# belt/pulley question



## EvilPotato (Sep 6, 2005)

i have an Unorthodox underdrive crank pulley still sittin around cause i can't find the belts they recommend to use. Will my stock belts work?


----------



## psuLemon (Apr 23, 2003)

EvilPotato said:


> i have an Unorthodox underdrive crank pulley still sittin around cause i can't find the belts they recommend to use. Will my stock belts work?


http://www.nissanperformancemag.com/january02/ur.shtml

stocks wont work.. look at the bottom of that page


----------



## skootz1 (Oct 12, 2005)

If you used the stock diameter pulleys you should be fine. But it appears as if you got the other ones that UR ofers.


----------



## psuLemon (Apr 23, 2003)

skootz1 said:


> If you used the stock diameter pulleys you should be fine. But it appears as if you got the other ones that UR ofers.


you should not be using the stock belts if you have the UR pulley on as the stock pulley and the UR pulley are two different sizes. Get the ones that i suggested if you want a good fit.


----------



## skootz1 (Oct 12, 2005)

thats good shit. i have to remeber that. I plan on doing the same thing to my car. I didnt read anything that said i would need different belts. I thought the stock diameter pulleys were just lighter.


----------



## psuLemon (Apr 23, 2003)

skootz1 said:


> thats good shit. i have to remeber that. I plan on doing the same thing to my car. I didnt read anything that said i would need different belts. I thought the stock diameter pulleys were just lighter.


you actually might want to look at the pictures in the link i posted, and then also check out www.sentra.net;)


----------



## skootz1 (Oct 12, 2005)

I checked out the site and i read the article on pulleys. It didnt refer to any type of belt. It didnt even mention any belts?


----------



## psuLemon (Apr 23, 2003)

skootz1 said:


> I checked out the site and i read the article on pulleys. It didnt refer to any type of belt. It didnt even mention any belts?


thats funny, cuz i would have thought the "BELTS NEEDED" section was a dead give-a-way on the NPM article.


----------



## skootz1 (Oct 12, 2005)

in the article it self it didnt say anything about belts. The link you gave me said nothing.

Unorthodox Racing Underdrive Pulleys
[Back to Top]


The Unorthodox Racing Underdrive pulley is good for a few free hp with no negative side effects. It is CNC machined form lightweight aluminum eliminating a few lbs of rotating mass from the crank, making the car rev more easily. It is a worthy bolt on mod and relatively inexpensive. 
Being skeptical of the claims for big horsepower on the Unorthodox Racing web site, we ordered up their underdrive pulley to do some dyno testing. When received, the pulley was obviously CNC machined from billet aluminum and anodized a nice shade of red. It was significantly lighter than the stock pulley. We measured the TDC mark in relation to the keyway to make sure that the TDC mark was right on. It was. 

To install the pulley, we removed the passenger side wheel and wheelwell splash shield, exposing the front of the engine. An air impact was then used to remove the main pulley nut. A puller was used to remove the stock pulley. 

After running the car, our SOTP estimate of power gain was moderate, about 2-4 hp. The engine felt more eager to rev and there was less drag when the AC compressor kicked on.

We plugged in a CONSULT to test for charging function and overheating. The battery output stayed above 12 volts with all electrical accessories going full blast. We tried to make the car overheat in bumper to bumper traffic, plus extended high speed cruising. The coolant temp never went above 94 degrees C. We also did some violent slalom maneuvers to test the power steering. There was no sign of power steering pump up. The AC was perhaps a little less effective but it was hardly noticeable. After all this testing I conclude that the pulleys are at least safe. 

Some list members have been concerned that the underdrive pulleys lack of an inertia ring as the one in the stock pulley could have some negative effects on motor life. We believe that this is not true. The GA16DE, unlike most domestic motors, is internally balanced. It does not rely on a counterweight on the front pulley and flywheel to give dynamic balance like Ford or Chevy engines. Highly modified domestic motors are internally balanced at a great cost but us Nissan owners get that stock! We believe that the damper on the stock pulley is mostly to damp out accessory drive noise. With the underdrive pulley in place there actually seems to be less idle and high rpm vibration. We could not detect any increase in accessory drive noise.

On the dyno the pulley gave us 1 more peak hp but 3-4 through the often used midrange. We think we proved that the pulley does not harm anything. Overall the pulley is a pretty decent gain for the low price of this mod and gets the nod as a good bang for the buck from us.


----------



## psuLemon (Apr 23, 2003)

NPM said:


> Belts Needed
> 
> 
> 
> ...



are you sure.. cuz i see it plain as day


----------



## Hendrix (Jan 17, 2004)

Edit: beat me to it by 3 minutes



NissanPowerMagazine said:


> We recommend using Gates Belts
> 
> Sentra/200SX GA16DE
> 
> ...


just because I was feeling nice


----------



## skootz1 (Oct 12, 2005)

what is the site you got that from?


----------



## skootz1 (Oct 12, 2005)

psuLemon said:


> you actually might want to look at the pictures in the link i posted, and then also check out www.sentra.net;)


Its not on that site, its on 

http://www.nissanperformancemag.com/january02/ur.shtml


----------



## huskya83 (Apr 20, 2004)

correct, I was going to do the same upgrade but I don't know how hard the belts will be, to be taken off. Plus there's the concern of the puller tool to take off the belts, if that is needed.

Let me know the overall time it takes you to get the process done


----------



## psuLemon (Apr 23, 2003)

huskya83 said:


> correct, I was going to do the same upgrade but I don't know how hard the belts will be, to be taken off. Plus there's the concern of the puller tool to take off the belts, if that is needed.
> 
> Let me know the overall time it takes you to get the process done


belts are easy, this process tkes bout 30 minutes to an hour, very easy to do, its best to have a freind to help.


----------



## wildmanee (Nov 21, 2004)

Finding the bolt on the water pump is a huge bitch, however. First time is probably not going to take you 30 minutes to an hour, unless you know what you are going to be doing exactly. 

This'll prolly help:

http://www.nissanforums.com/showpost.php?p=936931&postcount=33


----------



## wildmanee (Nov 21, 2004)

psuLemon said:


> http://www.nissanperformancemag.com/january02/ur.shtml
> 
> stocks wont work.. look at the bottom of that page


And for those who didn't find the correct belt sizes... open your eyes, and read what psuLemon originally posted. Skootz, the link to the article with the belt size information was the FIRST LINK lemon posted.


----------



## psuLemon (Apr 23, 2003)

i did the UR pulley in like 45 minutes and it was my first time. If you want to change the Front main seal like wildmane said, it might be a good idea. then it would take you a few extra minutes/hours. The UR pulley is very easy to put on (in my opinion). The belts are easy, just need to locate the two tension screws to loosen the belts, just dont over loosen or they will come out and is a bish to put back in.


----------



## SentraThis96 (Nov 14, 2009)

Do you think the Gates K040310 Gates K060425 are the same for the OBX Underdrive pulley? Couldn't find a UR for my GA16 so i went ahead and bought an OBX. I know one difference between the two pulleys is that the OBX doesn't have timing marks but i'm not sure if it is the same size or not. LET ME KNOW! Thanks


----------

