My HKS S/C Installation
#203
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This is the calcuation as provided to me by rotrex a few years ago. Keep in mind that there are 2 MAX speeds that you need to stay under. Max Input Shaft Speed and Max Impeller Speed
I = E x ((Dc+2.8)/(Dp+2.8)) x 9.483
I = Impeller speed max
E = Engine Speed max
Dc = Crank Pulley Diameter
Dp = S/C Pulley Diameter
The C30-94 which is what the Gen 1 SC was based on has a 100,000/10,500rpm limit
I = E x ((Dc+2.8)/(Dp+2.8)) x 9.483
I = Impeller speed max
E = Engine Speed max
Dc = Crank Pulley Diameter
Dp = S/C Pulley Diameter
The C30-94 which is what the Gen 1 SC was based on has a 100,000/10,500rpm limit
#205
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This is the calcuation as provided to me by rotrex a few years ago. Keep in mind that there are 2 MAX speeds that you need to stay under. Max Input Shaft Speed and Max Impeller Speed
I = E x ((Dc+2.8)/(Dp+2.8)) x 9.483
I = Impeller speed max
E = Engine Speed max
Dc = Crank Pulley Diameter
Dp = S/C Pulley Diameter
The C30-94 which is what the Gen 1 SC was based on has a 100,000/10,500rpm limit
I = E x ((Dc+2.8)/(Dp+2.8)) x 9.483
I = Impeller speed max
E = Engine Speed max
Dc = Crank Pulley Diameter
Dp = S/C Pulley Diameter
The C30-94 which is what the Gen 1 SC was based on has a 100,000/10,500rpm limit
What I am sure of is the following specs:
Max engine rpm: 7000
ATI Crank Pulley diameter: 6.610"
GTM SC pulley: 3.346" (85mm)
SC drive (step-up) ratio: 9.444
Using the formula you posted:
I=7000*((6.610+2.8)/(3.346+2.8))*9.444
I get a impeller speed of ~101,216 at 7k rpms. This is under the stated max limit of 110,000.
However, if I plug in the numbers into an impeller speed calculator on the net:
http://www.928motorsports.com/servic...ingpulley.html
I=(Crank pulley size / Blower pulley size x step up ratio) x max rpm
I get 130,596. That's a differnce of ~30,000 rpm and either 10,000rpm below the max limit or 20,000rpm above the limit.
Last edited by jonnylaw; 05-01-2010 at 01:13 PM.
#209
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Well got my PMAS installed and Tuned in. Dyno'ed at 369whp/336wtq with 9.4 Psi. All that was tuned with just AFR at about 11.5 from 2500 Rpm up. The Rev limiter is set at 6650. This tune is Very safe. I will be getting another tune later by another shop that has bit more experience with Z's and Osiris.
Last edited by cdoxp800; 05-02-2010 at 06:27 AM.
#210
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I'm guessing when you did your calculations, including the 2.8 for belt thickness, you were using mm instead of inches? Using the equation from Rotrex/other sites, I am over the max limit at high rpm and should change back to stock size pulley.
Now I need to decide on whether to put on a new OEM pulley or spend extra money for a Ross Metal Jacket dampened crank pulley that retains OEM diameter.
Now I need to decide on whether to put on a new OEM pulley or spend extra money for a Ross Metal Jacket dampened crank pulley that retains OEM diameter.
#212
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Last edited by cdoxp800; 05-02-2010 at 08:19 PM.
#215
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Well got my PMAS installed and Tuned in. Dyno'ed at 369whp/336wtq with 9.4 Psi. All that was tuned with just AFR at about 11.5 from 2500 Rpm up. The Rev limiter is set at 6650. This tune is Very safe. I will be getting another tune later by another shop that has bit more experience with Z's and Osiris.
#216
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Well got my PMAS installed and Tuned in. Dyno'ed at 369whp/336wtq with 9.4 Psi. All that was tuned with just AFR at about 11.5 from 2500 Rpm up. The Rev limiter is set at 6650. This tune is Very safe. I will be getting another tune later by another shop that has bit more experience with Z's and Osiris.
What other breathing mods do you have?
#217
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Just wondering, now that there are a few more HKS super chargers up and running, how are your temps going? Are they holding ok or has there been any rises. We are heading into autumn/winter down under so shouldn't be an issue short term!!!! Would be great to hear any comments and what cooling mods if any you have.
Thanks in advance and well done to ITOzann cdoxp800, kelly350Z, jonnylaw, IanP
Thanks in advance and well done to ITOzann cdoxp800, kelly350Z, jonnylaw, IanP
#218
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Nismo Cat Back
MotorDyne 5/16 ISO Spacer & Mrev 2
Unorthodox Pulley "Stock Size"
Berk Metallic Substrate High Flow Cats
HKS Gt Supercharger (GTM Stage 4)
I have not done any cooling mods. The car is running at normal operating temperatures so far. Even on the dyno doing 10 pulls, it really never got our of the range of it's normal operating temperatures.
So far I am loving the new Power. it really makes the car come alive. I am very please with the HKS unit.
MotorDyne 5/16 ISO Spacer & Mrev 2
Unorthodox Pulley "Stock Size"
Berk Metallic Substrate High Flow Cats
HKS Gt Supercharger (GTM Stage 4)
Just wondering, now that there are a few more HKS super chargers up and running, how are your temps going? Are they holding ok or has there been any rises. We are heading into autumn/winter down under so shouldn't be an issue short term!!!! Would be great to hear any comments and what cooling mods if any you have.
Thanks in advance and well done to ITOzann cdoxp800, kelly350Z, jonnylaw, IanP
Thanks in advance and well done to ITOzann cdoxp800, kelly350Z, jonnylaw, IanP
So far I am loving the new Power. it really makes the car come alive. I am very please with the HKS unit.
#219
New Member
iTrader: (2)
Just wondering, now that there are a few more HKS super chargers up and running, how are your temps going? Are they holding ok or has there been any rises. We are heading into autumn/winter down under so shouldn't be an issue short term!!!! Would be great to hear any comments and what cooling mods if any you have.
Thanks in advance and well done to ITOzann cdoxp800, kelly350Z, jonnylaw, IanP
Thanks in advance and well done to ITOzann cdoxp800, kelly350Z, jonnylaw, IanP