Nitrous ignition retard control

[tom70]

I'm looking at more cheating power on my wee 20v 4age by getting NOS system. I can see the rpm and WOT activation which is really nice in the software, but is there any possibility of ignition retard or additional lookup table when it is activated?

So a maximum performance is achieved when the NOS is activated and not activated (with more ign advance).

Alternatively, I can use progressive controller but it does cost alot of money. If Vems has something in the system would be nice too.

Any advice?

[rob@vems.co.uk]

Firmware version 1.0.78 ( http://kotisivu.dnainternet.net/sakrkorh/vems/firmware_1.0.78.zip )  has the following n2o control.


  uint8_t n2o_mintps;           // minimum TPS for activation (full throttle switch)
  uint8_t n2o_minrpm;           // minimum RPM for activation (not good to add too much torque on low rpm)
  uint8_t n2o_maxrpm;           // maximum rpm, switch off n2o above this rpm (recommended to hit this before revlimiter)
  uint8_t n2o_retard;           // amount of timing retard when function activated
  uint8_t n2o_minkpa;           // minimum MAP for activation (backup for TPS signal, we dont want to activate on too low load, will cause explosion)
  uint8_t n2o_maxkpa;           // maximum MAP for activation (some people use N2O only to help turbos spool quickly)
  uint8_t n2o_input;            // input channel for activation
  uint8_t n2o_output_channel;   // output channel to activate solenoid
  uint8_t n2o_settings;  // bit0:0=disabled,1=enabled, bit1:deactivated by launch control switch - 0 = off, 1=on

But I have no idea how stable the system is - its on rc (release candidate) so you will need to download your config and tables and make sure you keep them safe with your 1.0.73 version.

[tom70]

Great, this is what I want. Cheer Rob, I will look into abit more before I install the system.

BTW mine is v1.0.53, works the wonder. 

[rob@vems.co.uk]

You'll find that you need to make a few adjustments to your tables or you'll loose your spark - check the details here: http://www.vems.co.uk/forum/index.php?topic=120.0

You'll also find that the acceleration enrichment is a hell of a lot better than 1.0.53

[Tony C]

Has this the feature to pulse the nitrous and fuel solenoids?
as mine are wizard of nos pulsoids not solenoids.

[Bat]

Hi,
Tony ... From looking at the code Rob has posted up, that'll retard the timing and give you an output to trigger your NOS controller.
Should be just the job
Cheers,
Gavin

[Tony C]

Hi Gavin,
my nitrous controller is a progressive not fixed hit,
so ideally i need the controller to start ramping up to a set gas level, before the vems retards the ignition, otherwise im losing power retarding the ignition before the gas gets going,
this is why (on another post) im trying to find out if vems will accept a trigger input to retard the ignition when the n20 control says its at set % to do so,
i run 150 bhp nitrous and dont need it to retard the ignition until its at about 75bhp of n20,
at present using a cdi ignition unit with built in retard which my nitrous controller triggers at 75bhp and then the ignition retards 6degrees, i cant let the vems control my nitrous pulsoids other wise i loose the warranty, (parts failure and engine damage)

hope this throws some light onto the probs im having.

[rob@vems.co.uk]

There is no Nitrous on input into the VEMS, and I don't think that VEMS would be able to control the Nitrous pulsoids because the software isn't there to do so.

[PeepPaadam]

Maybe anti-lag stuff with mcp3208 input can be configured to do that? And use boost solenoid DC to control the nitrous solenoid?

[Tony C]

ideally i just need the vems to retard the ignition when the n20 controller says so,
that way im still ok for my parts/failure garantee on the nitrous side of things,
and the vems can still do the fuel and ignition.

Rob any chance you could ask the techs at vems mate how i can get over this?, (i dont know them :-( )

[gunni]

What are the conditions that the NOZ operates?
You could set the vems up to assume the NOZ is on under the same conditions.

Twin config would be nice to use here I guess.

[Tony C]

the prob i have mate is warranty,
the nitropus controller pulses the solenoids as they are pulsoids,
it also starts off at a user preset level and depending on time limit set on the controller it can be selected to say start at say 25% and then ramp up to 100% over what ever time you want, it also can be set to miss first gear,

i dont want to remove this controller as its preset now to the car,

[Bat]

Hi,
Well I'd just use the code above, but leave out the output channel and use your controller as normal. Then when your controller triggers for retard the VEMs should do it
Cheers,
Gavin

[Tony C]

so something like this?



and conect my n20 controller earth retard trigger to pin 16 on the ec18 plug, (via a relay of course)