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?

Maybe your tach is off?

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.

Yea.....are you really still running a cat?

What kind of timing are you running? You could always pull less timing to spool the turbo faster.

How did you verify that there were no exhaust leaks?

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.

He posted this spark map in my dyno thread to help me out a while ago:

http://i43.tinypic.com/14vtvrk.jpg

From what I've gathered it's dialed in pretty well, I don't think that's the issue.

first, that didn't work on the dyno...more advance = earlier spool.

second, why did it change?

feather-duster at the joints, lol.

is your boost line expanading :P did your car loose a bunch of weight?

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.

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.

what was that stove/vent sealant you chinamen were using for a while? I might try that.

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.

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.

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.

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. :loser: