Using the UR underdrive pully kit without the airpump
 

I am using the complete UR underdrive pully kit on a single turboengine without the airpump. After getting a belt that fits the main pully to alternator I nothiced that the water pump pully is barly making contact with the belt. Has anyone one else run this setup and are you having problems with the belt slipping on the water pump pully. I am thinking that I may need to fabricate a idler pully to put tension on the water pump.
https://www.rx7club.com/attachment.p...d=184798&stc=1

I was thinking of making an idler pully and installing it here.
https://www.rx7club.com/attachment.p...d=184799&stc=1

Try to buy an electric water pump, I think that that is the correct solution , a litle bit expencier but better

I had similar issues back in the day with the UO kit. I also had problems with the underdriven alternator. Re-Install a stock aternator pulley. It will solve the contact issues with the belt as well as increase the electrical output of your alternator back to stock. The underdriven alternator will provide negligible gains on a single turbo car, maybe even stock. Fabbing an idler/tensioner pulley will be a waste of time and only clutter your engine bay.

Electric waterpump? LoL. All that money and time fabbing up new things to avoid putting the stock sized alternator pulley back on. Get real!

Yep , i think that you R rigth, more easy to turn back to the standar alternator pulley , and no more problems at nigth with the maing lamp turned on and at idle.

Thanks for the advice, I'll put the other alt. pully on tomarrow and see how that works. Now I have figure out a new belt size.

I run the UR main pulley without the alternator pulley and no ps/ac, and it works fine. If you want to keep the UR alternator pulley you could fabricate a new alternator bracket that moves the alternator a little more to the pass side to give greater contact. Good luck

I have the UR kit but use a Greedy W/P pulley to get contact area. Be warned that this make the water pump double underdriven but no problems here in 3 yrs/25K mi using Evans NPG+.

Let me know if you need the p/n for the belt that works with this arrangement.

Although if you can make an idler pulley yourself, that would be the way to go.

Jack

I had the same concern, so I purchased a pulley kit from pineapple racing. The pulley fits to the lower left of the water pump (if you are looking at your engine from the front).

I am sure you can contact Pineapple racing for more info. I would send you pics, but my computer at home is still packed up (just moved). If you really wants pics, I could send you a couple of pics with my camera phone. If you want pics, just pm me your email address and I will shoot you some photos.

Charlie

I had the same issue but Blake had a group buy on the Pineapple Racing Idler Pulley Kit so I went with it: http://www.pineappleracing.com/ProdSvcs1.html (bottom left image on page). Works great!

http://www.encompass-tech.com/photog...dlerPulley.jpg

You can see it right behind and to the left of the yellow coolant hose (sorry about the lack of focus). The belt wraps up around the water pump pulley and back to the main pulley so it's got nice contact surface and tension.