OT, sorry : Braineack, have you read my PM? I have problems and and your help would be essential

 

^lmao @man/boy love.

 

Another advantage would be that you can run low impedance injectors without needing resistors?

 

for seq. injection? not necessarily.

 

I thought you could only run one low impedance injector from each injector driver with the MS unless you use resistors in series with them?

 

No thats a hardware limitation, nothing to do with how many times and at what point the injectors fire, which is what sequential is all about.

To run low impedance injectors without dropping resistors, you just need an injector driver capable of PWM.

You can have sentential with or without low impedance injectors if you want. The two are not mutually exclusive.

 

its more about the power draw and grounding than anything else.

you can run low ohm injectors in batch.

 

OK, I was thinking in terms of it being an advantage of doing the sequential mod for MS specifically, but then I made the mistake of thinking this was posted in the MS specific forum too.

This is getting a bit off topic, but are you suggesting that I could run two low ohm injectors per injector driver on my MS2 DIYPNP without resistors? because my understanding was that that would require the injector drivers to sink more current than they can handle.

 

I don't think the uS card can handle 2 paired low impedance injectors.

The V3/3.57 with a MSI/II/III card can however.

Similarly the MS3X card can't handle low impendance injectors.

 

You could if you ran the P&H board. But running PWM drivers directly off the uS module will result in ground noise and flyback issues.

 

A customer of mine run low impedance injectors on the DIYPNP for several months, without knowing. He always had problems with the USB to serial converter randomly disconnecting from the PC. At some point he did burn one of them, so we found out and replaced the injectors.

 

Great thread. Can someone post pics of the sequential fuel menus in MSII and what they should be? I want to do this on both cars soon.

 

 

Thanks. Is it a good idea to upgrade to really large and or EV14 injectors over my 550RX7 injectors? Will a shorter injector opening time benefit me in any way?



You entered 375* to account for your 10% cam opening...is this back-timed or is the ECM counting 375* of rotation?

 

(Posting from my phone.)

You want larger injectors to keep. The duty cycle below 80% to be able touse the timing tables properly.

 

More like 60% DC

At WOT it's pretty unnecessary, it's quite helpful for economy at part throttle though.

Honestly if you don't have any issues currently with your injectors, then leave them. If however you're hankering after more headroom and a much improved idle quality at stoich, then hell yes upgrade.

 

First of all, i want to apologize for bringing this thread back from the grave but it seemed to have the best information about sequential injection which is relevant to my case..

So, i'm running a '91 miata with MS2 extra (by reverant). I thought i'd reconfigure the batch injection into sequential, but it did not quite go as planned..

So, i rewired the injectors according to Dimitris's instructions:

- Pin 1 (INJA) goes to cylinder 1
- Pin 2 (INJD) goes to cylinder 2
- Pin 3 (INJB) goes to cylinder 3
- Pin 4 (INJC) goes to cylinder 4

- Switch from "standard drivers" to "additional drivers" in megasquirt

Then i checked (and double checked) that each injector is only connected to the corresponding pin in the right order.

Now, the car would not start up. It fires after cranking and dies immeadiately afterwards. I did manage to get it run (barely) by pushing throttle. This caused the engine to run very lean. As soon as i release the throttle, the engine stalls.

Now, if i change back to "standard drivers" the engine runs just fine! Any ideas what might cause this behaviour?

 

did he build yours with the abillity to run seq injection?

 

Yes.. He said it supports sequential.

Edit: Reverant's customer support has been excellent. I just wouldn't want to bother him constantly since i bet he's got loads of things other things to do as well..

 

Yes, all my Enhanced MS2 provide sequential. Otto, please replace each injector with a 12V auto tester, , and using the test mode, see if you can get all 4 "injectors" to light up properly. When you test each injector, only that injector must light up and none other.