AzzHauler

iTrader: (3)

Had the idea today to keep my bigger, wrong size procharger pulley and get the MMS crank pulley, instead of sending the blower in to ati to swap pullies. Less chance of belt slip with the smae or more boost. I read MMS's website about boost #'s, but wanted to see what the people using it get with their assorted sc pullies? Thanks.

AzzHauler

iTrader: (3)

Found this on the other site incase anyone else wants to know. Quote from Mike Morgan's post:

Here is a general rule on boost with the crank pulley.
Here are the conditionals:
1. Stock displacement.
2. D1SC supercharger
3. Boost measurements at 6200RPM

4.50" pulley- 7 to 8 psi
4.38" pulley- 8 to 9 psi
4.25" pulley- 9 to 10 psi
4.10" pulley- 10 to 12 psi
4.00" pulley- 12 to 14 psi
3.85" pulley- 14 to 16 psi

If you run a P1SC then take about 2 to 3psi off these numbers.

Here is a pulley conversion from your old to new
Pulley w/ stock crank ------- Pulley with MMS crank

3.20" - 4.25"
3.40" - 4.50"
anything bigger than 3.60" with your current setup would not require a crank pulley switch if unless you want to run more boost. I believe the 3.6" pulley is a 4 to 5 psi setup.


I am also working on a new belt tensioner system for the fbody. I'll let everyone know how it works out.

frcefed98

iTrader: (16)

so my question is what s/c pulley would I use? Us high altitude guys have to run smaller pulleys to get reasonable amounts of boost. I have the 3.2in on right now to achieve 9psi. So MMS + ? to get 9psi for my altitude. I posted this question on Mike Morgans post but have recieved no response.
Not a direct question posted to you, but to anyone that might have the answer.
TIA
J

02BlueFirehawk

I have a similar question but I have a ASP underdrive crank pully.