Pettit Racing’s Forced Induction System
#1126
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Good rule of thumb but also dependant on what is upstream of the maf.
If there are maf problems I'd suggest trying to lengthen the scace between the filter and maf, using a straightening screen, and or incorporating an airhorn or one of the filters on the market that includes air straighteners (i think apexi has something like that off the top of my head)
#1127
Finally Boosted!!!!!!!
Maybe, but there is no way I'm putting an air horn on my setup. I plan on using a screen at the mouth of the MAF tube if necessary but I was hoping that by choosing the proper length and size for the MAF tube that I would not need it.
#1128
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As r0tor notes, what happens before and after can affect what the MAF sees.
Necking it down before the MAF with a smooth transition will have a less adverse effect than dropping the diameter afterwards.
#1129
Finally Boosted!!!!!!!
#1130
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I think the revi pipe/filter/horn can be made to fit. and run one screen .I think I am headed that way.
WHo all have widebands(MM I know you have). I am installing one VERY soon--recommendations? Innovate? Summit wideband, AEM? What values are Pettit people seeing?
Anyone heard of Rick Engman?
oscd
WHo all have widebands(MM I know you have). I am installing one VERY soon--recommendations? Innovate? Summit wideband, AEM? What values are Pettit people seeing?
Anyone heard of Rick Engman?
oscd
#1131
Power!!
Length from the inlet to the outlet with the MAF centered and perpendicular to the flor.
As r0tor notes, what happens before and after can affect what the MAF sees.
Necking it down before the MAF with a smooth transition will have a less adverse effect than dropping the diameter afterwards.
As r0tor notes, what happens before and after can affect what the MAF sees.
Necking it down before the MAF with a smooth transition will have a less adverse effect than dropping the diameter afterwards.
#1133
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I think the revi pipe/filter/horn can be made to fit. and run one screen .I think I am headed that way.
WHo all have widebands(MM I know you have). I am installing one VERY soon--recommendations? Innovate? Summit wideband, AEM? What values are Pettit people seeing?
Anyone heard of Rick Engman?
oscd
WHo all have widebands(MM I know you have). I am installing one VERY soon--recommendations? Innovate? Summit wideband, AEM? What values are Pettit people seeing?
Anyone heard of Rick Engman?
oscd
#1137
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I wonder if all major brand widebands are sorta created equal? AEM, Innovate, Auto Meter, Summit ,NGK etc.
Summit (about 45Miles from my home) has a digital readout wideband (bosch sensor) for $249--software etc-- all are included. looks like the Innovate one.
What a/f's are yall seeing?
oscd
Summit (about 45Miles from my home) has a digital readout wideband (bosch sensor) for $249--software etc-- all are included. looks like the Innovate one.
What a/f's are yall seeing?
oscd
#1138
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All of the above WBO2S use the Bosch LSU4.2, 5-wire sensor.
So, it just comes down to features and accuracy of the driver "box".
FordMuscle compared the Innovate LM-1 (which is what I use), AEM, Dynojet, FAST, FJO, NGK, PLX & Zeitronix units against each other. The LM-1 came out on top.
The Autometer is pretty much just for show - its calibration routine sucks and they've been shown to be as much as a full point off in either direction from day to day in different ambient conditions.
I've got more than a couple of posts with details on what your target A/Fs should be.
So, it just comes down to features and accuracy of the driver "box".
FordMuscle compared the Innovate LM-1 (which is what I use), AEM, Dynojet, FAST, FJO, NGK, PLX & Zeitronix units against each other. The LM-1 came out on top.
The Autometer is pretty much just for show - its calibration routine sucks and they've been shown to be as much as a full point off in either direction from day to day in different ambient conditions.
I've got more than a couple of posts with details on what your target A/Fs should be.
#1139
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I wonder if all major brand widebands are sorta created equal? AEM, Innovate, Auto Meter, Summit ,NGK etc.
Summit (about 45Miles from my home) has a digital readout wideband (bosch sensor) for $249--software etc-- all are included. looks like the Innovate one.
What a/f's are yall seeing?
oscd
Summit (about 45Miles from my home) has a digital readout wideband (bosch sensor) for $249--software etc-- all are included. looks like the Innovate one.
What a/f's are yall seeing?
oscd
ive got my sensor on the mid pipe up front..
are all autometers create equal?
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#1143
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The OE wide-band is a bit non-linear at the rich end. It tends to read progressively less rich than reality below 11.5:1 or so.
Plus, you can't datalog it without dealing with the CAN bus stuff.
A nice voltage output is an excellent thing to throw at your engine management.
If and when your flash programmer becomes viable, then it will be a whole different can of worms.
Until then, the OE sensor is just a curiosity.
#1146
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#1149
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I would LIKE to think not - but Jeff can be annoyingly; maddeningly; emptying-my-wallet-y accurate! HAHA
I will log them both as inputs off the same Bosch sensor and run it through my software to see if
1 - They are close
2 - They are off; but a consistent amount
3 - The behavior is so random as to not be predictable
If it is either 1 or 2; they you can decide whether to live with it or not - if it is three; then I will for sure be taking mine out.
I will log them both as inputs off the same Bosch sensor and run it through my software to see if
1 - They are close
2 - They are off; but a consistent amount
3 - The behavior is so random as to not be predictable
If it is either 1 or 2; they you can decide whether to live with it or not - if it is three; then I will for sure be taking mine out.
Last edited by Kane; 01-25-2008 at 06:50 AM.
#1150
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From my fluid dynamics days a good rule of thumb for fully developed laminar flow in a pipe is a Length to Diameter ratio of ~8:1. Based on that to get smooth flow across the MAF sensor (I assume this would be the most accurate) in a 3" pipe you would want 24" ahead of the MAF. That's probably why the screen is there, to artificially smooth out the flow ahead of the MAF since 24" is a bit impractical.