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i'm hitting target boost 500rpm late...why?

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Old May 24, 2009 | 09:14 PM
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Default i'm hitting target boost 500rpm late...why?

turbo hardware is tight, no exhaust leaks that I know of, intercooler clamps are tight, motor is just as strong when in boost and makes no fuxored noises, AFR is normal...is the cat clogged?
Old May 24, 2009 | 11:42 PM
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Maybe your tach is off?
Old May 24, 2009 | 11:55 PM
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Why do you have a cat? You don't strike me as the tree hugging type! I would think a cat, clogged or not would be enough to kill some pretty decent spool.
Old May 24, 2009 | 11:58 PM
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Yea.....are you really still running a cat?
Old May 25, 2009 | 12:16 AM
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What kind of timing are you running? You could always pull less timing to spool the turbo faster.
Old May 25, 2009 | 12:46 AM
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How did you verify that there were no exhaust leaks?
Old May 25, 2009 | 01:03 AM
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It is jeolus of my 5psi greddy kit. LOL

Did you get a testpipe from enthuza? Try it in place and see if it fixes it.
Old May 25, 2009 | 01:17 AM
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Originally Posted by Link
What kind of timing are you running? You could always pull less timing to spool the turbo faster.
He posted this spark map in my dyno thread to help me out a while ago:



From what I've gathered it's dialed in pretty well, I don't think that's the issue.
Old May 25, 2009 | 01:37 AM
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Originally Posted by Link
What kind of timing are you running? You could always pull less timing to spool the turbo faster.
first, that didn't work on the dyno...more advance = earlier spool.

second, why did it change?

Originally Posted by jayc72
How did you verify that there were no exhaust leaks?
feather-duster at the joints, lol.
Old May 25, 2009 | 01:41 AM
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is your boost line expanading :P did your car loose a bunch of weight?
Old May 25, 2009 | 01:59 AM
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I'd bet you've got a leak between manifold and turbo. You stated in another thread that the hardware was loose on a number of occasions during a track day. This seems like the most likely place to start looking.
Old May 25, 2009 | 02:02 AM
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Originally Posted by jayc72
I'd bet you've got a leak between manifold and turbo. You stated in another thread that the hardware was loose on a number of occasions during a track day. This seems like the most likely place to start looking.
i just remembered that and posted it. Going to check it out tomorrow.
Old May 25, 2009 | 03:58 AM
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Originally Posted by hustler
turbo hardware is tight, no exhaust leaks that I know of, intercooler clamps are tight, motor is just as strong when in boost and makes no fuxored noises, AFR is normal...is the cat clogged?
How is it late? As in later than you would like or later than before? If it is later than before, mani to turbo leak is most likely. Or loose WG actuator. Or something else. In that order.
Old May 25, 2009 | 10:18 AM
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what was that stove/vent sealant you chinamen were using for a while? I might try that.
Old May 26, 2009 | 03:25 AM
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Was this a relatively sudden change (like a week or two, or even just one day) or just compared to a few months ago? Higher ambient temps than before? Clogged air filter?
Old May 26, 2009 | 09:18 AM
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Originally Posted by matttheniceguy
Was this a relatively sudden change (like a week or two, or even just one day) or just compared to a few months ago? Higher ambient temps than before? Clogged air filter?
it did this after the first track day.
Old May 26, 2009 | 02:26 PM
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damn, the turbo and the downpipe have a good seal on the feather-duster test...clogged cat? I guess I need to pressure test the intercooler pipes too but they seem like they're all tight with a good seal.
Old May 27, 2009 | 12:37 AM
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WTF is a feather-duster test? Did you try a length of vacuum hose in the ear test?
Old May 27, 2009 | 07:49 AM
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Originally Posted by jayc72
WTF is a feather-duster test? Did you try a length of vacuum hose in the ear test?
Small air leaks will displace the feathers on the duster, showing you where air (exhaust) is escaping the system.
Old May 27, 2009 | 09:01 AM
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Originally Posted by BradC
Small air leaks will displace the feathers on the duster, showing you where air (exhaust) is escaping the system.
Reminds me when i suggested to someone on m.net they use a tissue to do the same test. They refused claiming it would catch on fire and the car would explode.



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