egale mark, have you tried a 16144288 ecm in your suburbun? i have been tunning a747 on my 6cylender and after tooning it 1 mpg more than the 288 that has a stock chip. there is not as much stuff that you can change but some one that noos more than me may get a lot of mpgs out of this { rage doll ecm } mine is a 6 an 8 is easyer to get what you need.
i am slow and i for got to say tunning the 747 got 3 more mpgs an it run better than it did with the stock aksf chip. been having fun tring to get mpgs and keep the polution standards for this crazzy truck, most things have been changed but not the wiring horness. i noo what works for mine might not work for yours, but if your bored trie a 288 ecm you might add more mpgs than we noo.
What?
The man who says something is impossible, is usually interrupted by the man doing it.
I agree. What? You lost me...
They are the same ECM except the 7747 has a removable netres/LH chip and the 7747 has a much more refined mask/XDF/bin definition so there's a lot more available. Lots should not be touched.
Tell us what you tried? What worked ? What didn't?
I don't like any 6 cylinder bins as they are all Async fueling. I don't like most 7747 bins as they are Open Loop idle or seem to be OL way to much. I seem to do well with ASDU for all including BB and 6 cylinders? Maybe just used to it?
I've never worried about emmissions...
Things that work for me after mechanics are in order:
1. VE fuel correct.
2. Add timing, find knock and back out 4 degrees.
3. Increase DFCO RPM and MAP range.
4. Increase DE percent.
5. HiWay Lean Cruise.
6. Work on Hiway Lean Cruise spark advance by watching MAP lower.
7. Less Closed Loop timer to enter CL sooner.
8. Less choke.
What I have been wanting to do but have yet the time is change Stoich. Fuel now is mostly 10% ethonal and stoich is 14.2 and not 14.7. But changing Stoich only does not help CL, must change O2 Initial and O2 Rich and Lean points. But should we go to stoich of fuel or should we go leaner AFR? There is very little room for this with a narrow ban O2 sensor to be accurate so I need to put the wide band back in Suburban for testing and it's in my 98 Silverado Vortec truck which I am giving up on stock PCM and swapping in a 0411 LS PCM... Since I get way better fuel milage from a 7747 then I can get out of Vortec PCM... but then the Vortec PCM mask is missing lots of stuff! The 0411 LS PCM is well developed.
This may be a good thread to start the MPG tweaking!
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
You understood what he posted? I couldn't even make what he was traying to say.
The man who says something is impossible, is usually interrupted by the man doing it.
Sort of had an idea because of talking with him before, but my first sentence wasOriginally Posted by Six_Shooter
I agree. What? You lost me...
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
was saying that i was wondering why the 288 ecm was getting 18.3-5 mpgs without being tuned an my 747 was getting 19.5 after being tuned, the 747 runs like a small v8 .the name i chose for the 288 could have been better, the reason i called it a rage doll in tuner pro there is not as much as you can change compaired to the 747 ecm, but with little to offer it preforms pretty well. the mileage on the747 ecm came up about 3mpgs the way i drive after tunning and i am not done yet. if i can figure out how to post i post my bin you may see some where to add more mpgs. for some reason a cannot get the high way cruise reinabled, i had it working on one chip.
HiWay Lean Cruise patch is not applied to the bin posted.
No one has put the work needed into the mask/XDF for the 288, it's not that popular and can plug in a 7747 which is well built mask/XDF.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
I added a couple things to a 288 XDF, when I was tuning a guys truck, but then went to the '7747 because it was a direct plug in and much more defined.
The man who says something is impossible, is usually interrupted by the man doing it.
iam smoothing out the ve table now and going to try again to aplly the cruise patch, if the wind stops blowing going to go down interstate 45 can run 75 mph good place to try things out that has high gearing.
Just make sure the VE is correct/in ball park before enableing lean cruise. Double check data when done. CAREFUL! Don't want to end up to lean in Open Loop/Lean Cruise. The 4.3L with low gears will be working hard. If you have a normal highway cruise speed then allow it to come on just before.
My Suburban, although as aerodynamic as a brick has 5.7L. I was surprised there was not that much difference in load/MAP between 50 and 75 MPH. Around here I do a lot of backroad 50 MPH so I enabled at 45 MPH with a 30 second timer... But it also has 3:73 gears and stock 235/75-15 tires. I have some mountain pass's nearby and used them as a testing ground for HiWay Lean Cruise MAP setting to disable at 75 MAP to pull hills.
Here's the AFR I use with added 3.16 spark, should really be more graphed as leaner needs more timing. Never pushed it any further. MPG is 15% better then EPA sticker average of the vehicle which is 16 highway, I get 18 to 19... and most vehicles never get EPA average so it may be better then 15%?
15.10
16.10
16.10
16.10
15.90
15.70
14.70
14.20
14.00
If you have a pickup truck with open bed do a test of MAP with tailgate up and one with it down? Years ago (1988) I picked up 1 MPG with tailgate down on my first EFI vehicle, a 1987 Chevy Silverado 5.7L TBI short bed 2wd truck. Long before I had any data testing.
But now I have a 1998 Chevy Silverado 5.7L Vortec engine in a Silverado short bed exteneded cab and had some data without a tonneau bed cover and with cover and MAP went down 5KPA on highway so there is some proof to that.
Surprising note is both the 1987 truck and 1990 Suburban with 1227747 ECM got better fuel milage then 1998 Vortec truck and the Vortec truck gets the same as everyone else... well I tweaked a little more but still only up to 16 to 17 MPG highway... no lean cruise available is main reason for the 0411 LS PCM swap upcoming.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
eagle mark, i never did have the lean cruise enabled, only thought i did. worked about 4-5 hours trying to get files into the command prompt folder got every thing set pressed enter [cannot open aksf.bin] .i just dont know enough about pcs to get every thing going. i think it would work well for the way i drive. changed the % of the egr a little on my last program the map stays below 80 kpa driving normal probley could set map around 76-78 kpa.
Been awhile since I used it but think the bin has to be in same folder with program files.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
Hey Mark can you just add some items (constants/tables) into the .xdf with directions on how to enable the lean cruise, like how I have the E-fan stuff put into the $0E? Ya know the same way we change datastream outputs? Then no confusing third party software, and it's easy to change.
1978 Camaro Type LT, 383, Dual TBI, '7427, 4L80E
1981 Camaro Z-28 Clone, T-Tops, 350/TH350
1981 Camaro Berlinetta, V-6, 3spd
1974 Chevy/GMC Truck, '90 TBI 350, '7427, TH350, NP203, 6" lift, 35s
I thought of that but never followed up as to what was exactly changed with that patch, IIRC it also moved stuff? It does Lean Cruise and ESC test done. Difference tool would show 55 byte changed so not as easy as others you did and helped me do.
After I got the patch running I did all the bins I needed and saved them... but now I lost them in laptop crash of 2012 and corrupt DVD backups... so may look into it again.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
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