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Old 05-01-2010, 10:31 PM   #1
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Default Switching to VE

I am about to FINALLY get the 99 (turbo) with the Adaptronic running again. I finally forced myself to quit working on the LS1 car; I got the motor back in the turbo car today.

I have not touched the ECU in awhile and there have been several updates with WARI and firmware, including the switch over to VE. So, if I install the new WARI, flash the new firmware, and reload one of my older PW based maps, am I going to cause kitten cancer or will all be OK? Does the Adaptronic (or WARI) take care of the VE conversion? I want to use the latest map I had that the car ran well on.

I looked around in some of the other threads and did not see anything specific. Sorry if I missed it.
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Old 05-02-2010, 12:49 AM   #2
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One of the drop down menus in Wari at the top of the screen says "Convert inj ms to VE" or something like that. I haven't tried it yet, but I really don't care. I've gotten used to the inj on time unit and somewhat prefer it now. Everyone else deals with injector on time so I figured I might as well convert myself instead of my tables.

Just like forcing myself to think in Celsius instead of fahrenheit. Just had to make myself do it.
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Old 05-02-2010, 10:11 AM   #3
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the VE conversion is not exact since the VE of your engine is unknown. plopping in the engine size and injector flow (at your rail pressure of ~60 psi) will get the map close, but not perfect.

it will likely need the idle fuel area retuned and the rest can just sort itself out on rapid learn.
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Old 05-02-2010, 11:01 AM   #4
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Good info, thanks.

Chad I will have to make the same call on deciding which way to go long-term. I was also getting used to using DC instead of VE. I RTFM-ed last night a bit and read the discussion on how VE can make initial setup easier, but that is not applicable in my case. There is some implication on the adaptronic site and on the boards that VE provides better accuracy.

One thing though, and this is speculation, if VE is requiring more CPU time due to the calculations, where did the computation overhead come from? Why I ask is I remember the developers writing on one of the adaptronic board threads (a feature request discussion) about how they were already pushing the limits of the processor as it was. That was before adding VE. I am going to be adding a PWM driven output (HSV for WI) that will also require calculation. If I stack both of those on, VE and the PWM out...

Yates how are you liking VE mode on the Adaptronic? Anything you like about it over DC mode?

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Old 05-02-2010, 12:06 PM   #5
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the thing about VE that makes it nice is that you dont have to do as much math when you want to add or subtract a fixed percent of fuel because VE *is* a percent of fuel (in theory, the "trim" value should be in the same units). it also "flattens" out your map so that you do not lose resolution as MAP decreases. example: with pulsewidth, my minimum adjustment increment is .002ish* for a 1.500 fuel value. that's .13%. at 300 kPa, it would be .002/17.000 or .01%. I certainly don't need 10x the resolution at higher loads. With VE, it's always the same at any MAP value. which is I think about .02%* which helps tuning lower loads a bunch.

* adaptronic doesn't use round numbers, but it does display the actual numbers. if you type in .60, it may show up as .59 because that's the nearest rounded number it can use. same for VE. I'm estimating the smallest increment.

the bad thing about VE is that your logs now have this meaningless Inj (ms) value in them that doesn't correspond to your fuel map. You can SORT OF get around this by postprocessing your log and creating your own VE equation to convert MAP, RPM, AFR into a calculated VE. I've done this and I'm not sure how great it is yet. If Adap was smart, they'd let you log VE directly. Ultimately I don't rely on ms of injection anyway... so it's not a huge issue.
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Old 05-02-2010, 12:43 PM   #6
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ZX, you know, if you need any help on that ls1 im game.
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Old 05-02-2010, 06:17 PM   #7
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Quote:
Originally Posted by y8s View Post
the VE conversion is not exact since the VE of your engine is unknown. plopping in the engine size and injector flow (at your rail pressure of ~60 psi) will get the map close, but not perfect.

it will likely need the idle fuel area retuned and the rest can just sort itself out on rapid learn.
Is 60psi with a different pump or regulator? I thought we had 3bar fuel pressure? oh boy....
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Old 05-02-2010, 07:02 PM   #8
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Quote:
Originally Posted by dgmorr View Post
Is 60psi with a different pump or regulator? I thought we had 3bar fuel pressure? oh boy....

NBs are returnless and maintain 60-65 psi at all times.

Though the NBs are known to lose fuel pressure at higher RPMs so a Walbro 255 is a recommended upgrade to maintain the required fuel pressure.
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Old 05-02-2010, 07:38 PM   #9
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Y8S good point on the resolution. I had not considered that. Having to calculate VE in MLV I suppose is not a big deal.And I suppose VE is a somewhat arbitrary number anyway in a tuning sense. That is, I do not look at a particular RPM point in the log and think hmm, the VE is a little low there. I am usually looking at other things like MAP, AFR, IAT, %DC, etc.

Chad is right about the fuel pressure and the pump. In fact I have a Walbro 255HP in my tank.

Quote:
Originally Posted by chicksdigmiatas View Post
ZX, you know, if you need any help on that ls1 im game.
Thanks but the Adaptronic is on the turbo car. The LS1 car is using the GM ECU. I have grown weary of seeing this expensive, built BP engine sitting in my garage, and the 99 sitting in the driveway, as I drive my comparatively weak handling gas hog truck to work. So, though there is still a to-do list for the LS1 car, I have forced myself to quit working on it until I get the turbo car running

No worries though, there is still plenty to do on the LS1 car, including modifications to the rear diff mount.
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