S13 Curtis

iTrader: (5)

looking good. i like the second rail idea. What are you using to turn on the second fuel cell pump?

94AWDcoupe

iTrader: (125)

Just an update. Had some other things pop up that took all of my free time. Still using the setup with two injectors. car is daily driven. still working perfectly as of today. No new gremlins or issues to speak of.

94AWDcoupe

iTrader: (125)

and still perfect. no adjustments as of today.

ExViTermini

iTrader: (25)

Are you still using an injector controller that is mimicking primary IDC? And you have the fuel pump setup to come online at 2psi, and injection starts after 5 psi, so you are using two hobbs switches?

94AWDcoupe

iTrader: (125)

I am only using one hobbs switch to trigger the two relays. One relay runs the fuel pump. The hella relay drives the injectors. The hobbs triggers at 5psi. I would have to look at my map to see where the trigger is concerning load lines. Tune wise its impossible to get the transition A/F perfect. The ecu averages neighboring cell values. So at the point where you tell ecu to go leaner (5psi) the next lowest load line will be effected as well so the curve goes lean for a split second. Driving the car I cant tell. The transition is seemless. in the dyno graph you can see during spoolup right were it heads lean (hump at 3400rpm)

ExViTermini

iTrader: (25)

Thanks for the reply

That power curve looks fun!!!

So are you using the relay for static injector control or are you still utilizing the injector controller?

94AWDcoupe

iTrader: (125)

the hella relay gets signal from the injectors and drives the two alky inectors. so the alky injectors fire at same duty cycle as the primaries.

ExViTermini

iTrader: (25)

That sounds pretty good, I wonder what the latency is in the relay though, at least it's not critical there.

Do you have any info on the relay itself? I assume it's the heatsinked one mounted on the frame rail?

211Ratsbud

iTrader: (1)

Deleted off base

Would it make sense to use the Hobbs switch to turn the relay on, which allows continuity for the secondaries?

Instead of firing the relay every time?

ExViTermini

iTrader: (25)

One relay powers up the pump and injectors, while the other (iassume its grounding...could be powering) is triggered cyclically by the primary injector pulse to control the secondaries. Now that I think about it...I wonder how the current load to trigger the relay coil effects the injector(s) that it's triggered off of...Im not sure it's significant enough tho...

94AWDcoupe

iTrader: (125)

The hella solid state relay doesnt draw any significant power from main injector pulse. The input trigger side of relay is photo optic. so its lightening fast and draws no significant power. the output side is rated at 32 amps. so it is loafing driving two or four injectors at about 1.5 amp each. I have a second more powerful car setup using four injectors using the same circuit. I only spent about 45 minutes dialing in that fuel curve you see on the dyno graph. its not really optimized at all. havent touched the tune since the setup went on.

ExViTermini

iTrader: (25)

More info on the relay Ie model number and such so I can see it

94AWDcoupe

iTrader: (125)

94AWDcoupe

iTrader: (125)

I have thought that ideally you would want to use two hobbs switches. set about 2 psi apart. turn fuel pump on first so fuel pressure on rail is always same. I know from simple tests I have done secondary rail is not maintaining any rail pressure. but when you turn system on at low psi its not so critical the a/f is sloppy at transition. It does become far more important when injecting larger amounts. my other car turns four 880s on and I am having a hell of time getting it to transition smooth.

ExViTermini

iTrader: (25)

Have you tried to turn it on at a higher psi? I used to engage meth at 15 psi, though it was 'progressive', but full started at 15 full in by 21, it was pretty smooth.