Custom VEMS Output for VVT, how?

[laine_16v]

HI, after using VEMS last year on my engine, i sadly destroyed it after sucking in a bolt. but im back!

I have a clio 172 engine which i am throttle bodying.

This engine has a VVT phase shift on the inlet cam.

Solenoid voltage = 0v then Phase is set to 0 degrees.

Solenoid voltage = 12v then Phase is advanced 16 degrees on inlet cam (power mode).

I need to figure out how to use an output from vems (from P259 chip?).

So it can follow this pattern....activated at 1300rpm and de-activated at 6500rpm



I understand VEMS to can activate outputs at a certain RPM very easily, however what then about deactivating them when it reaches at certain rpm (as i want), i cant figure it out?

Im running a VEMS v3.3 prebuilt unit and it is the 1.0.73 firmware i think, should i update this? im very out of touch with VEMS. thanks.

[rob@vems.co.uk]

First things first, what resistance is the VVT solenoid?
Its simple to control (I've done it on a number of cars) you just use one of the Misc Triggers in the Extras Menu.

[laine_16v]

Ok had to wait for my mate to test his on his engine as i dont have a multimeter, but aparently its 8.8Ohms, which im guessing is not good because it will exceed the 350mA output of the P259 :/

So he suggested a darlington pair circuit ?

[gunni]

Or use a injector / ignition output?

[laine_16v]

Or use a injector / ignition output?

Thank you! Told you i was pretty thick when it comes to VEM's i shall drive it from one of those, thank you

[laine_16v]

Question: OK ill power it from INJFET (Injector Drivers), im given a choice of channels 1 - 7 and i1 - i7. But, which channel corresponds to which pin out on the Plug diagram.

I.e there is Injector Channel 1, 2, 4, 8, 16, 32 e.t.c

[rob@vems.co.uk]

The channels are shown on the pin-out, EC36-pin6 is Inj channel 64, EC36-pin7 is Inj channel 1 etc.
The choice you have is of which location in the h[0] list (Settings->Injector Outputs).

[laine_16v]

OK brilliant thanks rob i understand that One last question, the difference between channel 1 and i1, would be?

[gunni]

i means inverted. I.e normal close circuit.

[laine_16v]

i means inverted. I.e normal close circuit.

Does make sense to me, i can build a wiring loom from scratch, but i dont know what that means lol! For my purpose, do i use I or not? solenoid will get a constant 12v feed, and be negatively switched via INJFET, is that inverted or not? THanks.

[gunni]

you do not use "i"

the "i" is when you want to turn stuff off at specific points instead of turning it on.

[laine_16v]

Sorry to drag this topic back up.

I have just got the engine working on VEMS, its working very nice just as it did on my old engine so im very pleased. Just want to clarify.

I have wired the VVT soleoind's switched earth into Ignition output 30 (Pin 36). Which "Output Channel Selector" do i choose?

Its obviously not the INFJET (not wired into injecter FET's afterall), neither P259 e.t.c Is it SPECFET or I259? i dont know

Also i want this solenoid to be actiavted purely by RPM, not by throttle position or manifold pressure. So what do i put the Throttle position and Manifold pressure minimum and maximum values to?

Thanks for your continued help.

[gunni]

I259 channel 3

then put 0 as min kpa and 510 as max kpa and 0 % throttle and 100% throttle