Thanks I probably should have posted that.Originally Posted by AKDMB
Thanks I probably should have posted that.
The SCT Coyote class that I attended last March, attributed the #8 failure to Fuel Imbalance Monitor.
Did anyone question that or ask exactly how it causes it?
I know in the older cars there were values of 1.03-1.04. I just am not sure if that's multiplying lambda or fuel amount. It could be making it richer if it's fuel amount and removing that could be bad. 1.03-1.04 is a very small amount and I'm not sure if it could make that much of a difference. It's on my list and I haven't counted it out because it does mess with fuel. Just would like to know exactly how?
I have been wondering that myself.
The correction to be made was to increase any value below 1 to 1, in the first 2 rows(which would be last 2 rows in HPT) and above 2k RPM. It was taught that it was a fuel multiplier and any value below 1 was removing fuel. It may be a multiplier to the MAF value.
Just for reference, my Roush tune has every table set to 1, by default.
Ford likes complicated things so it could be the maf. Just not likely as the extra load on the ecu processor from doing speed density equations for each cylinder wouldn't be in a programmers best interest. Going right to the lambda value or an injector value would be considerably less cpu consumption even if it would be less accurate the trade of would be worth it. Those speed density calculations through multiple flow models are no small task for a processor.
Thanks for sharing that info txcharlie
Hmm, I'm not so sure the cause of the failures is related to the fuel imbalance monitor. I have 2 very recent tunes from 2 very respected tuners and neither one touched that table. And I have values below 1 which presumably means the cylinder was removing fuel. I still think the biggest contributor was aggressively using the knock advance limit. I don't doubt the car can get into a very lean condition at WOT for whatever reason, but I'm inclined to think it was an overconfidence in allowing the ECU to advance spark at a much higher than stock rate and then getting into stoich at WOT.
http://www.mustang6g.com/forums/show...&highlight=air
Intresting information in this thread.
"The quote was proved wrong ages ago.
The 4v design has had heat issues with 7,8 and 4 since the creation in 1994. On the Mach1's, the head cooling mod was HUGE!! And even on the coyotes... It's great!! You are dropping temps a good 15* with this crossover. I 100% recommend this. I will be doing it to mine soon too." -UPRsteve
Last edited by murfie; 02-28-2016 at 08:26 PM.
I discussed this with a fellow tuner as to how the values > 1 could be a lean condition. I don't know how the multiplier works and the instructor did not offer any info on the "how", so it's just speculation(like everything else on the copperhead..LOL).
Not a problem! That's why we have this forum.
Hi gents - I would like to revive this threadLong time reader with some experience. S550 Mustang with Long Tubes and Stage 3 Comp Cams - max effort.
I have some issues(more doubts actually) with STFT bank to bank difference - it seems to be the case at high RPM only.
Stage 3 Comp Cams have waay more duration - you can't really bring that setup under 2% like with stock cams.
STFT around 5% are acceptable IMHO - can't tune it better anyways.
Spark is good, MAF is good and everything else seems to be OK - tune is really good IMO. Been hitting 32 degrees with race fuel and I have not yet seen any knock activity above 3000 RPM.
STFT bank.jpg
I've removed all fuel corrections besides fuel imbalance monitor. I think Ford did that due the unequal shorty header design: 4-2-1. Those headers are very compact
but have unequal length, diameter and flow characteristics. I now have Kooks long tube headers which are considered to be more like middle length headers - 4 to 1 setup.
They are almost EQUAL length and I can only imagine each pipe flows almost identically. My dilemma is: do I still need those fuel imbalance corrections?
I'm struggling with the idea of correcting all top end cells to 1 - I've seen a lot of supercharger tunes having ALL cells moved to 1.
STFT are ideal up to 6000 rpm and then they can take different routes - one on plus and other on minus around 5% apart. LTFT are perfectly matched.
As you can see it flows like crazy - MAF almost like in a supercharged engine. I dynod it with over 600 HP crank or over 500 RWHP as you wish.
2gvsx12.jpg
Last edited by veeefour; 12-11-2017 at 05:02 AM.
Some folks delete the environmental and multis, I run them without issues. 464 gms/sec is around 61 lbs/min which is pretty good for an NA engine. My engine normally indicates 78-80+ and is right around 700 RWHP (FI engine at 12-13 psi boost). Personally, I think the environmental values are there for a reason....
2012 Mustang GT with S/C
4Runner with S/C
Turbo/NOS Hayabusa - 320RWHP
My environmental and multis are still there - I haven't "butchered" the tune by just zeroing everything if want to know. They are tweakd accordingly
MAF is high because I have some serious cams. The whole VE model changed - had to redo the torque model. Still not on zero with ETC errors but close enough.
I had to redo the driver demand table as well - IMHO tuning the cams is as much complicated as tuning the FI.
If you do the quick math:
BANK 1:
cyl 1 +3%
cyl 2 0%
cyl 3 -2%
cyl 4 +1%
BANK 2:
cyl 5 -2%
cyl 6 +1%
cyl 7 0%
cyl 8 -3%
Bank to bank: BANK 2 registers 6% less of fuel(-4% to +2%) which is exactly what I can see im my logs.
I went and changed all TOP END(last cells) to 1 in fuel imbalance monitor and did a quick WOT - need to retune the MAF again(which was to be expected).
The main question is do you really need those cylinder offsets if your are running with long tube headers?
Still a slight dip at 8000 rpm but slightly better if you ask me but does it needs to be this way?
better.jpg
Last edited by veeefour; 12-11-2017 at 12:46 PM.
Nothing in that thread said what they were actually doing to prevent the WOT leanout/timing additions etc. I had just posted elsewhere about killing the ecus ability to ADD timing.
Factory Stock 97 SS M6 13.51 @ 104.3 mph
Stock Longblock LS1 w/ 233/238 P.S.I. Cam
10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago
'99 TA trunk mounted 76mm 6 Liter
9.0s in '09 @ 153 MPH
Turbo 5.3 Volvo 740 Wagon
32psi and still winding out 5th on the highway somewhere
Problem solved - bank difference has nothing to do with "enviormentals and multis". It was something else.My environmental and multis are still there - I haven't "butchered" the tune by just zeroing everything if want to know. They are tweakd accordingly
MAF is high because I have some serious cams. The whole VE model changed - had to redo the torque model. Still not on zero with ETC errors but close enough.
I had to redo the driver demand table as well - IMHO tuning the cams is as much complicated as tuning the FI.
If you do the quick math:
BANK 1:
cyl 1 +3%
cyl 2 0%
cyl 3 -2%
cyl 4 +1%
BANK 2:
cyl 5 -2%
cyl 6 +1%
cyl 7 0%
cyl 8 -3%
Bank to bank: BANK 2 registers 6% less of fuel(-4% to +2%) which is exactly what I can see im my logs.
I went and changed all TOP END(last cells) to 1 in fuel imbalance monitor and did a quick WOT - need to retune the MAF again(which was to be expected).
The main question is do you really need those cylinder offsets if your are running with long tube headers?
Still a slight dip at 8000 rpm but slightly better if you ask me but does it needs to be this way?
better.jpg
Please share what solved your issue.
Transport delay - had to increase it a lot, more than some would advise.
Best way to tune it is to log commanded lambda vs actual lambda.
Last edited by veeefour; 01-06-2018 at 03:16 AM.
As for stage 3 comp cams it's super smooth!
smooth.jpg
I had done some transport delay testing on a long tube car about two years ago and did not really know what I was doing. Gave up when I was told just multiply the transport delay table by 1.25 and move on. I still have the data I collected.
Test was at 60mph with cruise set on level road for 3 minutes each. I started with a stock transport delay table an repeated the test by increasing the values by 25% at a time. I can clearly see at the recommended 25% its better than leaving it stock but the short terms swing by 10% to maintain commanded. At 75% the short term swings are only 2%. I have no data for idle or WOT just at speed on highway with cruise set. When you say you ended up with more than normal is this what you had experienced?
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