4” Down-Pipe – Resonator Question
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Joined: Dec 2003
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From: Stuttgart, Ar
Originally Posted by Choctaw Bob
I recognized the symptoms from first hand experience!
inability to bend arms at the elbows from extreme abuse
surgery scars from elbow repairs.......
"popeye" biceps from overly frequent repetitions
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Joined: Aug 2004
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I just put a 4" exhaust system from the tubo back and have an incredibly abnoxiously loud whistle as the turbo spools up. I was told that the pre October 2003 manufacured 6.0L's were known for this whistle and addressed by Ford when they were built. To cure the problem Ford installed a resonator (heat wrap as it was explained to me) in the factory downpipe to eliminate (or minimize) this sound. After October 2003 Ford began installing an improved turbo that cured the whistle issue and eliminate the need for the factory downpipe resonator. If you want the whistle and your truck was built after 10/03 I will trade you Turbos. I don't like the whistle and am now looking into installing the Banks downpipe with resonator to the tune of $300.
Postmaster
Joined: Aug 2003
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From: Central Texas
Sil307, yep, in 04 engines, they put 3 more "variable vanes" in the turbo. There are also issues that have to do with exhaust back pressure. There is a back pressure sendsor that feeds info to the PCM for control of the VGT. If you start mucking with the exhaust, you sometimes get undesireable results.
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From: Dallas
Originally Posted by SBV45
Sil307, yep, in 04 engines, they put 3 more "variable vanes" in the turbo. There are also issues that have to do with exhaust back pressure. There is a back pressure sendsor that feeds info to the PCM for control of the VGT. If you start mucking with the exhaust, you sometimes get undesireable results.
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Elder User
Joined: Nov 2003
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From: Bass Lake, CA
bah, you guys just need lift kits..... easy to get under mine!
now, getting under the hood for the topside work, that is going to be a pain!!!! i cannot even check my oil without standing on a tire, or a chair.....of course, fords 6' long flimsy dipstick is partially to blame
now, getting under the hood for the topside work, that is going to be a pain!!!! i cannot even check my oil without standing on a tire, or a chair.....of course, fords 6' long flimsy dipstick is partially to blame
Postmaster
Joined: Aug 2003
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From: Central Texas
Originally Posted by Sil307
I'm new to this deisel stuff. What's "VGT" and how will it effect the performance?
Now, if you don't have enough exhaust back pressure because the exhaust is flowing out the exhaust too fast, you don't get your vanes open enough for full operation of the turbo.
That is a simplified answer. Similar to a tuned exhaust on a gasser.
The only flaw with this theory is where is the exhaust pressure sensor located? Pre-turbo or post-turbo? Sorry for rambling but I was just thinking through the flow and events.
Do we have an engineer to jump in?
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From: Dallas
The sensor is located pre turbo so the turbo itself is the primary source of backpressure. Backpressure is just one of the factors, some others are throttle position, load, rpm and so on. The only way to prove an improvement would be to have dyno runs done before and after exhaust installation all in the same week with temperature, humidity and engine temperature all the same.
Postmaster
Joined: Aug 2003
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From: Central Texas
Originally Posted by Choctaw Bob
The sensor is located pre turbo so the turbo itself is the primary source of backpressure. Backpressure is just one of the factors, some others are throttle position, load, rpm and so on. The only way to prove an improvement would be to have dyno runs done before and after exhaust installation all in the same week with temperature, humidity and engine temperature all the same.
Bob, that makes sense, but physically where is the EPS? Maybe someone has pictures? PSD 60?
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From: Dallas
Originally Posted by SBV45
Bob, that makes sense, but physically where is the EPS? Maybe someone has pictures? PSD 60?
Postmaster
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From: Central Texas
I am looking at page 58 and turbo and the diagram doesn't show exhaust ports or turbo. It is an electrical diagram showing relationship between the EP sensor, PCM, FICM, fuel quantity timing and control, malfunction lamp, EGR and VGT Control Valve.