autozone what car I have and they have it in their computer, you shouldn't need the FAQ for OEM size belts.

 

The PS belt with an UDP is smaller than with the stock pulley. The stock belt would have been too big.

 

So a UDP underdrives the PS too, huh? Do you feel a difference? Is the steering a bit tighter?

 

Yeah apparently it does...and I wondered the same thing. I felt no difference though.