Under Pulley - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Johnny Danger · 08-10-2009, 05:36 PM

Does anyone have any experience using a light weight under pulley on a 986 boxster s
(e.g. Mantis Racing, BBI Tuning) ?

Jake Raby · 08-10-2009, 05:47 PM

Yes I have data from 3 different units compared to stock on 4 different engines.

The one I tested on ly 911 saturday was good for a 10HP gain at the rear wheels, on my dyno.

Johnny Danger · 08-10-2009, 05:56 PM

Quote:

Originally Posted by Jake Raby

Yes I have data from 3 different units compared to stock on 4 different engines.

The one I tested on ly 911 saturday was good for a 10HP gain at the rear wheels, on my dyno.

Who's product did you use ? And what did the install entail ? Some "tuners" in my neck of the woods have suggested that it's a more involved install than one would think.

Johnny

Jake Raby · 08-10-2009, 06:45 PM

The unit I installed this weekend was one of our products that I am gathering data from this weekend at an event.. It has not yet been released, ad it is the smallest on the market. I want to determine what temperatures I see with the coolant and power steering fluid and go from there.

The install isn't that hard.. The biggest pain is having to trim down the boss on the block that holds the engine lock, but I made a piloted end mill for this that works great in a drill and makes a 2 minute job out of it..

The other pain is holding the crank while torquing the crank pulley bolt to the specified value.

I can swap one in about 40 minutes start to finish, on a test car in about 25 minutes with the engine hot on the dyno.

"Tuners" generally aren't very good wrenches...

23109VC · 08-10-2009, 07:37 PM

would a pulley make a noticeable power gain on a 2000 2.7?

Jake Raby · 08-11-2009, 05:07 AM

Quote:

Originally Posted by 23109VC

would a pulley make a noticeable power gain on a 2000 2.7?

More than about any other bolt on that we have done so far... Certainly more than a 2K exhaust system.

Johnny Danger · 08-11-2009, 01:16 PM

Quote:

Originally Posted by Jake Raby

The unit I installed this weekend was one of our products that I am gathering data from this weekend at an event.. It has not yet been released, ad it is the smallest on the market. I want to determine what temperatures I see with the coolant and power steering fluid and go from there.

The install isn't that hard.. The biggest pain is having to trim down the boss on the block that holds the engine lock, but I made a piloted end mill for this that works great in a drill and makes a 2 minute job out of it..

The other pain is holding the crank while torquing the crank pulley bolt to the specified value.

I can swap one in about 40 minutes start to finish, on a test car in about 25 minutes with the engine hot on the dyno.

"Tuners" generally aren't very good wrenches...

If things go well this weekend, when do you think your pulley will become available ?

Jake Raby · 08-11-2009, 04:22 PM

Quote:

Originally Posted by Johnny Danger

If things go well this weekend, when do you think your pulley will become available ?

It'll take more time than that.. I want to do some studies in low speed applications with my Wife driving the car daily and monitor battery voltage and coolant temps Vs the stock arrangement.

jaykay · 09-24-2009, 06:54 PM

I am running a Mantis pulley......at the moment

Jake Raby · 09-27-2009, 08:23 AM

Our 4" version is now fully tested on the street.. After a DE, 4,500 street miles (and a lot at low speeds and in traffic with the A/C and head lights on) and coming within 1/2 of 1 MPH from a Land Speed Record the unit has proven it's self.

I've seen a minimum of 5HP gain (at the rear wheels) with this unit along with LOWER coolant and power steering fluid temps. One engine has seen 8 HP, but it was one of my high revving 3.2>>3.6 modified engines.