Anyone using the RSS underdrive pulley?
Rennlist Member
Joined: Jan 2008
Posts: 766
Likes: 55
From: Las Vegas, Nevada
No real reason - Internet search had them high on the list, web site was easy to navigate and price was the same. After I placed the order they told me that RSS was backlogged on production so they would be out of stock for 2-3 weeks. Might not have been the case if I had gone direct but I'm not in any great rush so was willing to wait.
My friend runs RSS that is why I was curious. Interested to know your thoughts on the pulley after install..
Banned
Joined: Mar 2010
Posts: 7,697
Likes: 32
From: Chicago
RSS is nice as it comes with a lock wrench. I have the Mantis so I made my own. Either way stay away from the really lightweight ones with spokes that have holes in them instead of being a solid surface as those have known to break.
Rennlist Member
Joined: Dec 2013
Posts: 2,325
Likes: 758
From: Santa Cruz - Norcal
The RSS version looks to be slightly larger then the rest of the pulleys on the market. They claim you can use the stock belt. I went with a 4" from Precision chassis works which came with a shorter belt, I just need to fab a tool (unless someone will lend me theirs) 
Burning Brakes
Joined: Jun 2012
Posts: 971
Likes: 18
From: Glendale CA
Tnx FLY996
So basically the RSS pulley is about a little over an inch smaller then our original one which makes it spin at an faster RPM.
For some reason I always thought people go bigger on the U/D pulley.
So basically the RSS pulley is about a little over an inch smaller then our original one which makes it spin at an faster RPM.
For some reason I always thought people go bigger on the U/D pulley.
Racer
Joined: May 2012
Posts: 256
Likes: 3
Holding RPM constant, the farther the distance from the axis the higher the linear (tangential) velocity will be (re: belt speed). So an under-drive pulley which is smaller in diameter slows the belt speed down versus a stock pulley at any given pulley/engine RPM. That's as good as I can explain it so many years out of trigonometry classes. 
Racer
Joined: May 2012
Posts: 256
Likes: 3
Do you have to relieve some material from the engine case to fit this smaller pulley? I thought I read that somewhere... some owners may prefer not to modify in fear of destroying the long term appreciation expected from these future classic Porsches!
Last edited by Viper6; May 17, 2014 at 12:44 PM. Reason: spelling
Rennlist Stories
The Best Porsche Posts for Porsche Enthusiasts
Porsche's Top 5 Most Questionable Naming Decisions
Verdad Gallardo
Pogea Racing's 964 Porsche 911 Reimagination Stands Out in a Crowded Field
Verdad Gallardo
6 Convertible Top MYTHS Most People Don't Understand!
Michael S. Palmer
2026 Porsche 911 Club Coupe is Spectacular, And Everything Wrong with the Porsche Market
Joe Kucinski
Talos Takes Your 991 Porsche 911 GT3 to the Next Level for a Cool $1.13 Million
Verdad Gallardo
9 Vehicles Porsche Helped Engineer that Aren't Porsches
Verdad Gallardo
9 Features and Characteristics That Only Porsche People Understand
Verdad Gallardo
I've Written 500 Rennlist Articles: Here's How Porsche Has Changed Along the Way
Joe Kucinski
10 Most Unnecessary Porsches Ever Built (And Why We Love Them)
Verdad Gallardo
Advanced
Joined: Aug 2012
Posts: 61
Likes: 8
From: Brunswick, GA
Yes, there is a small boss that sticks out from the back of the engine case. Due to the smaller diameter of the pulley it will hit this protrusion so you have to cut off a small amount.
Pro
Joined: Nov 2010
Posts: 745
Likes: 17
From: North york
Finally installed the RSS pulley that's been sitting around since last year.
Also installed a new oem belt, original size.
install went well, only one rookie moment....hint, car out of gear before you spin the pulley for TDC....
Also installed a new oem belt, original size.
install went well, only one rookie moment....hint, car out of gear before you spin the pulley for TDC....
Pro
Joined: Nov 2010
Posts: 745
Likes: 17
From: North york
Racer
Joined: Aug 2020
Posts: 326
Likes: 136
Resurrecting old thread just wanted to share that you can get RSS Torque solutions for $172 after using military discount at
https://www.rallysportdirect.com/pro...lley-kit-w-a-c
go to first to verify veteran status
https://www.rallysportdirect.com/cou...iscounts-codes
copy and paste code at the last page of checkout. Won’t work in the initial check out page.
*incorrectly stated RSS*
https://www.rallysportdirect.com/pro...lley-kit-w-a-c
go to first to verify veteran status
https://www.rallysportdirect.com/cou...iscounts-codes
copy and paste code at the last page of checkout. Won’t work in the initial check out page.
*incorrectly stated RSS*
Last edited by Carlo D; Aug 11, 2024 at 01:12 AM.
