I've been tuning this car for awhile now but from now on I am going to keep all the tuning info only on this thread as this is the better place for it to be.

Just added a AFPR for new people to my thread.

Heres the latest datalogg, just the WOT as it still needs more fuel taken out. I adjusted the F28 constant so it would idle normal again, then I recently adjusted the AE tables F21 and F22 but had not results. Still 10.xx Afr when first into WOT. I am now going to change the lower (91-130kpa) VE fueling and see if that helps.

For crusing im at a great 14.5-15.0 for most of the log, this is all in open loop as I've never put it into closed loop. Theres really no point as this is just to drive arround a little and then drive to the race track.

 

Thanks Rbob for the picture of the table. Theres a huge difference between mine and this one.




Heres my current one. The chart didn't want to copy but the values are in the same decent as the table above.
518.81
518.81
518.81
946.06
946.06
946.06
732.43
640.88
579.84
518.81
518.81
518.81
518.81
518.81
518.81
518.81
518.81

Is a lower value a longer pulse width(for larger injectors) ?

 

it's exactly as the table name implies: it's an adder. as in, this many uSecs (can convert to mSec like BPW by dividing by 1000) are added to the calculated desired BPW to account for injector opening time based on system voltage.

 

Just had to set the fuel # back to the 43psi without the reference, and put the normal tune back in it. Ran out of time for the night but hopefully I can figure it out because im getting minimal results when it comes to AE and hunting. But the funny thing(car runs like a champ when WOT under boost)

 

Would those values on the GN's offset Vs. Voltage table be the same for a MFPI? The reason I ask is because at this point I am thinking of starting over on the tune with those off sets and seeing if it helps. I can always go back to my other bins. But the main questions I have going though my head is that the GN is based on SFI injection and mine is MPFI. In too new at tuning to know what the difference is when it comes to fuel injectors, or if there even is a difference.

Thank you for any help or insite on the matter!

Im just thinking outloud as I can't go try it myself at the moment. But I do want to learn more info.

 

well.... the difference isn't so much MPFI vs SFI, it's that MOST MPFI fires twice per 4 stroke cycle, while SFI fires once per 4 stroke cycle.

and here's the potentially confusing part: shouldn't matter.

why? because all other things being equal, with injectors of the same size, to deliver the same amount of fuel, a double-fire system will show half the BPW that a single-fire will. both are delivering the same amount of fuel(offsets due to exact BPW and voltage not being accounted for).

now.... think about it. regardless of being in single or double fire, the table is added to BPW. and the table is used to define how much time is needed at various voltage to account for injector opening time.

same goes for the low BPW adder table. however, if i'm thinking about this correctly, it would probably be easier to determine if the tables are incorrect in double-fire than single fire, since whatever error is there will essentially be doubled in the double-fire situation.



you may want confirmation from someone who has experience with the algorithm of both though, can't say i've looked at the GN stuff in a long time or very closely.

 

I literly copied those offets that Rbob linked from the Grand National. I will admit, the car is much more responceive. This is mainly when at idle/in park and I open the throttle fast. Clearly a huge difference.

I obvously had to take some fuel out as it was stinking rich, I could hear the lope of the cam badly. So far I got the idle at 14.2-14.5 which is ok for th $59 mask. With no hunting or surging. The crusing Afr is close to what I had before, mainly in the 14.0-14.5 range. Keep in mind that this car is not intended for MPG although it is a V6 and still manages 20mpg+ in open loop, as long as I keep my foot off the peddle.

Before when I would go WOT on the car and then come to a stop it would surge badly, even before I added the AFPR. But no theres no hint of it. I also set the fuel pressure at 55psi at atmo. pressure.

I now need to re-tune the boosted area as it is lean at high ends of boost. Mainly 160kpa and higher. Those are close to 12.6-13.0. I only attempted those pressures once and saw those AFR's and immediatly let off as thats too high. I aim for 11.7-12 afr in my case under boost.

I don't have time today to tune and its misting outside. There no way to tune a boosted car in the rain, its basically worthless and only spins the tires once it flashes boost.

EDIT: Added some more fuel in boost, and removed more at idle. I attached a datalog. Boosted AFR's could use some smoothing but over all i'm about where I was at before the AFPR was added. And As I said before the throttle responce is so much better with the different offsets.

A little crusing data is at the top and the WOT pull is at the bottom of the datalog.

 

looks like boost is still building a little slow, did the new wastegate spring come in yet?

 

u need one of these http://www.ebay.com/itm/MSD-soft-tou...item231d125586

while its used as a revlimiter u can use it as a launchbox/antilag

 

Na its in PA right now, it will be here tommorow.