Procharger belt size
Thread Starter
Joined: Apr 2007
Posts: 843
Likes: 69
From: Rochester, MN
Procharger belt size I am currently in the process of transitioning from a D1SC to an F1A head unit. I have worked with Bob @ Brute Speed to get that on order. I am currently waiting for the head unit to show up but trying to finalize my build to keep the downtime to a minimum.
My last item in question is the size of the belt for the setup. I have a stock bottom LS1 and I am going to do my best to keep that alive with the F1A (good luck huh!). I have ordered a 5.25" pulley and have looked at the following chart from Bob's website:
http://shop.brutespeed.com/ATI-DPxxx...-ATI-DPxxx.htm
It appears I would run a 42.7" belt if I were running a standard 7.65" crank pulley. I am currently running the 7.25" SDCE crank pulley.
A simple calculation to find the difference is size is the following:
(7.65-7.25) * Pi (3.14) = 1.25"
I am assuming I would need to run the 41.5" belt based on my pulley sizes.
Is there anybody out there with a similar setup to verify this?
I also sent a note to SDCE to see if they can help out.
Thank you for your help.
My last item in question is the size of the belt for the setup. I have a stock bottom LS1 and I am going to do my best to keep that alive with the F1A (good luck huh!). I have ordered a 5.25" pulley and have looked at the following chart from Bob's website:
http://shop.brutespeed.com/ATI-DPxxx...-ATI-DPxxx.htm
It appears I would run a 42.7" belt if I were running a standard 7.65" crank pulley. I am currently running the 7.25" SDCE crank pulley.
A simple calculation to find the difference is size is the following:
(7.65-7.25) * Pi (3.14) = 1.25"
I am assuming I would need to run the 41.5" belt based on my pulley sizes.
Is there anybody out there with a similar setup to verify this?
I also sent a note to SDCE to see if they can help out.
Thank you for your help.
Is their anyone with an SCDE system on here that can offer any assistance? Thanks. Bob
__________________
ATI ProCharger and Moser Sales 260 672-2076
PM's disabled, please e-mail me
E-mail: brutespeed@gmail.comob@brutespeed.com
https://brutespeed.com/ Link to website
ATI ProCharger and Moser Sales 260 672-2076
PM's disabled, please e-mail me
E-mail: brutespeed@gmail.comob@brutespeed.com
https://brutespeed.com/ Link to website
8 sec potential, 12 sec slip
iTrader: (50)
Joined: Apr 2002
Posts: 4,092
Likes: 2
From: Savannah, GA
(Disclaimer* I'm assuming you are just using the SDCE crank pulley, not the full SDCE spring tensioner setup)
I can tell you that your calculation method is not correct. First, you would need to know what the belt wrap around the crank pulley is for that setup. The formula for arc length is S=r*θ where S= arc length, r= radius, and θ= the angle (in radians) of the circle. Your formula essentially calculates the total arc length of 100% belt wrap on a .4” diameter pulley. Knowing the circumference of a 0.4” pulley is entirely worthless to you in this situation. Secondly, I can guarantee you that you will not have 360° (or 2 pi) of belt wrap of the crank pulley.
You could try to find a picture of a setup with a big head unit pulley and try to measure the amount of wrap on the crank pulley. You could do that with a protractor relatively easy. But for example, if it has 200° of belt wrap, arc length would = (7.25/2) * (200 * (pi/180)) = 12.65. Do that again for the 7.65 pulley (13.35) and then subtract the results (13.35-12.65 = 0.7) and that will be the difference in belt size. Of course, this will be off a little since the amount of belt wrap would also vary due to diameter of the crank pulley. So this is not an exact method, but it will at least get you in the ballpark.
You can always just get everything setup and then run a string around the whole setup then measure the string to get close too.
I can tell you that your calculation method is not correct. First, you would need to know what the belt wrap around the crank pulley is for that setup. The formula for arc length is S=r*θ where S= arc length, r= radius, and θ= the angle (in radians) of the circle. Your formula essentially calculates the total arc length of 100% belt wrap on a .4” diameter pulley. Knowing the circumference of a 0.4” pulley is entirely worthless to you in this situation. Secondly, I can guarantee you that you will not have 360° (or 2 pi) of belt wrap of the crank pulley.
You could try to find a picture of a setup with a big head unit pulley and try to measure the amount of wrap on the crank pulley. You could do that with a protractor relatively easy. But for example, if it has 200° of belt wrap, arc length would = (7.25/2) * (200 * (pi/180)) = 12.65. Do that again for the 7.65 pulley (13.35) and then subtract the results (13.35-12.65 = 0.7) and that will be the difference in belt size. Of course, this will be off a little since the amount of belt wrap would also vary due to diameter of the crank pulley. So this is not an exact method, but it will at least get you in the ballpark.
You can always just get everything setup and then run a string around the whole setup then measure the string to get close too.
