Setting the ECU to 720's V2.0

95nracer · 04-21-06, 01:02 AM

I've tried setting my ecu to run 4x720's, but when I do it runs way lean and dies. If I richen it all the way on the palm and turn the FPR up some it will idle but barely. So I ended up setting it to 550's + 720's and I've tuned around it.

I'm running 4x720 injectors that have been flowed tested and they actually flow 850cc's.

What would cause this problem? Is the ecu just taking to much fuel out? I have the right resistors in and the fuel pump is hard wired to the battery with a relay.

I love the ECU so far! I just have to do more reading on timing control and adjustments.

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turbo2ltr · 04-21-06, 10:34 PM

This does not sound right. How do you know its lean? Are you using a wideband?

720s that flow 850? Sounds kinda odd.

95nracer · 04-22-06, 12:01 AM

Yes I am using a PLX M-300 unit. I've been using this wideband for about 2 years now and it has been spot on.

At first when inputed for 4x720cc injectors and started the car it would die right away. So I first thought it was super rich. I turned down the FPR to 37psi static pressure and turned the fuel lean on the palm. Started the car up and it died right away. I decided to try and turn the fuel all the way rich at idle (-4 @ lowest rpm setting) Started the car and it barely idled the AFR was high 13's to low 14's. Turned the static pressure to 43 and the AFR's where still in the 13's and it idled very rough.

So I set the Palm to 550's and 720's and leaned it just a little at the lowest setting's. Started the car and it idled fine the AFR's where in the mid 12's.

I have a rewired walbro pump that is hard wired to the battery with a relay of the stock wireing harness without the stock switching relay that is next to the AFM. Aeromotive FPR with -6an lines.

Kieth at KGparts flowed the injectors for me. I've just recently had him flow some injectors for me and they all where 720's. The Venoms flowed 795 and the Greddy's flowed about 760 to 780. This was @3bar.

I've been using the 550 and 720 setting and the only problem I have right now is trying to tune out the overly richness that I have around 3000 to 4000 RPM's. I'm still able to match my own times in the quarter though when I had the Rtek 1.5 atleast, but my traps have gone up from 109 to 111. So hopefully I can tune this car out a little better and maybe raise my traps to around 115-117 where I want to be.

Henrik · 04-23-06, 07:44 PM

Your sure that you have 720's in the primaries? How rich running are you
seeing in the range before the secondaries come on?

-Henrik

95nracer · 04-23-06, 09:42 PM

Yes I'm running 720's all around.

On the logs it says 10.05, but on the wideband it blips from 10.05 to the display reading rich. This is in the low RPM's 3-4 thousand, but in the higher rpm's it stays around mid to low 11.

I just did some further adjustments, but I haven't driven the car yet to get some logs in. Maybe tomorow.

Henrik · 04-25-06, 02:03 AM

OK, I'll check out a couple of things here. 10.0 would support that you
have 720's as primaries. btw the 10.0 blipping to rich is due to the
wideband sensor itself, 10.0 or so is about the edge of the range
that the sensors work for gasoline.

-Henrik

95nracer · 04-25-06, 07:44 AM

I also have the secondaries coming online like stock near 3800rpm. Maybe this will help. Around 3850rpm the AFR's blip to 12.2 at the hightest then smooths out to around high 10's the rest of the rpm range. Highest boost logged is 9 psi.

This is pull was done on Apr 20 and its a 3rd to 4th gear pull.