?s on low impedance box
I run one. I made it.
atleast on mine, it was a simple splice inline with the 8 injector wires from the PCM. A 12V supply to the box, and a ground. Then tune for the injectors.
There is a point where you can't get the pulse width small enough due to PCM limits, and you will have to run open loop at idle via the PE table. Or run open loop all the time. I use leaded fuel only, and removed the stock O2's in favor of an in car wideband. So it didn't bother me any
atleast on mine, it was a simple splice inline with the 8 injector wires from the PCM. A 12V supply to the box, and a ground. Then tune for the injectors.
There is a point where you can't get the pulse width small enough due to PCM limits, and you will have to run open loop at idle via the PE table. Or run open loop all the time. I use leaded fuel only, and removed the stock O2's in favor of an in car wideband. So it didn't bother me any
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From: Austin, TX
Originally Posted by y2khawk
There is a point where you can't get the pulse width small enough due to PCM limits, and you will have to run open loop at idle via the PE table. Or run open loop all the time. I use leaded fuel only, and removed the stock O2's in favor of an in car wideband. So it didn't bother me any
Anyone having good results with the bigger HighZs.
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Acceleronics We have installed several of Acceleronics inverters without any issues on C5's! Drivability is a dream. Our latest dyno was 701 rwhp w/75# injectors. We are still playing with the intercooler so we have not put it back on the dyno. With the stk inj offset and proper VE tuning this thing is a dream come true (as long as you have enough fuel pumps!) I will never run those slow *** 50#ers again! Check out the #'s! http://www.vettepieces.com/dyno/dyno_rich_02.html
Since this dyno we reworked the torque converter (2000 stall-oops to 3900!) and pulled a 10.79 smokin the drag radials for half the track! Then we drove it home! No trailers here! We have dyno emissions tests to boot!
We are currently building the suspension with bearings instead of bushings and have fabricated aluminum disks to replace the rubber in the torque tube.
Real wrinkle walls this season!
Since this dyno we reworked the torque converter (2000 stall-oops to 3900!) and pulled a 10.79 smokin the drag radials for half the track! Then we drove it home! No trailers here! We have dyno emissions tests to boot!
We are currently building the suspension with bearings instead of bushings and have fabricated aluminum disks to replace the rubber in the torque tube.
Real wrinkle walls this season!
Originally Posted by Thomas
With the stk inj offset and proper VE tuning this thing is a dream come true (as long as you have enough fuel pumps
-Geoff
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I'm looking to find out what size lowZ injectors you can run without having to fight to make it idle. Stock offsets and just injector flow tuning is what I'm hoping for (for non WOT tuning).
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having it idle is not really the issue. It's trying to run closed loop at idle, the PCM will clamp the pulse width at idle with anything much larger than a 70'ish injector. The fuel trims continue to try and shorten up the pulse, when you come off idle you're in a huge lean hole because of the fuel trims.
offsets and IFR are all you really need to mess with if you stay below a 72 or so injector.
offsets and IFR are all you really need to mess with if you stay below a 72 or so injector.
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Matt, now, when you say that happens, is that after you have gotten zero trims at idle?
I saw somewhere that ChrisB or LJ had posted success getting them to work with lean idle trims, what do you think about that?
I saw somewhere that ChrisB or LJ had posted success getting them to work with lean idle trims, what do you think about that?
where are the zero trims coming from?
the clamped pulse width is uneffected by anything the trims do, short or long. So the trims continue to learn down, until they can't go any more. So both long and shorts are full negative. As soon an you give it any throttle, and it needs more fuel than the clamped pulse width you have to drive through the full negative trims.
the are ways around it, PE at idle to turn off the trims or open loop. you can't mess w/ the IFR or the MAF curve cause the minimum clamp overrides everything it seems.
the clamped pulse width is uneffected by anything the trims do, short or long. So the trims continue to learn down, until they can't go any more. So both long and shorts are full negative. As soon an you give it any throttle, and it needs more fuel than the clamped pulse width you have to drive through the full negative trims.
the are ways around it, PE at idle to turn off the trims or open loop. you can't mess w/ the IFR or the MAF curve cause the minimum clamp overrides everything it seems.
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From: College Station, Tx
Originally Posted by y2khawk
[...]the are ways around it, PE at idle to turn off the trims or open loop. [...]
Yep, those are the only current options afaik. LJ mentioned adding the ability to have a constant negative offset to some of the new acceleronics boxes - say it was 1msec. A reported pulsewidth of 2msec would actually be 1msec, 18msec would be 17, etc. You could compensate for this by altering the maf curve, since on-time will be ~ to airflow - but as you got larger it would have a smaller effect.
On the other hand say the unit clamped at 1.5msec - this would give you the ability to run 0.5msec pulewidths.
it would take a bit of playing around to learn ho to properly compensate, but it is definitely do-able, and would *probably* fix that issue.
But much simple is to just run PE at idle.
Originally Posted by ChrisB
But much simple is to just run PE at idle.
Thanks for the info guys.
-Geoff
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From: Austin, TX
Originally Posted by White_Hawk
So what is the trick to setting this up in LS1edit? Do I change the "MAP to enable" to be above my MAP at idle or is it more complex than that? I don't see much else having to do with idle in the fuel tab.
Thanks for the info guys.
-Geoff
Thanks for the info guys.
-Geoff
Originally Posted by QuickSilver2002
My guess is that it is in the PE enablement tables (In the Fuel tab). There is one that is throttle% x RPM. I'm guessing you just set the low RPMs to go into PE with 0% TP and then you jump back out of PE once the RPMs go past 1000.
OK, I see that, then do I set my PE vs RPM table to 1.0 at the same RPM's?
-Geoff
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Originally Posted by White_Hawk
Did you tune this without the MAF or did you have to play with the VE tables to get the idle right? It sounds like you have gotten pretty good at this. Thanks for the info.
-Geoff
-Geoff