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Ok, so I've reached my wit's end and realize I have no idea what I'm doing as far as tuning goes. I originally posted in the EBL flash tuning thread, but feel like maybe I should start my own thread?
My build is as follows - 383 - 18cc Dish Pistons, Vortec Heads, 54 mm BBC TB, Comp Cam 8-502-8, EBL Flash, Open Air Intake, Vortec Fuel Pump, 90# Injectors (5235231) with 18 psi spring.
I have gone through my VE Learns for the values most driven in for me and they are +-2. With the bigger injectors and higher FP, I've multiplied my AE TPS/MAP PW tables by the new ratio of 0.58 (61/106# = 0.58), as well as both my PRP Gain tables.
I'm also using Fast's SA table from the EBL thread with no knock counts.
She idles great and cruises around town pretty smoothly, but when I hit the go-go juice, it doesn't feel any different than a stock SBC.
Attached are 2 logs for WOT and spirited driving along with my bin.
Any help getting this thing burnin tires up would be most appreciated.
Looks like you at an elevation of about 4000 feet? I was looking at the MAP value and at low RPM and 100% TPS it is 87 - 88 KPa.
Which dropped to 85 KPa at 4400 RPM, which is OK and shows that the intake track isn't much of a restriction.
There is too much AE on the throttle stomp, it goes bloody rich. Can reduce the AE PW tables in the higher deltas. The log file shows in the area of 20 - 40 % dTPS and 20 - 40 KPa of dMAP.
Once the AE burns off the AFR starts to head lean. Hopefully the fuel pressure isn't dropping off. The injector DC% is low (66%) so still have lots of headroom. Although the VE is at 97%+.
So, increase the BPC vs VAC table by 15%, and reduce the VE table(s) by the same 15%. You can now add more WOT fuel to the VE table(s).
> Open Air Intake
This is going to make tuning difficult as the weather changes so will the fueling.
Any help getting this thing burnin tires up would be most appreciated.
Just looked at his wide open throttle pull. Looks like the timing is coming in too late and is also a little low, your cam's RPM range is between 1500-5500 RPM, and your spark advance is only 30* at 3000-RPM, and 31* at 4475-RPM. That is very conservative...
There is too much AE on the throttle stomp, it goes bloody rich. Can reduce the AE PW tables in the higher deltas. The log file shows in the area of 20 - 40 % dTPS and 20 - 40 KPa of dMAP.
What AFR am I shooting for while in AE and not quite PE?
Just looked at his wide open throttle pull. Looks like the timing is coming in too late and is also a little low, your cam's RPM range is between 1500-5500 RPM, and your spark advance is only 30* at 3000-RPM, and 31* at 4475-RPM. That is very conservative...
And shifting too soon, but until there is more fuel it is better that way.
What AFR am I shooting for while in AE and not quite PE?
When not in PE mode I look at the INT to see if it rises a bit, just a couple of points. If it drops on AE then there is too much. As the AE runs out the falling INT can create a lean bog until it recovers.
Why 90# injectors? Did I miss a gigantic turbo? That's causing your headache. Sounds like you aren't fully tuned for them and I don't see why you'd ever run that size injector especially when you're creating this problem.
I'm running a TBI, so with the HP goals I was looking for, 90# injectors are what I'm looking at as long as I can get my idle down. My idle is fine, it's when I want to mash the go pedal that she falls on her face.
I've adjusted my PE SA adder table to increase my SA while under PE and reduced the TPS value needed to engage PE, so that will hopefully help with the SA issue.
I've also reduced my MAP/TPS AE PW tables from 20 - up by about 10%. Going to go take more logs now to see how she responds.
And shifting too soon, but until there is more fuel it is better that way.
RBob.
Very true.
Originally Posted by darksurfer11
I've adjusted my PE SA adder table to increase my SA while under PE and reduced the TPS value needed to engage PE, so that will hopefully help with the SA issue.
Try to aim for your total timing to come in around 2800-RPM during Power Enrichment and maintaining it throughout, but like RBob pointed out, don't aim for 36* right away, work your way up to it slowly, but be sure it comes in by at least 2800/3000-RPM...
I've adjusted my PE SA adder table to increase my SA while under PE
You are flirting with disaster, get more fuel into the engine first. Lean is mean right up until things go south. Get the PE/WOT fuel into the 12.6 - 12.8 AFR range, then play with spark advance.
Ok, I've got 2 more logs, one for OL WOT and one for CL WOT. It looks like on the OL WOT, it doesn't get as rich, but there is a lean spike at the beginning, and on the CL WOT it get's really rich, but doesn't have as much of a lean spike. Am I reading these correctly?
You are flirting with disaster, get more fuel into the engine first. Lean is mean right up until things go south. Get the PE/WOT fuel into the 12.6 - 12.8 AFR range, then play with spark advance.
Ok, I've got 2 more logs, one for OL WOT and one for CL WOT. It looks like on the OL WOT, it doesn't get as rich, but there is a lean spike at the beginning, and on the CL WOT it get's really rich, but doesn't have as much of a lean spike. Am I reading these correctly?
Way too much, bring it down some, as there are areas where you are seeing 40* in that datalog which is way too much with iron heads, even with aluminum heads that is too much. Your total timing needs to be brought in at 2800/3000-RPM, but it doesn't have to be anywhere near 40*. If your total timing for your application is set to be say 34* and no higher, then you want to see 34* come in at 2800/3000-RPM, and stay there at that 34* target all the way up until your highest RPM is reached, never exceeding 34*. The idea is not to exceed 34*, but have it come in at the right RPM, in this case 2800/3000-RPM. This is what is meant by bringing in your total timing earlier. Definitely undo what you did, and if you do it again that way, do it in very light increments targeting no greater than 34* total timing all the way up, and yes, get it richer before messing with the spark advance...
Yes, don't do it that way. I just now realized you were using that method.
Look at your SA Main Table, I provided a picture of it below. Compare it to your extended SA table just below it. Look at it carefully, it doesn't transition smoothly from 4800-RPM and up, the extended tables look like they were left out of the changes you made. Do you see what I am referring to? Not only that, but 2800-RPM is nowhere near being total. You want your total timing to come in at 2800/3000-RPM. I mean realistically speaking all you really need to do is cut and paste the entire extended table from the lower graph into the larger graph above it but only from 2800-RPM to 4800-RPM, leave the lower tables (400-RPM to 2400-RPM) the way they are...
I mean realistically speaking all you really need to do is cut and paste the entire extended table from the lower graph into the larger graph above it but only from 2800-RPM to 4800-RPM, leave the lower tables (400-RPM to 2400-RPM) the way they are...
Like this, the Red is obviously where the changes were made. It brings your total timing in where it needs to be, while maintaining a targeted spark advance, and no greater than that, as RPM increases. You would just need to correct 4800-RPM in the extended to make it match the 4800-RPM in the Main above it if you use this method...
Ok, I've done a bunch of changes on my SA table, and turned off PE SA. I've tried to adjust the AE PW tables, but I still get a lean bog at the beginning of WOT.
Spark Advance looks much better, by 2800-RPM your total timing is being brought all the way in, and by 3000-RPM your right at 34* and maintaining it throughout. As for the lean bog, I can see it between 900-RPM (51 kpa) to 2000-RPM (87 kpa), work that area...
Ok, i've adjusted the AE PW tables a couple times now and here is my most recent log. I don't feel like the changes I'm making are making any differences. Any ideas?
There is a PT to WOT in there and an idle to WOT run. The idle to WOT run is at the end.
Ok, i've adjusted the AE PW tables a couple times now and here is my most recent log. I don't feel like the changes I'm making are making any differences. Any ideas?
Ok, i've adjusted the AE PW tables a couple times now and here is my most recent log. I don't feel like the changes I'm making are making any differences. Any ideas?
You have to pay attention to the area that needs the change. You go lean upon mashing the throttle at 900-RPM up until 2000-RPM, then the fueling catches up to where it needs to be, and then you start to head towards the rich side. In my opinion, before you make any changes you need to fix your VE table. In fact, whenever you do make a change, any change, a VE Learn is mandatory. Your BLM locked at 135 when you entered Power Enrichment, you need to get that down to 127 before that happens. I attached your lower VE graph below, it needs work. Once you sort that out, then you can tune your Acceleration Enrichment in the area that needs it; 900-RPM to 2000-RPM. Tune that VE first, 135 BLM is too high, you want to target 127 BLM just prior to PE. Look at the datalog for reference...
I've gone in and cleaned up my VE tables and increased the VE% in the 80KPa+ range, but I've still got a lean spike followed by being rich at around 11.1 AFR before raising back up the 12.8 after AE is over. Couple questions here:
1. Should I worry about the lean spike right after WoT press?
2. Should I be decreasing my AE once again?
3. When doing VE learns in closed loop and open loop they are within +-2 of 0, I did notice, however, that none of my learns are reaching above 80 KPa, is there a setting I need to adjust?
Thanks for all the help!
Attached is a picture of the lean spike as well as the entire datalog and my current bin.
I've gone in and cleaned up my VE tables and increased the VE% in the 80KPa+ range, but I've still got a lean spike followed by being rich at around 11.1 AFR before raising back up the 12.8 after AE is over...
When you added fuel to your VE table it was meant to maintain a stoich air/fuel ratio just prior to entering Power Enrichment. If you look carefully at the Datalog you will see the target air/fuel ratio being 14.7, but then switch the 12.8 the moment you enter Power Enrichment. The ECM uses the VE fuel as only a base for the Open Loop fuel table, this is known as Alpha N. It (Power Enrichment) calculates 12.8 from the 14.7 VE table, the VE table it is not meant to fix a lean spot at wide open throttle. The lean spot will be fixed with the Acceleration Enrichment table. Your target is 12.8 under Power Enrichment, so when you see 12.8 in the AFR column of the datalog, compare it to your wideband reading, then using the Acceleration Enrichment table add fuel where the wideband is reporting over 12.8, and pull fuel when the wideband is reporting under 12.8. Basing what I am looking at in your new datalog, from a dead stop and then full throttle, you need more fuel between 800-RPM and 1800-RPM, and less fuel between 2000-RPM and 2700-RPM. Look at it, your commanded air/fuel is 12.8 and your wideband is reporting 15.0 between 800-RPM and 1800-RPM, and then as soon as your reach 2000-RPM, your target is still 12.8 but your wideband then reports under 12.0...
When you added fuel to your VE table it was meant to maintain a stoich air/fuel ratio just prior to entering Power Enrichment. If you look carefully at the Datalog you will see the target air/fuel ratio being 14.7, but then switch the 12.8 the moment you enter Power Enrichment. The ECM uses the VE fuel as only a base for the Open Loop fuel table, this is known as Alpha N. It (Power Enrichment) calculates 12.8 from the 14.7 VE table, the VE table it is not meant to fix a lean spot at wide open throttle. The lean spot will be fixed with the Acceleration Enrichment table. Your target is 12.8 under Power Enrichment, so when you see 12.8 in the AFR column of the datalog, compare it to your wideband reading, then using the Acceleration Enrichment table add fuel where the wideband is reporting over 12.8, and pull fuel when the wideband is reporting under 12.8. Basing what I am looking at in your new datalog, from a dead stop and then full throttle, you need more fuel between 800-RPM and 1800-RPM, and less fuel between 2000-RPM and 2700-RPM. Look at it, your commanded air/fuel is 12.8 and your wideband is reporting 15.0 between 800-RPM and 1800-RPM, and then as soon as your reach 2000-RPM, your target is still 12.8 but your wideband then reports under 12.0...
Ok, so adjust the AE tables to increase fuel between 800-1800 RPM and decrease after 2000?
Ok, so adjust the AE tables to increase fuel between 800-1800 RPM and decrease after 2000?
Yes, but do so in increments until you get it just right. Watch the wideband data carefully during those two points, and as the wideband gets closer and closer to 12.8 between 800-RPM and 1800-RPM you will feel that lean bog getting lighter and lighter, until it is finally gone. After 2000-RPM, start reducing the amount of Acceleration Enrichment to raise the wideband data closer to a 12.8 air/fuel, and the engine will pull much better in that area.
For reference, your INT/BLM are columns AJ/AK (they lock at 128, good job finessing the VE), your target AFR is column AN, and your wideband reading is column AO. The moment your AFR (column AN) enters Power Enrichment its' air/fuel target becomes set at 12.8 from 14.7, but your wideband (column AO) which was current with the 14.7 AFR essentially stays at 14.7, it doesn't have enough Acceleration Enrichment to "pump shot" it into the 12.8 zone, so it stays at 14.7 and even gets leaner than that reaching upwards of 16.0. This all happens between 800-RPM when you floor the throttle up until 1800-RPM. It starts to finally catch up by 2000-RPM, but by that time you are already experiencing a lean bog, and after 2000-RPM, the wideband (column AO) starts going rich, even seeing as low as a 10.8 AFR...
For reference, your INT/BLM are columns AJ/AK (they lock at 128, good job finessing the VE), your target AFR is column AN, and your wideband reading is column AO. The moment your AFR (column AN) enters Power Enrichment its' air/fuel target becomes set at 12.8 from 14.7, but your wideband (column AO) which was current with the 14.7 AFR essentially stays at 14.7, it doesn't have enough Acceleration Enrichment to "pump shot" it into the 12.8 zone, so it stays at 14.7 and even gets leaner than that reaching upwards of 16.0. This all happens between 800-RPM when you floor the throttle up until 1800-RPM. It starts to finally catch up by 2000-RPM, but by that time you are already experiencing a lean bog, and after 2000-RPM, the wideband (column AO) starts going rich, even seeing as low as a 10.8 AFR...
Gotcha, am I better off adjusting the RPM multiplier tables, or PW tables?
Gotcha, am I better off adjusting the RPM multiplier tables, or PW tables?
Remember, a properly tuned VE table is the basis for all of your fueling, it essentially becomes an accurate air flow table for the engine. The Acceleration Enrichment compensates with more fuel for the momentary rush of incoming air upon throttle, and this additional fuel is stacked on top of the commanded fuel via the VE table. As for what you are asking, I find that TPS PW based Acceleration Enrichment is much easier to tune overall...
Just want to add one more thing regarding the AE & PE tables in your latest bin, they seem to be very off. By the way which bin did you start with? I am looking at your PE Enable table, and the setting is very low in the low RPM area. Based on your engine's application, I would highly recommend transferring all of the Acceleration Enrichment and Power Enrichment values from RBob's 3001 bin to your own, then after that is done, datalog it again, see where you stand in terms of your AFR when you stab the throttle, and if need be, then make the necessary changes in the locations wherever you may need them...
Just want to add one more thing regarding the AE & PE tables in your latest bin, they seem to be very off. By the way which bin did you start with? I am looking at your PE Enable table, and the setting is very low in the low RPM area. Based on your engine's application, I would highly recommend transferring all of the Acceleration Enrichment and Power Enrichment values from RBob's 3001 bin to your own, then after that is done, datalog it again, see where you stand in terms of your AFR when you stab the throttle, and if need be, then make the necessary changes in the locations wherever you may need them...
I had originally used the 2010 Bin and imported the 3000 spark tables, of which have been completely changed, due to still using the TBI. I've changed the AE and PE tables to match the 3001 BIN and need to do some VE learns as they are off again. Will post back with updated results as soon as this bloody rain stops, haha. Thanks again Street!
I had originally used the 2010 Bin and imported the 3000 spark tables, of which have been completely changed, due to still using the TBI. I've changed the AE and PE tables to match the 3001 BIN and need to do some VE learns as they are off again. Will post back with updated results as soon as this bloody rain stops, haha. Thanks again Street!
I see, you started out with the 2010 bin because it was LO5 based. Allow for those VE Learns using the AE/PE tables from the 3001 bin, and see how she feels. The 3001 bin is based on a 327 running 80-lb injectors, so it should be somewhat close to what you need. That cam in the 3001 bin is extremely healthy, and I am now wondering if this is a bin straight out of RBob's Camaro...
03-23-2016, 08:30 PM
