I asked a question on here a few days ago about the curent of the 1600cc Precision injectors. That issue is now fixed, however, Im having some trouble getting this car to idle. A/F is about 13 to 1 at idle but is surging real bad, from about 800 to 2500. Are there any other parameters in the MoTec software that need to be change for the bigger injector, or is the entire map junk now???

I have adjusted idle air, messed with the IAC in the MoTec and just cant seem to get it to not surge???

any info is greatly appreciated. thanks

 

What pulsewidth is it idling at? Alot of times it'll idle alot better if you richen it up a bit with that size injector. When you get below 1ms it's kinda hard to idle the car. It's going to take some work. I went from 1000's to 1600's on the race car and it took me quite a while to get it all ironed out. The 1600's are really big injectors! Also, what's your base fp?

 

base fuel pressure is 40psi, and I believe the pulse width is 2ms. I'll go check that though.

 

I doubt it. I'm around .9ms on mine.

 

I checked and it was at 2ms. You are talking about the FPW (ms) right???

Do I need to change this?? And if so, where about in the program?? Thanks

 

There should be FAPW and FEPW in the logs. One is actual pulsewidth and one is effective pulswidth. You can idle the car while the computer is hooked up and just watch inj. pw in the view screen. If you want to send me a copy of your file, i'll look over it for you. tony2904@msn.com

 

1600's don't like to idle under 1ms. I agree with tony this is where your problem is. 1600's are also not the easiest to map for part throttle but will work it's just going to take some time.

 

cool, when I get home I will email you the file.

thanks

 

you should be able to get them to idle it is definately possible. mine idle at 1000 rpm @ 14.7 afr.

i dont use the iacv, i just have the idle holding 1000 rpm on the set screw on the throttle body.

my technique is having all the cells in that range the same both for fuel and ign. you can also scale your maps resolution higher in the idle range that gives you some good control.

to get the drivability portion done, i had to do it on the dynapak... it was simply impossible to get the motor running smooth partial slow speed driving using street tuning, which im normally pretty good at.

don't give up though its definately doable.

 

also if you are sticking with the iacv you want to bump up your idle with the set screw so that your lowest idle point is the set screw. the iacv only activates on cold start, steering input to compensate for power steering load, and electrical load when the lights flip on ect, and ac.

 

How do you change injector pulse width. I cant find it anywhere in the software?

 

The numbers in the fuel map are what you change, to change the pw. The pulsewidth is how long the injector is open. The number in the fuel map is what tells the injector how long to stay open.

 

Big Injectors like that, you gotta ADD Fuel Value, compared to a smaller injector to get it to idle...Big Mistake alot of people make when switching to a large injector.

 

well there's a little secret i know that really gets those injectors to work well.
But i can't share that info... lol....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Enzo-Racing &raquo;</TD></TR><TR><TD CLASS="quote">well there's a little secret i know that really gets those injectors to work well.
But i can't share that info... lol....

</TD></TR></TABLE>
money

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Enzo-Racing &raquo;</TD></TR><TR><TD CLASS="quote">well there's a little secret i know that really gets those injectors to work well.
But i can't share that info... lol....

</TD></TR></TABLE>


Thanks

 

my secret was getting the tony1 crank trigger. it honestly made the biggest difference in the world without it the m800 on my car would be useless.

 

-UPDATE-

Well shes idleing like a champ now. Thanks Tony for informing me about the individual cylinder enrichment. That helped a ton, my only problem now is under a load down low. Basically when I take off from a stop, its really jumpy, the car bucks pretty bad until I get it above the idle area on the map that I worked on. I guess I'll mess with it somemore tomorrow. My stupid neighbors have already complained about there place smelling like gas...hahahaha. I dont know how many times I had the plugs out after fouling them........man!

 

Just keep working with it, part throttle is a bitch with those injectors!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">Just keep working with it, part throttle is a bitch with those injectors! </TD></TR></TABLE>


haha, wow... i thought it was pretty easy w/ the aem last time i did some 1600's... hahah

 

Yeah tuning with 1600's on a honda for the first time makes you think your working with a rotary.. hehe... Fouling plugs, stinking of fuel, raw gas pumping out the exhaust...

You'll find idle is easy and wot is easy it's getting the part throttle thats tricky.
Once you'll get it you'll notice WOT will feel NUTS.

 

This is on a Subaru, not Honda. But yeah, I have dealt with everything you stated....haha

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDogg &raquo;</TD></TR><TR><TD CLASS="quote">


haha, wow... i thought it was pretty easy w/ the aem last time i did some 1600's... hahah </TD></TR></TABLE>

probably cuz your using a dynapak.

dynapak tames those 1600cc without flinching.

 

Well 4 days later I have got it tuned in. Its holding a steady idle, partial throttle is exceptable, and WOT is awesome!!! This would have been expensive to learn on a dyno!!!! Now its time to tweak it in with some dyno tuning.

Thanks to all that gave input......I appreciate it. O yeah, I was also chasing my tail with a bad ground for #2/#4 coils, and a bad #4 coil. Once I figured that out, as well as the individual cylinder enrichment that Tony brought to my attention, it was just a matter of time and patience.

thanks again

 

i'd like to learn about some individual cylinder enrichment?