A/F ratio on dyno.. Comment on this:
#1
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A/F ratio on dyno.. Comment on this:
Some food for thought: dyno AFR will always be about .4 of a point AFR leaner than real life. This is due to the car being still/static rather than dynamic air flow when driving.
The dynamics here are that when you are moving though the air while driving, the MAF will see more air flow than when static on a dyno. This will translate to more pulse width at injector = richer
So basically tune for slightly lean on the dyno, knowing it will richen up with load..
Comments please.
The dynamics here are that when you are moving though the air while driving, the MAF will see more air flow than when static on a dyno. This will translate to more pulse width at injector = richer
So basically tune for slightly lean on the dyno, knowing it will richen up with load..
Comments please.
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Originally Posted by Billiumss
Yes, you are correct, dynos are a tad lean than on the street. They just don't "LOAD" a car like the street does.
I always shoot for a 12.4-12.6 on the dyno when I tune LS1s
I always shoot for a 12.4-12.6 on the dyno when I tune LS1s
#4
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Originally Posted by YO-EL
Some food for thought: dyno AFR will always be about .4 of a point AFR leaner than real life. This is due to the car being still/static rather than dynamic air flow when driving.
The dynamics here are that when you are moving though the air while driving, the MAF will see more air flow than when static on a dyno. This will translate to more pulse width at injector = richer
So basically tune for slightly lean on the dyno, knowing it will richen up with load..
Comments please.
The dynamics here are that when you are moving though the air while driving, the MAF will see more air flow than when static on a dyno. This will translate to more pulse width at injector = richer
So basically tune for slightly lean on the dyno, knowing it will richen up with load..
Comments please.
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But Bill said the dyno is lean...
So I with that premise with load on the street it will richen up..
12.4-12.6 on the dyno would richen up to 12.0-12.2 in his line of thinking right?
Sounds pretty fat to me..
Please correct...
Or, with load on the street, will A/F lean out?
So I with that premise with load on the street it will richen up..
12.4-12.6 on the dyno would richen up to 12.0-12.2 in his line of thinking right?
Sounds pretty fat to me..
Please correct...
Or, with load on the street, will A/F lean out?
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Are we talking about the Dynojet AFR? That always reads about a .5 point leaner than my LM-1 or other handheld logger. That whole suction pump setup seems like overkill and it places the wideband sensor over 10 feet further downstream from the end of the tailpipes.
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Originally Posted by foff667
did u read you own post? "dyno AFR will always be about .4 of a point AFR leaner than real life" meaning if you run 12.6:1 on the dyno your gonna run leaner then on the street by .4 meaning on the street you'd be running 13.0:1 roughly.
On the street you'd run RICHER...
Lean 13.0 --------- Rich 12.0
IF the dyno runs .4 LEANER than the street, that would mean that:
a 12.6 A/F ratio on the dyno (is .4 LEANER than on the street),
so street A/F would be RICHER, 12.2 right?
Again if the dyno is LEANER, with load on the street, the A/F would go RICH.
so, 13.0 dyno to 12.6 street
12.6 dyno, 12.2 street
Right??? Or I am going nutz here?
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Originally Posted by YO-EL
Dude,,, 13.0 is LEANER than 12.6
On the street you'd run RICHER...
Lean 13.0 --------- Rich 12.0
IF the dyno runs .4 LEANER than the street, that would mean that:
a 12.6 A/F ratio on the dyno (is .4 LEANER than on the street),
so street A/F would be RICHER, 12.2 right?
Again if the dyno is LEANER, with load on the street, the A/F would go RICH.
so, 13.0 dyno to 12.6 street
12.6 dyno, 12.2 street
Right??? Or I am going nutz here?
On the street you'd run RICHER...
Lean 13.0 --------- Rich 12.0
IF the dyno runs .4 LEANER than the street, that would mean that:
a 12.6 A/F ratio on the dyno (is .4 LEANER than on the street),
so street A/F would be RICHER, 12.2 right?
Again if the dyno is LEANER, with load on the street, the A/F would go RICH.
so, 13.0 dyno to 12.6 street
12.6 dyno, 12.2 street
Right??? Or I am going nutz here?