J
jgw50
Well-known member
OK, no responses on my post below, so i'll simplify:
What A/F is safe to run midrange RPM not on boost?
If my sled runs really good midrange at 15 - 16 A/F, and pretty poorly at 14, am I going to burn down?
What A/F is best to run on 10 lbs of boost?
Thanks!
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2005 M7 stock motor, BD turbo, BD box
At idle it only runs right reading A/F of about 15.5 -16, and if I fatten it up, it gets really blubbery. Once the clutch is engaged, runs 13.5-14 perfect until the M7 lean spot around 5500 RPM and then runs about 15.5-16 again. Then boost hits and it seems it doesnt matter what the A/F is, it just runs and pulls HARD. I run it about 11.5 under boost.
First question is, I can affect A/F with the BD box at idle, but it doesnt run right. Will running that lean at idle and before clutch engagement hurt anything? I've heard some people say you cant burn down at idle no matter how lean, while others have reported that they have.
Second question is, I cant tune that lean spot out of the mid range no matter what I do with the BD box. I can increase the 5000 rpm mid and high so much that it just blubbers and falls on its face, but if I get it to go 5500, it goes lean for a while. Anyone found a fix for that?
Third, My throttle response and "lag" are much less if I run 13.5 -14 A/F up to 5500 RPM, then it runs about 15.5-16 up to 6300 then boost really hits and in run 11.5. Is being that close to stoich (13.5 -14) bad at the lower RPM's? I don't care about fuel consumption or anything else, but it really makes the sled more rideable having crisp lower RPM response and running 12-13 A/F in that region makes it much more blubbery.
Fourth, What A/F is best under boost? I feel like i can go leaner, but the extra fuel makes me feel all warm and fuzzy and there's plenty of power.
WOW, long post with 3 long questions, anyone care to take a crack at it? I know Product tester would say buy a pure logic box and have him put a new fuel pump in and injectors in the throttle bodies, and believe me, i'm saving my pennies, but for now I need to make this boodocker run!
What A/F is safe to run midrange RPM not on boost?
If my sled runs really good midrange at 15 - 16 A/F, and pretty poorly at 14, am I going to burn down?
What A/F is best to run on 10 lbs of boost?
Thanks!
============================================================
2005 M7 stock motor, BD turbo, BD box
At idle it only runs right reading A/F of about 15.5 -16, and if I fatten it up, it gets really blubbery. Once the clutch is engaged, runs 13.5-14 perfect until the M7 lean spot around 5500 RPM and then runs about 15.5-16 again. Then boost hits and it seems it doesnt matter what the A/F is, it just runs and pulls HARD. I run it about 11.5 under boost.
First question is, I can affect A/F with the BD box at idle, but it doesnt run right. Will running that lean at idle and before clutch engagement hurt anything? I've heard some people say you cant burn down at idle no matter how lean, while others have reported that they have.
Second question is, I cant tune that lean spot out of the mid range no matter what I do with the BD box. I can increase the 5000 rpm mid and high so much that it just blubbers and falls on its face, but if I get it to go 5500, it goes lean for a while. Anyone found a fix for that?
Third, My throttle response and "lag" are much less if I run 13.5 -14 A/F up to 5500 RPM, then it runs about 15.5-16 up to 6300 then boost really hits and in run 11.5. Is being that close to stoich (13.5 -14) bad at the lower RPM's? I don't care about fuel consumption or anything else, but it really makes the sled more rideable having crisp lower RPM response and running 12-13 A/F in that region makes it much more blubbery.
Fourth, What A/F is best under boost? I feel like i can go leaner, but the extra fuel makes me feel all warm and fuzzy and there's plenty of power.
WOW, long post with 3 long questions, anyone care to take a crack at it? I know Product tester would say buy a pure logic box and have him put a new fuel pump in and injectors in the throttle bodies, and believe me, i'm saving my pennies, but for now I need to make this boodocker run!
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