So maybe the issue I am having is that (besides not having access to that table) I am running a Baro sensor breakout and an LS9 map sensor, giving me (and the ECM) a real pressure ratio.....
If most people keep the stock MAP and run a stock VVE setup, will the computer not always see a maximum of 1.0 PR? Damn maybe I made the wrong move, thinking I was doing it the right way. That might be tomorrow's project....Stock map sensor.
HPT, can you open up this table?
Thanks, Road!
I just maxed these tables out as well, I thought making the P0068 disabled under 10K RPM would do it, but maybe these tables are the cause? They max out at 68 though....
P0068.jpg
I'm not so sure the knock sensors actually "hear" knock at all, whether it be real or false.
You can command 10* of timing and get 10* of retard with high octane fuel. There is no way the sensors could actually be picking anything up.
I wonder if the PCM looks at load, airflow, etc. and just figures is "should" be knocking so it throws a bunch of KR in. Although that still doesn't answer the question as to why you can get 5* of knock retard but still have exactly what you commanded in the first place. What, if anything, does the KR actually do?
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post your file please wat SOI values ur using u have ipw of 10msec at 5500 RPM which means ur injector will stop injecting 20BTDC therefore if your timing adv is 20 degrees u might be spraying fuel on ur spark......keep in mind this calculations does not take into account chamber design and all other factors.
Last edited by jarrah; 09-14-2015 at 03:58 AM.
keep in mind the ecu has other factors based on EOI therefore the ecu looks into your SOI angle back calculates the desired IPW based on that it will look at your timing tables sees if it is possible to run this timing if not it will cut the timing to allow combustion to happen and this is exactly what is happening in your case ecu sees its not possible to run this adv otherwise it will be spraying fuel on ur spark .......check under fuel there is EOI max which allows a max of 10 deg BTDC and there is another EOI Low pressure.
I have seen bad MAF sensors cause some crazy fueling problems (These new style MAF) to the point that it has made me think there is a fuel supply issue. (Not saying yours is bad). But when the MAF-MAP-BARO correlation is off I would think it would only reason to affect the fueling. Personally I think your fuel setup should work. As Dstech has stated the baro break out will allow you to tune the VE coefficients. This brings the thought that after the ve is correct would it be better to use the stock MAP sensor to limit pressure ratio to @ 1.05 then that will let the MAF not limit?Originally Posted by Higgs Boson
Happy Tuning lol
Mike
Exactly!
IPW goes to 10 when the pump loses pressure and it works overtime to try and fuel the airflow. It is 4.5 or so just before it shoots up to 10. under full load I have adjust my SOI from stock (335) to 360 to now around 450. the higher values have bought me maybe an extra 1000 RPM.
Commanded Spark is 12 (sometimes 8 if the knock retard makes me nervous). I am for the most part getting commanded. Since it's a Flex tune, final spark is usually a little higher than that though.
SOI in the problem area is 400 to 460.
EOI Spark Offset is 5
Commanded Spark is 12-17 (E0 - E85) currently 12/13 on E37
EOI Low Pressure is 200 (should I lower this value to 5 also?)
At 1.0 g/cyl and 3000 RPM my SOI is only 360, just above that is where the fuel pressure starts to go away, SOI is in the 380s.....you might be onto something because when it gets past 5000 or so it is lean and there is no pressure but it suddenly blasts off with power.....SOI is 430+.....so maybe I should make it 430 to 460 all the way down to 3000 RPM and 1 g/cyl??
I am going to explore this after more SOI/EOI changes.....I am going to change SOI to 460 much lower and see if it cleans up. This might be the reason for my troubles, my exhaust tips are black which would make sense if I am spraying fuel on my spark! It sure runs like crap in the mid range as well (full throttle). Part throttle it is a beast (sounds weird)!
Yes do that set at 3000rpm 1g/cyl to 430 and under fuel sys increase pressure for both pumps and under variable cam aet ur wot to 4 i need to see the tune to be able to help
Check out this log:
This is with 355 SOI in the high load area.....I had set it to 460 as planned and it wouldn't even make it over 3000 RPM. Would just cut out and buck so I went the other way with it.
355 SOI.hpl
I still need the extra fuel pump, I think that is my biggest problem right now.
Okay so did u try in the higher loads a value of 430 and did u increase ur hpfp pressure to 25mpa ........try also other settings this shld work i tuned a silverado turbo with this method it had same symptoms ur describing
yes, when I had the SOI at 400+ it would not hit commanded of 25 MPa (has been set at 25 since the beginning), it would only hit about 19 and at 460 it wouldnt even rev over 3000.
at 355 SOI it revs through 3000-5000 and holds 25MPs easily but the tank pump drops from 70 to 45-50 and MPa drops from 25 to 6 and duty cycle goes from 4 to 11.
I don't think there is anything left to do but wait on supplemental pump kit to come in.
The issue with so much SOI timing is that it is a good band aid for lack of fueling, but I have plenty of high pressure fueling (not enough low pressure tank fueling). Therefore, I don't need to pull SOI ahead so much, in fact, I could probably shorten the injection window from 355 even. When I have good fuel pressure to 7000, I will fine tune SOI using DStecks excel file.
I feel like 355 is the most I wanted to advance injection because that is 5 degrees after the intake stroke starts and my exhaust valve closes right before that. At 460 SOI I am just pushing fuel out the exhaust for 95 or so degrees of exhaust stroke, that is over half the exhaust stroke!
If nothing else, moving SOI to 460 helped me realize I was moving in the wrong direction, so thank you for that! ;-)
anytime bro its a matter of testing since your having shortage off fuel pressure in the intank fuel pump its not helping in reality its just a matter of finding or calculating the desired SOI u can build a custom histogram and will back calculate your SIO based on ur timing and IPW this is how I do it.
I will update as soon as I get the second pump installed!
as I said before there r many factors that effects those values u can take into account the opening and closing values for the intake and exhaust valve even on the max EOI u can back calculate wat should be ur IPW and if u exceed that ur blowing spark
what are you guys smoking, anything over about 340-345 SOI (depending on the cam) will cause you to spray fuel directly into the exhaust stroke, how is that going to help anything? Its very easy to calculate how far you could go on the SOI before its not gonna help. Also take into consideration that you will want the fuel to sit on the piston as much as possible BEFORE the spark plug fires to give it enough time to atomize for proper burn. Dont expect to properly light off a high HP WOT fuel mixture 5 degrees after the EOI.
well, i have a new problem anyways.....I have no rail pressure under boost (or over 1.0 g/cyl).
at first it was dropping tank pump pressure and the rail pressure slowly declined.
now I have good tank pump pressure (because I am dropping rail pressure).....rail is going from 11.7 straight to 5, 4, 3 MPa when I lay into it.
Any ideas? Nothing in the tune I can find....possibly a leak? Maybe a blown fuse? It does go right back to commanded pressures when I go back to part throttle.....
Anyways, my exhaust valve closes 5 degrees before TDC so in theory I could start injection as early as 365 without worrying about spraying out the exhaust, right? Due to the above issue, I can't even get over 4000 RPMs anyways.
Did u try putting back stock map sensor?
Btw the max SOI is like 513 keep in mind stock cam duration IN 200 EXH 207.....
720-207=513 degrees
no i haven't. it was working fine with the LS9 map so I sort of ruled it out, but at this point anything is possible.
that would just shorten my max to 489.... the exhaust still closes at 365 though.
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