The car is a 97 RS with a built bottom end and HRC Stage 2 Kit. It is using a Vortech S-FMU, AFC, and RC 440cc injectors. I have read that using a 2:1 ratio disk in the SFMU and using a static fuel pressure of 40 psi (idle at 26 psi) will yield the ability to boost 15 psi. Of course the AFC will be leaning out the system under vacuum and 0 boost. Now for the questions......

There are two springs in the SFMU kit. A metallic long spring about 7 coils, and a shorter gray spring that is only 4 coils. Currently the longer spring is installed. Which is the correct spring to use?

There are a bunch of discs and rings in the SFMU kit. A small (2 inch), medium (2.5 inch), and large (3 inch), plus a super large disc that I assume to be the 12:1 ratio disc. Currently the medium (2.5 inch) disc is installed with the matching medium sized ring. Which one is the correct disc for a 2:1 ratio?

The current fuel setup shows 40psi FP with the vacuum line of the SFMU unplugged. At idle (with everything hooked up) the FP is at 26psi. The AFC is currently set to around -14% at low throttle. The car is running a max of 8psi of boost at which the FP peaks at 55 to 58psi. The car runs good for 8psi of boost, but it needs to run 15psi of boost. I am trying to use the equations on Corbins web page and I am getting a little confused. First I need to make sure that the right parts are installed in the SFMU so I can then go ahead and tune it. Corbins example shows 370cc injectors which somehow yield an appox. injector size of 445cc, etc. I could use a little more description on how this works as I am a little lost. Hopefully one day I can be an expert tuner.

-Jared

Iceman CAI | RS*R Cat-Back | AFX Pully | Milled Head 10:1 CR | MP 60mm TB

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Iceman CAI | RS*R Cat-Back | AFX Pully | Milled Head 10:1 CR | MP 60mm TB