why does power curve get bumpy after 5,200 (centri blower)
#21
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The low hp run was filter on, the high hp run was filter off actually. The Dallas Performance inlet seems to be doing a pretty solid job. It looked grey and dirty compared to new, so I figured I'd pull it and see if it was part of the problem while I was on the dyno.
One other thing I forgot to mention - I'll have to test to make sure, but unless my closest station switched to E85 lately, this pull was also on E70 fuel w/ the E85 tune in. Timing advance is the same betwen the two tunes, it just has fuel tweaks (hence running rich here).
I'm also on the stock plug wires, just with the metal boot things pulled off.
I need to get w/ my tuner to get an E70 map done anyways, so I'll swap the plugs and check some logs and then hit the original dyno and see where it's at.
One other thing I forgot to mention - I'll have to test to make sure, but unless my closest station switched to E85 lately, this pull was also on E70 fuel w/ the E85 tune in. Timing advance is the same betwen the two tunes, it just has fuel tweaks (hence running rich here).
I'm also on the stock plug wires, just with the metal boot things pulled off.
I need to get w/ my tuner to get an E70 map done anyways, so I'll swap the plugs and check some logs and then hit the original dyno and see where it's at.
#23
10 Second Club
iTrader: (14)
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Your Dyno guy needs to give you the numbers in SAE and Smoothing set on 5. Stick with the AFR you're seeing in your wideband, not the tail pipe sniffer. 10.6 is pretty rich.. I went from 10.6 AFR to 10.9-11.0 AFR and it gained 40rwhp. So maybe your tune is getting off some how, maybe the O2 sensors are getting wacked..
In theory, SAE will correct the numbers (to a degree) for crappier weather etc etc.. Yes you'll make more power in better air, but you'll have less correction factor adding in to the numbers so they should always be similar..(assuming same Dyno and SAE correction.
In theory, SAE will correct the numbers (to a degree) for crappier weather etc etc.. Yes you'll make more power in better air, but you'll have less correction factor adding in to the numbers so they should always be similar..(assuming same Dyno and SAE correction.
#24
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STD and SAE both correct for weather, just to different degrees, hence the STD numbers being higher than SAE. Most dyno shops around here use STD with smoothing 3 it seems like for better numbers, so I just roll with that to keep it consistent and not always have to check and swap the correction before printing.
SAE j1349 correction:
29.23 in/hg.
77 degree temp
0 percent humidity
Standard correction:
29.92 in/hg.
68 degree temp
0 percent humidity
SAE j1349 correction:
29.23 in/hg.
77 degree temp
0 percent humidity
Standard correction:
29.92 in/hg.
68 degree temp
0 percent humidity
#25
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Forgot to update, it was the plugs. Went back to the dyno and it made the power back and was smooth. Guess I'll just have to change them out every 1,500 miles or so.
#27
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Already threw them out unfortunately... they all looked good though, maybe a touch rich looking at the base ring. It's the same plugs I used since the first start up, so they've been through the break in, 1st real tune, couple race events, and lately had been run on E70 w/ the E85 tune ~mid -10's:1.