HFS-4 Q&A, application for your engine...

[watsonj0]

How much should I adjust the gain trimmer to make up for the map input for 2.5 bar?

[Richard L]

It all depends on how far you are away from full range of the MAP sensor.

We will be shipping the next batch of HFS-4 (V1.1) for 2.5 and 3.5 bar MAP sensor. If you are not in a hurry, send your controller back to me I will modify it for you at no charge as long as you pay the return shipping.

[watsonj0]

max will be 20 psi

[Richard L]

you don't need much amplication.

Is the flow going to be progressive with boost or IDC?

[watsonj0]

yes thats what we plan

[watsonj0]

I guess we are going to go with just IDC is this an issue?

[Richard L]

No issues.

With the HFS-4 you can try both trigger method. IDC is more reflective of true engine load.

[watsonj0]

we are starting to tune and intake temps are ok but I realize that we are running 2 1mm jets but have the .7 mm restrictor before the fav this seems counterintuative we need right around the 680 mm flow going by your manual. should we step up to the .9 restrictor?

[watsonj0]

here are the setup calculations I used.
From what I gather stock injectors are 575cc @ 5bar.
So 575 x 6 = 3450 cc
3450 x 15% = 517.5
3450 x 20% = 690

plus 10% for system pumping losses=
(15%) = 569
(20%) = 759

divide by two for two jets = 379.5

operating pressure is 160psi subtracting boost pressure of 1.4 bar (20.3 PSI) = 139.7

referencing the chart i come up with .9mm (M5.3) jets.

please confirm my calcs.
thanks
Jon

[watsonj0]

we can not get the fail safe relay to trigger, we currently have continuity between white and brown and are trying to trigger it so that it goes to black on failsafe and breaks the ground to a relay? any suggestions would be appreciated we have an EBC that we are trying to cut the power to upon fail safer triggering and run just waste gate pressure.