I needed some custom pulleys made for a supercharger setup and after talking to a few different companies I picked Pulley Boys ( http://www.pulleyboys.com ). They own several CNC lathes and CNC mills and are very helpful. I just thought I'd share in case any of you all need to get any custom aluminum work done. Here's the first pulley that arrived today (sorry for the crappy pics, can't find my regular camera so I'm using the camera in my cell phone):


This is the new custom pulley next to a Motorvations pulley that I used to get the offsets right. It's bare now, but tomorrow I'll be dropping it off at a local place for hard anodizing.:




Crappy pic from the side:




Even crappier pic:




It cost $300 shipped, which included the CAD work and interrupting their production runs to program the machines for this one piece, not bad considering production pulleys from others cost $170. Turnaround time was one day, and the guys at Pulley Boys are very good to deal with. I've measured it and it looks like they got it exactly right dimensionally.

 

What is that for? specs if you don't mind. Jim

 

It's for a Dart-block B22 stroker, intercooled, Endyn-blower JRSC setup. It's the same specs as the MVM alternator pulley, but there are raised lips at the edges of the grooves for the belts to make it less prone to belts walking off the pulley during lapping days. Running a road course puts a lot of stress on it and the belts tend to jump tracks after a few hot laps. This coupled with a custom 3.2" blower pulley should make 10 PSI. We (JDogg and I) made a little over 300 WHP at 8 PSI, and that was before I got better cams, some headwork, and a custom header, so hopefully it will make 325-350 WHP when I get it back to the dyno.

 

I guess he realized it was for the alternator, my crank is babied with a Fluidampr pulley

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rmcdaniels &raquo;</TD></TR><TR><TD CLASS="quote">I guess he realized it was for the alternator, my crank is babied with a Fluidampr pulley </TD></TR></TABLE>

Yeah, I spoke too soon. Good luck with your quest!

 

found my camera, better pics:

 

wait is that a pulley for the supercharger or the crank pulley? looks to small to be useful for a crank pulley...

wow you have 2.2 liters on a b series engine?

 

It's for the alternator. The S/C gets spun off the new alternator pulley.

 

oh i see.... ok ya that makes sense cause it would be positioned closer to the supercharger..... but why not make the pulley larger?

well actually too much psi gets expensive in parts and gas.... maybe in the future..

 

It's 2.156L, 95mm crank with an 85mm bore and 5.967" rods, -2cc pistons and a 38cc GSR head.

The supercharger can only push so much lb/min of air, so running too much boost will ruin it's efficiency and overheat the blower It's eventually going into a completely stripped EG hatch for road racing and autox (it's in my EM1 DD now), so 325-350 WHP should be plenty.

 

BTW, I have a new prototype big tube header that would probably work well on your set up. I think it's too big for most NA cars.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SMSP &raquo;</TD></TR><TR><TD CLASS="quote">BTW, I have a new prototype big tube header that would probably work well on your set up. I think it's too big for most NA cars.</TD></TR></TABLE>

That sounds interesting. Currently I've got a homemade (except for the merge collector) big/short primary header with a 3" collector. It wasn't made by anyone with any header experience, I just wanted to get something big and unrestricted on it. We made a bit over 300 WHP at RLZ with an RMF narrow header (my old N/A header), but we (and Randy) figured that the &lt;2" collector on that piece was not the best for this application, so I got rid of it.

It would be interesting to get something on the car that's suited to this application and made by somebody who really knows what they're doing with headers. Please let me know what we can do to get a prototype on the car. I'll probably be ready for final dyno tuning in a couple of weeks (hydro-locked it last week in the flooding here in Raleigh, so there's a few rods/bearings to be replaced) and I'd love to have a good header to put on it.

Here's some pics of the homemade header that's on it now:

 

Forgot to check back in this thread. That's a serious project and good idea on the taller lip. Belt walk is big issue as back to back pulls come into play. Killer project man.