gen7 tuning gurus please step inside...

[ski_dwn_it]

Guys.

I got a gen7 system for my car. The car runs good for the most part - I am very rehersed in tuning stock ECMs - so that experience has helped. Idle and light part throttle is all within 5%, and plan on going back to fine tune further, but the car runs very well. I also touched up the AE for light throttle tip in.

I bought the innovative WB setup. Programmed analog output for 0v=> 10.0AFR and 5v=>19.99AFR

I did some very small bursts of WOT, but the car is tough to keep stuck to the road and did not want to blast down the area of road I was at until I knew things were not too out of line.

My question now that you have a little background is what is the method you guys use for fuel analysis. I took the one short burst WOT run and overlaid it over the VE table, and page up/pg dwn through the logs - but did not know and can not find exactly what I am suppose to be looking at.

Do you look at the AFR and correct to that? or do you look at the 02 fdback? I can't figure out if the 02 feedback's "units" is it %, volts, or what VE was changed to to obtain the desired commanded AFR?

This is about the only part of this I am stumped with....and unfortunately last night I got back late from business and did not get a change to play around with it more. I am hoping someone with some more experience can help me sort through this part....I am sure its quite easy and would really appreciate the help.

Got a race this weekend I would like to attend and a possible T&T I can go to to get the car dialed in tommorrow night. But hate to go there and not know what it is I am looking at and waste a bunch of time figuring this out.

Also any other good sites (found quite a bit here) that would be helpful would be great.

Thanks a million....:cheers:

 

[norbs]

The feedback is a decimal number or multiplier co-efficient. if it says .85 it is removing 15% fuel 1.10 it would be adding 10% fuel. You must look at the a/f and o2 correction during wot operation, preferable in 3rd gear, not after a shift, not de-acceleration or acceleratiing. Log the rpm, boost, a/f,o2 correction, maybe knock and pw or duty cycle.

Overlay your log to your ve map and remeber the data point numbers that you got smooth data (ie 3rd gear pull) Correct a few percent only at a time . Do another pass over wise you can overcorrect as there is some lag to the o2 correction and will slighty throw you off. What is your a/f fuel ratio at wot?

 

[ski_dwn_it]

Thanks norb for the clarification....

What I find cumbersome with the system is scaling the axis...I have it unconnected from the ECM and took it into the house to play with it - perhaps that is why the scaled map axis selection is not working.

What I would like to do is shuffle the RPMs around, but it seems cumbersome that the VE values stay independant of the RPM in their respective cells - so I have to manually move them around????

going to head out this morning and connect to the ECM and see if then the scaled MAP axis enabled makes this easier to do. Any advice would be helpful.

Also same as above it might be cause I am not connected to the ECM, but I would like to enable the power enrichment mode - for added resolution in part throttle and more RPM for my WOT AFRs. But the threshold and Target AFR is unaccessable.???? Again might be cause its not connected to the ECM

any enlightenment would be appreciated on how to active this/these functions.

Thanks a million!

 

[norbs]

While your offline do you have the key plugged into the laptop?

 

[ski_dwn_it]

OK, got the key plugged in and had to also press f10 to get it to become operational....did not think of that since the ECM was not hooked up...but its now accessible...

Now that I have access to it...perhaps you can tell me if its possible to:

Have my part throttle up to 5000 RPM in the "normal" VE map table, and all my WOT in the PE table from say 5000RPM up.

My thoughts were I could get more resolution for my part thottle then put all the WOT on the PE table....but now that I have access to the PE table target AFR, I see it has the same RPM vs MAP as the original Ve table...so how would one trim the fuel if one chose to do what I explain above...or is there another way to accomplish what I need to do....

Or should I just create a racing VE and a driving table? Maybe that is the right thing to do.

Thanks for bearing with me, but stock ECM did not create these "good" problems I am now struggling with. lol.

Thanks for the help and thuoghts on what would be the best way to dial in my setup.

Going to try to hit the track tomorrow if the weather co-operates...

 

[norbs]

You can't do what your trying to do with the scaled axis on the PE map. You only can change the a/f ratio, but not alter the orginal ve table to suite your needs. Just set you threshold limits to abou 50% tps and maybe 3500 rpm. You should be running at least 11.5 a/f over 20 psi boost for safety. ALso i suggest you run the lm-1 sensor speed at 1/12 output, as its still too fast for the dfi to read i find. For pump gas you want to stay under 20 degree timing @20 psi boost. Cruise timing 45 will be ok and idle around 30-35.. I would use one program for now and just see how it goes. I would go to the negative o2 correction table and make sure it can't take out more than 10% fuel over 50% on that chart for safety. Good luck at the track and log each run.


P.s if you want to get sneaky you can hook up a switch and use the aux launch mode to make a timing map for race fuel or pump gas, using the timing trim setting chart.

 

[ski_dwn_it]

Norb...more thanks to you.

That was some very helpful information.

I am running a n/a motor right now...434ci that is in a vette, runs about 10.3s@131+mph.

The stock computer served me pretty well till I got this new cam then it went haywire. Hence the DFI.

I set my innovative up to 1/12th, I observed that it seems to almost change too quick and thought it might be causing some grief-so your information really helped me out there and may have saved me a few weeks or months worth of tinckering to only realize it later.

On the setup of a innovative, what is the best way to connect and perhaps I can tell you what I did and you can tell me right or wrong and were I may have gone wrong.

When I hooked it up, I simply spliced in the HEGO wiring and put:

Analog 1 (red wires on innovative) to the pink and blue (dfi)

and

Bare ground wire (innovative) to the black on the dfi.

I was concerned about the gounding causing a possible misread....can you shed some light on if this is right or not?

Again I appreciate the help...the car is ready to roll for tomorrow and want to see if I can click off some better ETs with this new system.

 

[norbs]

well the analog #2 is supposed to be for the 0-5v signal, but if you programmed the #1 the same way it should be fine. Well it you N/A then most engines make peak power between 12.7-9 a/f, but i would run it at 12.5 for now. As long as your dfi shows the same a/f as the innovate it will be ok. However i would ground the innovate power wiring right at the battery, to get a good signal.

 

[ski_dwn_it]

Norb,

Thanks for the input. I have output 1&2 setup exactly the same.

Ran the car today and am real pleased. Just got your last post, but I ran a target AFR of 12.8:1. It was rich to start off with ~15% Correction - ran 10.7s

After a few runs, and I had to reconfigure my RPMs to match the range I run in, which is much different than the street, so I was sorta left with creating a seperate tune for the track. My stall converter is 5000 RPMs to get enough resolution on the street and enough at the strip from 5000 to 7200, I needed to use two seperate tables.

With each pass I came back and would overlay the information and see how much correction was made. Each time back out I gained a little more, keeping everything else equal. Broke a 10.6 => then into the low 10.5s - for the air and little bit of tuning I did I am pleased with the Gen7 results.

I got it down to around 5% or less imost in the 2-3% range for all the WOT cells.

One thing I did notice was I am only getting up to 95.XX kpa....this threw up the flag that I might have a intake restriction. No?

I was expecting that my WOT would in the 101kpa range....that is were they were in the stock ECM. ????


Its really a slick package and I like the fact it does what I tell it. All too often with the stock system you got unsuspecting results - which was what truely bothered me with bracket racing. It would run dead consistant all day long, then out of the blue loose .2sec or gain .1sec. usually about 1 round from the finals

This system seems to do exactly what you tell it and my times were VERY consistant and predictable. While not the best ETs, the weather was not that great and suspent my ETs would have been in the 10.7range with the stock system.

Right now I have the HEGO connector wires pink/blu & black cut just above the connector to the HEGO. There I have both feeds that go to the ECM tied to the Analog 1 of the Innovative as described above. Should I remove the ground from the HEGO connector or just run another wire off that slice point, leaving them as is, and run that wire to the negative battery term?

I hate wiring ......always boggles my mind.

 

[norbs]

Leave the grounds to the o2 the same. Just connect the lm-1 ground to the battery to get a clean signal. I thought this ran 10.3 with the stock ecm though?

You would have to switch back and forth, between dfi and stock ecm to see what if gained/lost i guess. What was the atmospheric pressure at the track, it might have been low that day? But if your pulling a vacuum, it doess seem a restriction somewhere

 

[aDFIguy]

One (or more) of the logging variables should be barometric pressure. You can check that against your WOT MAP reading to see if you have any kind of restriction or not (sounds like you do).

You mentioned wanting to switch back and forth between different A/F maps... you can do this via the Nitrous controller even if you aren't spraying. Just set up the RPM/TPS/MAP thresholds on the Nitrous screen(s), enable the Dual Mapping A/F table, and set your timing trim as needed. Make sure you set the number of nitrous orifices to zero. This will prevent the ECM from adding extra fuel, but will allow it to switch between A/F tables and add/subtract timing on demand.

 

[norbs]

The NOS inputs switch to ground? or Positive?

 

[ski_dwn_it]

Thanks for the input guys.....

Here is one of my logs after a few attempts at trying to get this thing dialed in. This run produced a 10.52 ET, which isn't the best - but the DA was ~1800ft.

Let me know if anything jumps out at you. I know I was shocked to see that my shift point of 6800 was actually ~7500! Eeek...need to lower that to about 6300 and that alone will gain me some ET for sure.

One thing that is strange is my ETs were on target with a buddy that runs REAL well with the same setup - but my MPH was about 3-4 MPH off his. 60' times were about the same and he pulled through each interval a little quicker, but the MPH has me stumped.

We usually run about the same MPHs

This track is about .2sec slow also from what they told me - so I am pleased with the first time out with the new system. With some more tweaks it should come around. Thanks for the prep work - it made it much easier.

You input is appreciated.

 

[aDFIguy]

Nothing serious really jumps out in the log -- except your MAP reading. Not bad for the first time out.

Norbs, use the ignition voltage feed provided in Pin E of the Nitrous connector to enable Pin C for Stage 1, Pin D for Stage 2, or both C&D for Stage 3 Nitrous.

 

[ski_dwn_it]

Yeah I saw that too, but with the key off the MAP is around 91/92 meaning that the BP was not real high that day, and I am dropping about 3-4kpa - which I think it about 1 or so " of vacuum, I think I have seen that before....

What do you guys think?

My buddy that I ran with during these runs went back to PRP, where we usually run at, and he ran a 10.3@132, and I was only a few hundredths off this the day the logs were made. I am going to lean it out a little on the top end and hopefully gain some ET.

At the end of the day we compared plugs and mine were richer looking than his, and the car gained some in the last two runs with the addition of spark, so I think a little leaner mixture might be the ticker. Not to mention from these logs, I am WAY overshifting. WEll I should say by the time I react, and the shifts take place its too high in the RPM band.

Keep the suggestions coming...this is a good learning experience and I have not seen many posts about tuning the GEn7 system.

What do you guys think the AE looks like. The car 60' ed better than its done in the last year or so. 1.46, spinning so its making more power in the bottom end than ever before.

 

[norbs]

I think the lm-1 is a bit fat in its readings so you may have to lean it back a bit. keep checkning the plugs. I have heard the lm-1 being off up to .5 compared to the accel "brick" but have not tested it yet in person.

 

[aDFIguy]

You haven't mentioned much about your combo, so I don't know if this will do anything or not, but... If you have an IAC on the engine, program your throttle follower table to slam it open above 50% TPS (or whatever value you want) to see if you can get a little more air into the thing at WOT. See if your MAP reading changes at all.

 

[ski_dwn_it]

Guys here is some information about my setup.

434 C.I. Dart Little M Block, M2 T1 Brodix 227cc Heads, Custom Fabricated "Jeb" Single Plane Intake, JE Forged Pistons, Crower Billet 6.0" Rods, 4340 Forged 4.0" Crank, Milodon Pan, Lunati Cam 264/272@.050 .650 Lift Solid Roller.

The car runs pretty good, with a best of 10.33@133MPH at 3400lbs and through full exhaust with Muffs.

 

[norbs]

Nice set up, and will be testing the "brick" vs the lm-1. Stay tuned!

 

[blownvette]

Originally posted by ski_dwn_it
Guys here is some information about my setup.

434 C.I. Dart Little M Block, M2 T1 Brodix 227cc Heads, Custom Fabricated "Jeb" Single Plane Intake, JE Forged Pistons, Crower Billet 6.0" Rods, 4340 Forged 4.0" Crank, Milodon Pan, Lunati Cam 264/272@.050 .650 Lift Solid Roller.

The car runs pretty good, with a best of 10.33@133MPH at 3400lbs and through full exhaust with Muffs.

http://forums.corvetteforum.com/showthread.php?t=1053447&page=3&pp=20