when staging with large injectors with the PS2k is it better to use primary hold or common?

I am running 550 Pri and 1680 Sec, stage point 1.5psi primary hold. during datalog of a tuning run, I noticed that the injector duty was 107% @ 4psi at the stage point the injector duty was around 70% And the primary's should be held at 70% So I am at a loss on why the haltech is reporting 107% duty.

screen shot
http://infini-fc3s.cyberosity.com/ga...reen+00017.jpg

 

at 6500 your primaries are trying to be at 10.152ms (pri stays at staging column, but rises with rpm). at 9k on your map, your pri would be at 10.484ms. Also, 10ms sounds pretty high, so i'm not suprised your are seeing such high DC. With 550s, you may need to lower your staging bar. At 7k rpm, even at 0psi you still need a good bit of fuel (say, almost all of your 550s) to maintain AFR. I had a similar problem before putting in 4x ID1000s.


FWIW, at 7k rpm with a stock turbo, my ID1000 primaries are at 4.622ms and are at about 55-60% DC. double that for your 550s and boom.... 100+% DC.

 

I basically scraped that above map and started over from scratch. yeah looking at the amount of fuel required even at 1.5psi I need to move the staging point down lower. I had the old map super rich while I was starting to tune it.

On the way home I tunes almost all of the vacuum section of the new map. added I three load columns -0.2 0 .2 and set the 0 for staging point. I had to stop tuning today because of course it started raining.


I wounder if the FD 850 injector will fit the Cosmo primary fuel rail. I have a couple extra sets....

 

Hey Tony!
Add an extra bar right where your injectors stage. That way you can fine tune it.
Also, look at Injector Dynamics injectors. Best injectors out there by far.

 

Thanks man, I'm looking at getting some id2000's soon.

 

Here's a screen shot of my 13BT with 55cc pri and 2000cc sec. GT35R and 4" exhaust. Claudio helped me out with this setup.

Staging bar set at 2.4psi

 

could you post your map?

 

Here it is... use at your own risk! Timing trigger is setup for a Cosmo.