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The fuelling leaning out makes sense.
Fuelling is calculated based on milligrams per cylinder.
At 245 grams/sec and say 5000RPM it may be OK, this is 83 revs/sec.
At 245 grams/sec and say 6000RPM it is now 100 revs/sec.
As there is more revs/sec for the same air, there must be less air per rev in each cylinder, so the motor now needs less fuel.

Typically the max injector pulse width is at max torque, as this is where the motor is getting the most air per rev, as you goes past this power still increases as you are getting more bangs per second, but the bang is smaller than at peak torque.
A WOT plot of mgc Vs RPM gives the basic shape of the torque curve for a motor.

Hope this helps as hasn't confused you more.

yoda69

yoda69 wrote:The fuelling leaning out makes sense.
Fuelling is calculated based on milligrams per cylinder.
At 245 grams/sec and say 5000RPM it may be OK, this is 83 revs/sec.
At 245 grams/sec and say 6000RPM it is now 100 revs/sec.
As there is more revs/sec for the same air, there must be less air per rev in each cylinder, so the motor now needs less fuel.

Typically the max injector pulse width is at max torque, as this is where the motor is getting the most air per rev, as you goes past this power still increases as you are getting more bangs per second, but the bang is smaller than at peak torque.
A WOT plot of mgc Vs RPM gives the basic shape of the torque curve for a motor.

Hope this helps as hasn't confused you more.

yoda69

Thanks yoda, thats explains a few things. the 245 gs is where the lookup table is maxed at around 4800 rpm, so its not reading the increased air going in. Im just learning as i go here. Last night i experimented more with injector constants by cranking the values up a little more in the higher rpm/mgc regions.
Also adjusted base injector rate from stock upto 220ms/g. This made the car pretty rich. The short term fuel trims seem to be all over the shop. Bear in mind i know stuffing with this stuff is throwing my tune way out, but im sussing how different changes affect fueling, then i can go back to known good tune and make more edjucated adjustments.
Changing the base injector rate would clearly not be a good way of adjusting a/f as it affects the fueling across the board and throws the closed loop into a state of constant large trims, where as like andrew suggested using inj constants can be used to adjusted individual parts of the rpm/mgc fueling. Im understanding that the engine needs less fuel after its point of max efficiency/torque, but still unsure why it was leaning right out when i commanded more fuel through inj constants, as like you said the individual cylinders are needing less fuel due to less air past peak torque, but as a total volume of air is still increasing with engine speed.
I wanna try getting the open loop and pe a/f somewhere around where i want them, using the base inj rate and constants combined, then disable blm by use of high/low perameters and try and get the idle/closed loop areas of fueling somewhere back around +/- 2 or 3, just as an experiment. This is where i could really start to make use of an nvram i think.

Interesting point about changing the injector base rate. Wouldn't hurt to sit at stoic idle or whatever the commanded idle AFR is and make sure it is what it is with the WB. Do this at idle and then ad light throttle opening cruising with a bit of logging. Getting these areas right can really help the delco use its smarts and help you get an even nicer more economical tune happening.

krusty wrote:Interesting point about changing the injector base rate. Wouldn't hurt to sit at stoic idle or whatever the commanded idle AFR is and make sure it is what it is with the WB. Do this at idle and then ad light throttle opening cruising with a bit of logging. Getting these areas right can really help the delco use its smarts and help you get an even nicer more economical tune happening.

With the blm turned off do you mean ? Closed loop idle with the base rate cranked up abit its still keeping around stoich but the stft are working hard to keep it there.
Wow the wideband really tells the story the combination of raised base rate and inj constants was seeing some a/f ratios as low as 10.00 flat. W/b log is ace really can see the effects of changes in detail, should be able do get fuel sweet as now and then have a look at spark its all good.

Yeah, always a good idea to disable BLM when doing any tuning imo. WB is a great tool no doubt!

krusty wrote:Interesting point about changing the injector base rate. Wouldn't hurt to sit at stoic idle or whatever the commanded idle AFR is and make sure it is what it is with the WB. Do this at idle and then ad light throttle opening cruising with a bit of logging. Getting these areas right can really help the delco use its smarts and help you get an even nicer more economical tune happening.

all good for a standard motor
i've found with my new more "wild" cam in the 202 i am using alot more methanol than i was before, and you can definately notice it in the eyes and throat burn i tried to get it to idle with less fuel and she just wont have a bar of it

after the few small issues ive been having where solved, i finally got my first decent wot up to 180 ish logged with no errors and w/b logging.
got home to pick it apart, and its good and bad i spose.
firstly good, at wot throttle i was able to get 16d into the midrange and 14 up top with no knock retard, engine at full op temp, on a hard run through 3 gears which tells me my w2a cooler is obviously working well. also a/f according to wb is safe on the fuel settings that came on the tune
bad is after i backed off from the run to a cruise i got some mean k/r which i was having dramas with before if i even touched the gas pedal for about 5 minutes.
ive pulled some timing from those areas already and its in closed loop when this happens. ive put it down too extreme blower temps and stoich a/f dont mix well at any mg/cylinder.
also bad and worse is my car really is slow. going by my log it took over 6 seconds to reach 100kmh from a rolling start at 20ks. on top of that it took over 12 seconds to go from 100 to 170. so with the combination i have i should (typically) be looking at around 12.9-13.2 second quarter mile time at about 103-104 mph correct me if im wrong. if im taking 12 seconds to goto 170 from 100 then what hope have to even go from 0 to 150 khm in 15 seconds. i know these figures are far from exact but even with a -3 second error it still shocking. this dissapoints me ive suspected its a little slow for what it is but DAMM.
it has over 180 psi on every cylinder. its running as well at it ever has, has good fuel and fuel supply, and ambient temps where quite cool. the timing was from the good spark table no temp corrections etc.
not sure if ive posted my exact combo but here it is
vx sedan l67
79mm pulley sees 10 psi max revs
mace mini w2a intercooler plate
ported blower and lim
cam in214/ex222 lift 531/541 lsa 115 intense s2 blower. this cam was installed correctly using a degree wheel and dial and was exactly as cam card on a jp double roller chain and crow 105 springs manley retainers.
4 inch intake kn 9 inch pod. might have to get another dirty big v8 im in this hobby cause i like to be sideways and launch hard its not happening with this. ill take a vid of 0-110kmh and post the link see what you`s think.

my best is going 0-100 in 5.1 seconds with turbo buick on 7psi on 215's with an open wheeler i dont think an l67 would get that close without serious mods and then traction becomes an issue and slows you down as well.theres a list of the fastest l67's in aussie on streetcommodores most with the eaton still on do 13's max never see many in the 12's

delcowizzid wrote:my best is going 0-100 in 5.1 seconds with turbo buick on 7psi on 215's with an open wheeler i dont think an l67 would get that close without serious mods and then traction becomes an issue and slows you down as well.theres a list of the fastest l67's in aussie on streetcommodores most with the eaton still on do 13's max never see many in the 12's

here a small sample of some quick l67, theres bulk of them running 12s. but turbo might be the way to go for serious grunt. most guys with a 10psi pulley exhaust and rockers intake are busting out high 13s low 14s, add cam and cooler and tune and most go high 12s low 13s add diff gears and should be in 12s for sure on a healthy well tuned example.
i think i just over think shit too much blower was heat soaked surge tank seems to get real hot and inlet air temp up on a cold night goes heaps better . might get a g-tech meter to actually gauge the gains of mods. i hear there pretty accurate.
4 Name - xu6psi john
Car - vx xu6
Mods - XP Hot CAM, MACE intermidiate W2A intercooler, Ported Blower, Machined L.I.M, Machined/Shaved Blower Snout, MACE 68m Pulley, MACE enclosed pod (4" Intake), 81 degree thermostat, Yella terra fuel rails, double row timming chain, ls1 t/b, carbon ubend
Tyres - mt
Weight - ?not sure
Time - 12.32
MPH - 108.9
60ft - 1.76 (pb 1.66)

5 Name - Luciano (CJ_JET)
Car - VN Commodore L67
Mods - A2A cooler, 19 psi pulley, 5% balancer, Engine rebuild whit ARIAS forged pistons, chambers machined, double row chain, YT cam whit 1.7 ratio YT rockers, etc
extractors & twin 2.5" into 3" exhaust,Auto with 2,500 stally 3.73's gears LSD.gen 3 TB , custom tune
Tyres - MT Street Radials
Weight - 1350 kg (no driver)
Time - 12.358 (PB - 12.587)
MPH - 111 mph (PB - 109.9)

6 Name - Justin (ASTRO6)
Car - VP Wagon (astro6)
Mods - M90, FIT cooler, 2.6" pulley, VS cam, 440cc injectors, walbro pump, exhaust, LSD
Tyres - 26x15s
Weight - 1580kg
Time - 12.4 (boucning the rev limiter 1st to 2nd)
MPH - 110mph
60ft - 1.8

7 Name - Daniel Jenkins (Jenkos)
Car - VX calais
Mods - W2A intercooler (yt intermediate)
Comp cams XP hot cam 105lb valve springs, stock rockers, pacemakers 1.75, 61mm pulley, 3.73 mini spool, bunnings CAI, home ported blower/lim, gear box that wont shift properly lol
Tyres - mt radials
Weight - full less exhaust
Time - 12.5 (P.B. - 13.61)
MPH - 105 (P.B. - 104)
60ft - 1.6

8 Name - Jason (Orig3n)
Car - VT Calais
Mods - W2A intercooler
Y/T cam 64 pulley overdrive balancer
Weight - full
Tyres M/T street radials
Time - 12.5
MPH - 111
60ft - 1.80

9 Name - Luciano (CJ_JET)
Car - VN Commodore L67
Mods - A2A cooler, 19 psi pulley, 5% balancer, Engine rebuild whit ARIAS forged pistons, chambers machined, double row chain, YT cam whit 1.7 ratio YT rockers, etc
extractors & twin 2.5" into 3" exhaust,Auto with 2,500 stally 3.73's gears LSD.
Tyres - MT Street Radials
Weight - 1350 kg (no driver)
Time - 12.587 (PB - 13.20)
MPH - 177 km/h (PB - 108)

10 Name - Chris McCord (slowgtp)
Car - 1999 GTP
Mods - XPZ cam, ZZP IC, Stage 3 heads, TOG headers, 2.8 pulley, SFI balancer overdriven, ZZP race trans, Custom tune, Roll Master other stuff.
Tyres - Hoosier Quick Time Pros
Weight - 3750lbs
Time - 12.60
MPH - 108.58
60ft - 1.858

11 Name - Michael Gordon (SUPER SS)
Car - VT SS Commodore
Mods - FMIC (600x300*76), 17psi Pulley, XP-HOT Cam, Pacemaker 1 5/8" Extractors, Twin 2.5" Exhaust, Custom Tune, shift kit, 3.73:1 LSD
Tyres - MT ET Drag slicks
Weight - about 1700kg or so
Time - 12.611
MPH - 108.82
60ft - 1.884

12 Name - Daniel Lesic (Zeep)
Car - VTII Commodore S
Mods - Extractors + Exhaust, YT Cam, Stage 2 shift kit, 19psi pulley, 3.73 lsd, 2800 stall, FIT A2A cooler, LS1 Throttle Body, mafless tuned by Turbo Industries (Zeep + VSII_super6)
Tyres - Full Slicks
Weight - 1610kg
Time - 12.619 (PB - 13.749)
MPH - 106.79 (PB - 99.33)
60ft -1.723 (PB - 1.916)

13 Name - David van der voorden (davo_94)
Car - vt Calais
Mods - fmic 1;91 rockers, head work removed balence shaft. pacemakers hiflo cats, redback exhaust Custom Tuned by DICKS ELECTROINCS
Tyres - mt street
Weight - 1591kgs
Time - 12.679
MPH - 104.82
60ft - 1.708

14 Name - Matt Jones (Gigantor)
Car - VT S1 Calais
Mods - 61mm pulley, pod, ls1 throttle body, intermediate cooler, 3.46 lsd, 1 3/4 pacmakers into 2.5" hiflow cats into FIT 3", ported Lim & Blower, intense S1X cam.
Tyres - MT street radials
Weight - full minus jack, spare.
Time - 12.666
MPH - 107.58
60ft - 1.783

15 Name -Elias (elias_vt)
Car - vt super 6
Mods -crow custom grind, 64mm pulley, 1.6:1 rockers,ported blower/u bend, w2a, ls1tb and mafless
Tyres - Mt et streets
Weight - more then 1650 kg. took out cats but left the rest of exhaust on
Time - 12.73
MPH - 107 mph
60ft -1.70

16 Name - hayden (78torana)
Car - UC torana
Mods - Xp hot cam, 3.25 pulley, 3 inch zorst, 1 5/8 HM headers, thrashed out LSD that goes singo everytime lol
Tyres - everyday tyres on car, nexen F 205/50/16 R 245/45.16
Weight - 1333kg (weighed it at the drags with seat in still, no driver) headlight and front seat removed.
Time - 12.746 (PB - 13.27)
MPH - 107.91 (PB - 103)
60ft - 2.011 (PB - 2.1)

17Name - Barry (Decicrate)
Car - VS S Pack
Mods - Yella Terra ToT W2A, Yella Terra Snout with 64MM pully, Ported Blower, Ported LIM (Chipcontrol) Ported Heads, Removed Balance bar, double row timing chain, Diamond forged pistons, Dean Tighe custom cam, linished rods, fully balanced ARP studs and bolts all round.
Gearbox - T56 Road Race Box
Diff - LSD 3.08
Tyres - Kumho V70A track tyres
Weight - 1380KG i think
Time - 12.974
MPH - 106.82
60ft - 1.931
330ft- 5.427
660ft - 8.353
MPH - 84.17
1000ft - 10.855

18 Name - Owen (OFACE)
Car - VT S Pac
Mods - S1X, heads, 1.7, 2.9" pulley, Std LSD, Exhaust
Tyres - half bald street tyres at 35 psi
Weight - took out spare + jack removed one headlight
Time - 13.256
MPH - 107.1
60ft - 2.209

Was looking at the S/C bin (CXWK and CXWH) today, the open loop target AFR tables are most likely part of why your seeing knock on lean cruise and regular cruise compared to the NA version. Might be worth getting some more closed loop values in there instead of the ~16 AFR numbers - have a look at the NA version as thats more how you would expect it.