Re: Fuel injection? Open or Closed loop?
 

Just my opinion, but unless you have marginal traction, the tune that makes the engine run at it's peak performance will be the most consistent.

I suggest that you clean up the drivability area of your fuel table, then either put it in Open Loop, or set the closed loop to turn on about 300 rpms above your converter flash RPM.

Re: Fuel injection? Open or Closed loop?
 

I have never spun yet but I will be running on a normally not so well prepped track this Friday night. If it'll hook at this track I should be good.

It sounds like OL will offer most consistency. Do you agree? Thanks again!

Re: Fuel injection? Open or Closed loop?
 

Since those tracks pretty much have their own row in my fuel table, I run the same tune all the time. I use the FAST logger, play it back while I have the tune I'm running fuel table open, click higher RPM, it highlights the cell it is using. I only tweak that cell. The others are corrected at tracks where the Baro The top 4 rows in my VE table are: 102,98,96,90 KPA. Everywhere I have been uses one of those four rows at WOT. My vertical columns (RPM) are in 500 RPM increments. I never have to screw with my FAST XFI ECU anymore.
I would work on my idle and part throttle. I like my plugs clean.

Re: Fuel injection? Open or Closed loop?
 

Thanks again Ed and to all of you. I really do appreciate all the help!

Re: Fuel injection? Open or Closed loop?
 

Darrel, you can set the minimum RPM for Closed Loop high enough to only function at WOT until you get your idle and part throttle. If your O2 sensor in in the collector, closed loop can make your car very rich. Big cams with a lot of overlap will pull clean air in the collector, tricking your ECU into "thinking" it is running extremely lean, it will really pour the fuel to it to correct that perceived lean condition.
The 2 step has a similar effect. Misfires from the rev limiter put oxygen in the exhaust, which looks lean to the wideband & ECU as well.
Mine shows over 15-1 sitting on the starting line, on the 2 step. If in Closed Loop there, it gets so rich it won't leave. My converter flashed to 6200, air/fuel doesn't clean up until 6500/6600. I think it would be making false corrections below that. So, I can't enable Closed Loop until 7000. My VE table has 500 RPM breakpoints. I have worked on my fueling until it never makes over a one percent correction in Closed Loop now.
Might see what David says about this, but it has worked for me.

Re: Fuel injection? Open or Closed loop?
 

Forgot to add: David (pretty sure it was David, I'm old) told me I should put my O2 sensor in a primary tube, for corrections from Idle & up.
I have since had mine on Patterson's dyno, with eight O2 sensors. I run mine in sequential mode, so I can correct each cylinder. Now, the sensor in one primary on each side should be fine. I had nearly a 5% spread between cylinders before. They are all very close to identical now.

After having run at all the tracks in our area, I log the first pass at each track now, never have had to touch it the last couple of years. Much simpler than running a carb.

Re: Fuel injection? Open or Closed loop?
 

The Holley system will not allow closed loop on the 2 step. Closed loop happens at about 4500 rpm off the two step. My Camaro qualified better than usual in Denver but my Firebird wouldn't run the index today in Super Stock. Not sure if it's broke or I just don't have the tune right. I leaned it to 13.1 from 12.7 after 6000 rpm (per suggestion from Duane Dickens) for last qualifier in the morning so we'll see. Thanks again!

Re: Fuel injection? Open or Closed loop?
 

13-1 is not lean at all "up there" at Denver. I would try 13.5-1. I'm surprised it likes 12.7-1 best at sea level. But, wide bands don't always give the same numbers. Be nice if they did. I bought a stand alone wide band set up so I could log both banks. Bought from the same people as the first. My original deal showed 12.9-1, the new one 12.5-1. Put it on Patterson's dyno with a wide band in each primary tube. Not that far off. Moved my original wide band to the other collector on the dyno. Both sides the same. In the car, one side still showed richer. Swapped sides with the original ECU wideband & the add-on, rich side moved too.

Re: Fuel injection? Open or Closed loop?
 

I ran .03 under the index far enough yesterday morning in the last qualifying round after advancing the timing two degrees and leaning it out per Duane's suggestion. Why does does high altitude like a leaner AFR? I may try leaning it out more at this weekends race but it's tough to tell anything when you only get two time trials before eliminations. Thanks again Ed. I ain't giving up yet!

Re: Fuel injection? Open or Closed loop?
 

Less oxygen in the air.

Re: Fuel injection? Open or Closed loop?
 

Not sure I was clear, I have my spark & fuel tables (SD mode) set up in 3 Kpa increments in the range 90 Kpa & up area. Depending on Baro, different elevation tracks run off a different row in those tables. No Problem, and usually Houston run off the same row. Noble, OK and Topeka, KS a row, Tulsa & Ennis a row, etc. Always log it, seldom havebto touch it.
Well, my two sets of heads have their own fueling tables. My Hetler heads need close to 5% more fuel at higher RPM.

For idle, and driving in the pits & return road, I had a 24" collector extension made at a friend's muffler shop. Has a 45 degree Bend st 12". Put my FAST XFI into Closed Loop& Learn Mode. Drove it up & down return road, and idle, while tapping the L key in each VE table cell.

Runs clean, with white spark plugs now, in Open Loop. Doesn't smell up the shop. I set the target A/F table to 14.0-1. Have not had to touch that for over four years now.

Re: Fuel injection? Open or Closed loop?
 

Thanks Ed. I'm still at it and making small improvements. I picked my Camaro up .13 at the Denver divisional test and tune by taking more fuel out of it. Next race was Denver national and I lost a tenth. Next race at home was a tenth slow. Then the trans started pumping large amounts of fluid out of the pump. Bushing was out. Discovered a forward clutch fiber plate was broken and three plates burnt. Picked up .12 at race last weekend after fixing trans. I'm at 13.2 AFR at WOT now. Going to try 13.0 at 6500 rpm and up next weekend. I'm a little concerned about the forward clutch in trans (200). The clutches I ordered were thicker than what I had. It had 5 fibers in it before and had to take one out to get the new clutches in. Anyone else having any luck with 4 clutches in the forward clutch pack or should I get the thinner plates and tear it down again?

Re: Fuel injection? Open or Closed loop?
 

DG, Answer is..it depends.
Yes, you could make it hold with 4 frictions, but you probably wouldn't want that much line pressure, seeing it's a bit of a power loss.
All depends on how the direct is set up.. How much pressure? How are you full feeding it? What kind of low drag items?
If you're tearing up direct stuff, you'll need to figure out why. It's a fairly weak area in a 200.
Tim Wudarzcyk is near you, or not too far anyway?

Re: Fuel injection? Open or Closed loop?
 

Trans is still holding up well after a year now. Sorry I can't answer any of your questions. The direct clutch was good. Just a problem with the forward clutches. I need to at least pull the pan and inspect for debris.

Tim grew up in the city I live in now. He's a couple hundred miles from me. Always enjoy our conversations.

Thanks for the reply!

Re: Fuel injection? Open or Closed loop?
 

Oh. My mistake. My mind must have read it as direct, because that is where the trouble usually is. Never had that problem. Always had the writing on the frictions after a season.
Sorry...No idea.

Re: Fuel injection? Open or Closed loop?
 

If you do it in Speed Density mode, and only alter the V.E. Table cells the logger shows it to be using, next time you go to Denver you should not have to touch it. It will use a different part of the V.E. table at Denver than "down here".

Re: Fuel injection? Open or Closed loop?
 

I rarely mess with it now. I have my correction limits set at 3%. Very seldom does the data log show 3%. 1 or 2% most of the time. I normally only look at the data log at the end of a race but I don't always do that. It just works. Thanks for all your help.

Re: Fuel injection? Open or Closed loop?
 

Your Stocker must wind up slow enough the corrections hit the right cells. Mine winds up too fast for that, other than high gear. Lean at 7000? Added fuel shows up at 7500, which likely did not need it. Have to keep mine in Open Loop. A faster ECM might help there.
Now that I have worked with it, at all the tracks, and weather, it’s always good when I log it. I use the IAT sensor as well. Mounted IN the intake manifold plenum.

Re: Fuel injection? Open or Closed loop?
 

Want to learn more? We are going to the source on Tuesday NOON EST. Watch here or on Facebook Live and have your questions ready!

https://youtu.be/Q5NdN9CS5rw