Weird (?) Dyno Results, 4-banger, Can this be legit? |
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Weird (?) Dyno Results, 4-banger, Can this be legit? |
MikeInMunich |
Jan 1 2015, 07:48 AM
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#1
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Member Group: Members Posts: 392 Joined: 19-November 13 From: Munich, Germany Member No.: 16,674 Region Association: None |
Can a few of you veterans out there please offer feedback regarding this dynograph?
This is new to me, but I am skeptical here. (IMG:style_emoticons/default/confused24.gif) Thanks! Mike in Munich Attached thumbnail(s) |
Dave_Darling |
Jan 17 2015, 12:05 PM
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#2
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914 Idiot Group: Members Posts: 14,991 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
There is no "optimum" AFR. The 14.7:1 is best for complete burn while keeping catalytic converters happy, but it is not the single and only best ratio.
Our engines seem to like to be a bit richer, especially while accelerating. On the order of 12-13:1. Cruise can be 13-14.7 or so, and idle can be whatever it needs to be to get the 3% CO reading and an idle that doesn't hunt. Different octane numbers don't really change the preferred mixture for any given set of circumstances. I agree with the above comments about finding a different tuner. Someone doesn't appear to know WTF they're doing... Your power levels appear to be at least in a reasonable ballpark over all, if a touch low for a 2056 with a stock cam and such. Though the power dropping off so quickly does not seem quite right. That said, you can drive around at or under 4500 RPM all day. Most of us don't get over 5K on a daily basis, I don't think. --DD |
MikeInMunich |
Jan 17 2015, 12:17 PM
Post
#3
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Member Group: Members Posts: 392 Joined: 19-November 13 From: Munich, Germany Member No.: 16,674 Region Association: None |
There is no "optimum" AFR. The 14.7:1 is best for complete burn while keeping catalytic converters happy, but it is not the single and only best ratio. Our engines seem to like to be a bit richer, especially while accelerating. On the order of 12-13:1. Cruise can be 13-14.7 or so, and idle can be whatever it needs to be to get the 3% CO reading and an idle that doesn't hunt. Different octane numbers don't really change the preferred mixture for any given set of circumstances. I agree with the above comments about finding a different tuner. Someone doesn't appear to know WTF they're doing... Your power levels appear to be at least in a reasonable ballpark over all, if a touch low for a 2056 with a stock cam and such. Though the power dropping off so quickly does not seem quite right. That said, you can drive around at or under 4500 RPM all day. Most of us don't get over 5K on a daily basis, I don't think. --DD Thanks for your input here Dave. Apparently I was wrong in my post about the blue line being too lean. According to what you say here the lower numbers are more rich and higher is more lean. I was assuming it was the other way around. What do you think about the timing advance? Should it, IYO, be more than 5° advanced? M.i.M. |
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