JV, why don't you raise the idle to 850 thru the computer. If the IAC count is too high you can increase the air bleed holes in the throttle plate and keep the plates closed and TPS at 0% open. 750 sounds low and risks reversion.

This is where we'll all be able to start helping each other out!
There is two ways you can fix that theoretically. One is the IAC speed and other is the timing trim. You can speedup or slow down the IAC reaction time which will regulate how fast or slow it will deliver additional air (and fuel) to compensate and stay at the target idle speed. Timing trim will allow you to make the timing advance 10 degrees or whatever you specify as soon as it sees a drop in the target idle speed. One of these will certainly cure you problem. That's the beauty of these things;)
I only have IAC capabilty with my current ECM and I had to fight it a bit with the big props also. Just going on meomory, I think I set the idle manually (with the screw) a bit above my target idle speed. This helped by not making the IAC work too hard. There's a happy medium there.
However, with our new FAST ECMs with timing trim and IAC speed control, this should be an easy fix.
Later,
Dave

haltech efi
 

HPJunkie


I use the E-6A on my 540ci. tunnell ram motor, it works great. It did take some time to figure out the air idle motor. It idles at 750rpm and is a pooch docking.

Hi Jim V! Goin to the Ozarks this year? Hope so I saw you in the last years magazine. Did Tom Earhart Help you set it up? I did dyno my motor at his shop, at your recomendation and all is well. Thank you very much! Do you tune the computer yourself now? Did you set it up on the dyno and then on the boat? Should I do it with a procharger? Greg

Greg

Yes, I will be at the shoot out. Tom has been, and still is, a great help. He set it up and educated me so I could tune it myself. I did not dyno the tunnel ram motor, I tuned it in the boat with egt and 02/air fuel guage. Im sure it will work great with the pro charger but I would set it up on the dyno first.

I am looking/planing to go the fast system. I talked to NordicHeat last week & he has put the bug in my head. How are everyone elses systems working? Would you do anything different now.

Plan to use the sequential system with wide band O2 sensor.

Turbo did you get your fast unit yet? Greg

Not yet. been draging my feet. Been having to do real work instead of working on boat this summer. I did not want a problem from keeping me from getting to the water almost everyweekend. Hope to get started in next month. I am now planing on going the bank to bank since it looks like that is what everyone is recommending. Also planning holley manifold that already has the buds in it, & 2000 cfm throttle body.

How is everone else systems working?

Flawless,
even been running closed loop all summer:D :D :D :D

Nordic are you convinced that the tuning on the system is over? I'm afraid that I'd keep fooling with it looking for more. I guess the question is there really an easy way to tell when you reach the end or optimum settings? greg