Thanks Jonny! Should be the same on the zed, but would appreciate if someone can confirm this.

Cheers,
Ian

 

The Gen 1 HKS SC had the MAF plugged into the cast HKS intake pipe from memory

 

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

 

Thanks Mike! That pretty much confirms it!

 

By max input speed, I assume this is engine rpm? With the HKS GTS7040 SC, the drive ratio is 9.444, and the max limit is 110,000 rpm. I'm a little confused over what my calculated impeller speed is with my current setup (various online caluculators/formulas have yielded different results).

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.

 

This is a screen shot from the Rotrex general installation guide. The 2.8mm is not in this formula but I assume this is the estimated belt thickness. It is up to you which formula to believe but i'm trying to give as much info to u to make an educated guess

 

FWIW he's adding 2.8 inches, not mm in his equation above.

do you know what that 2.8" is for?

Otherwise the rotrex equation that Rizk posted has you at 131000 rpms, same you you calc'd

 

^^^^ I would assume the belt thickness.

 

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.

 

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.

 

Hey Guys,

I'm wanting to purchase T-Clamps to replace the worm drive clamps. on the intake and intercooler piping.

Does anyone know the diameter of said piping?

 

Intake:
3"
2.5"

Intercooler:
2.5"


I ordered from http://www.siliconeintakes.com/

 

thanks dude! Why did you modify the amounts of each clamps that you purchased?

That was handy info.

 

Some places where just to space limiting to fit the t-bolt clamps.

 

What are you power/breathing mods?

 

Nice numbers. I can't find anyone that tunes Fcons here in Toronto, or in the nearby area. I will get mine tuned also with osiris and get bigger injectors and fuel pump.

What other breathing mods do you have?

 

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

 

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.

 

Should be getting my car back on Monday so will let you know how temps are effected as I have a 4hour trip home from my tuner which should be plenty to find out. Only additional cooling mods is a 54mm radiator, I also have an oil cooler ready to go on once I get the hardware for the oil pan spacer

 

I run an ARC radiator and an ARC 1 qrt extra capacity oil pan. No engine oil cooler for the moment.