Yes, they already have the drawings for the 'OEM' SOS 5.45" pulley from my setup. They can make any size you wish. I had them make me the 6-rib crank pulley in various sizes when I was experimenting. One word of caution, once you reach 6.75" the crank pulley will get very close to the water pump pulley; so try to stay under that.

Also, no need to pay a pretty penny. I'll cost you ~$150 shipped. ASP does not overcharge

Edit: I found the pictures of my 6" ASP crank pulley.
https://www.s2ki.com/s2000/topic/979...t__p__22113690

 

99SH is right on the pulley size I bought his 6.75 and there isn't enough room to get the serpentine belt off without removing it first up side I make 9psi at 8500rpm on a 4.4'' blower pulley

 

Sweet! Thanks!

I think I will go with a 6" crank pulley as well. I just did some calculations and came up with an extra 3 or so PSI, which is exactly what I want. From my calculations running a 6"crank pulley would be the equivalent to running a 2.85" blower pulley instead of my 3.4". At that operating area it looks like SOS claims around 1psi per 0.2" blower pulley diameter increment. Thus the 3psi estimate.

99SH, You had the 6" pulley, would you say those calculations are in the ballpark? Also, whats your take regarding belt slip of a 3.4" blower pulley with a 6" crank pulley? Perhaps run a 3.6" blower pulley with a 6" crank pulley?

 

Nice!! but as i noticed in the pics you are running the novi1200 right?

 

Your calculations are correct. You'll see a ~3PSI increase going from a 5.45/3.4" pulley combo to a 6/3.4" combo

Since you already have the 3.4" pulley, give that a shot and see how your belt slip goes. You seem to be having good success on the 3.4" If you do encounter slippage, you can get a larger crank pulley, a 2nd idler pulley and/or a grooved blower pulley.

Also, one thing to note. Make sure you verify there's a belt that fits the pulley configuration you want to run. It's much easier on the 6-rib as the belts are available in many incremental sizes; this was more of an issue with my 10-rib belt. But check to make sure. I'll give you some of my links to give you a head-start.

Gates belt catalog: http://www.gates.com/oreilly/PDFs/SizeListings.pdf
Goodyear belt catalog (use the outside length measurement): http://old3.rusrek.com/en/blog/gz_jackpan/381922/
Belt calculator: http://www.calculatoredge.com/mech/vbelt%20length.htm

Use the belt calculator with your current setup and reverse engineer the pulley spacing (input your current crank & blower pulley size and play with pulley center spacing until you get the belt size you currently have - Note all units are in inches). Then change the pulley sizes to the new setup and see what new the belt length is. From there, look at the catalogs and verify there's something in the close ballpark.


Yes, Novi 1200. Same difference, as far as pulleys dimensions go.

 

Bumping this.. how are you guys calculating these numbers? I feel like it would make sense to just keep my current 3.8" pulley and get a 6-6.5" crank pulley. I'm currently making 7 -8 psi on my CT nv1000. How much more psi should I expect?

 

I've just put a 2.8" on my Novi1000 and made 14.5PSI @ 8500 and 15.5 @ 9000. No slip from 2nd onwards. There's a bit in 1st but it just goes sideways anyway ha!

I cut grooves in and used a gatorback belt.

It made 420WHP @ 8500RPM

https://www.s2ki.com/s2000/topic/112...er-novi1000-3/