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Blackstar
22-04-2011, 07:34 PM
What can be done with a billet of aluminium?

Beautiful workmanship right here in Geelong.

http://img810.imageshack.us/img810/1350/3pulleysforsprintex.jpg (http://img810.imageshack.us/i/3pulleysforsprintex.jpg/)

Fitted the 65mm pulley today...12 psi.

.

flyboy
22-04-2011, 09:22 PM
Nice.

Foozrcool
23-04-2011, 05:27 AM
Have you confirmed the 12PSI boost via a gauge? The Sprintex calculator isn't very accurate.

What boost do you thing the 74 & 70mm will net?

SAVAGE ³
23-04-2011, 05:54 AM
How much did they cost to get machined? And could you put me in contact with the mob that made them. Keen on a 74, 72 or a 70mm pulley.

Blackstar
23-04-2011, 09:58 AM
Have you confirmed the 12PSI boost via a gauge? The Sprintex calculator isn't very accurate.

What boost do you think the 74 & 70mm will net?

Nah...didn't use their calculator, used some maths to arrive at some most likely pulley sizes.

My Ecudatascan device says it's 10 psi at 5000 rpm...so with about 1000rpm to go I believe my maths is either spot on or a bit conservative.

The pulleys were made by the very talented guy that's fabricating my K-frame and rear axle for the AWD conversion.

He made them straight from the Sprintex PDF that I emailed him.

The Sprintex blower neck has two models, the first one (supplied by sprintex) didn't fit, so that's why I had them custom made.

It's a simple mod to make it fit but you need some good tools.


We all know that when you change the pulley the belt size changes...eh?

I was going to try one pulley at a time, the stock belt is 2400mm so bought two 6PK belts from Repco but the 2365mm is way too small...the 2475mm is the one to get....$47 plus GST...(pretty cheap really)

The 74mm pulley, I reckon will get about 8 psi, the 70 mm I reckon about 10 psi....at 6250 rpm.

Of course that's at redline...and what idiot drives at redline all the time...lol

For me...the whole torque band has moved significantly down the rev range...

I had to fit the 65mm first up cause I only had the two belts and Repco was shut....so will leave it at 65mm.

65mm is the smallest pulley that you can fit to the S5-335 without machining the extension neck.
Getting the pulley off is a feat of patience...make sure the engine is nice and warmed up cause the pulley is aluminium and the shim spacer is steel and they have different expansion coefficients.
Also...you need to make a large version of an angle grinder disk tool (plate with two dowels).

Fooz, If you want either of those pulleys or both, you can have them for free, but you have a 50% chance that you'll need to lightly machine them to get them to fit....depending what neck profile your blower has.

Consider that as my "thank you" for organizing the KSP brakes for me and others.

Blackstar
23-04-2011, 10:07 AM
How much did they cost to get machined? And could you put me in contact with the mob that made them. Keen on a 74, 72 or a 70mm pulley.


Normally $220 for each pulley.

Dingers
23-04-2011, 10:25 AM
Blackstar banned in the last 20mins? Wonder what happened.

Being a SC noob, is it the smaller the pulley or bigger for more power?

Disciple
23-04-2011, 10:30 AM
Smaller.