The car feels faster at 15psi than it does at 20psi!!! What's the deal??

What are you tuned with? What is your AFR at 15psi vs 20psi?

Knock sensor going off, timing being pulled, and likely boost leaks is probably what is going on without any other information.

i use apexi safc and wideband. along with logger on my phone to look at other readings
afr at between 11.5 and 10.5

EGLTAWLN said:

Knock sensor going off, timing being pulled, and likely boost leaks is probably what is going on without any other information.

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no boost leak. timing is at 12-14 at wot with 15 and 20psi at about 5000rpm

EGLTAWLN said:

Knock sensor going off, timing being pulled, and likely boost leaks is probably what is going on without any other information.

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ive done a boost leak test 2 weeks ago and flared the end of all my fittings. (it was really hard to get back together with the flares)
i wish i had to way to count knock. i dont hear anything. it runs good and smooth.
as soon as i sell my parts car ill have dsmlink. (I WANT IT BAD)
ive learned so much about tuning from reading these forums the last 3 months. i hate only having a AFC to make changes. i know i can get a 1g CAS and adjust timing now, but id rather wait till i have link.

Gottiboy said:

11.5 and 10.5

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That is a pretty big range, are you saying it fluctuates between the two numbers during the pull?
So you have a 50 trim on 550's and an afc? I would say to run it at a lower boost until you get link. When you skew the airflow readings via an afc it will in turn affect the timing map as well.

Try to get your hand on the back of the knock sensor itself. If it is sticky and gooey, it is bad/going bad. Could explain a loss of power. Otherwise maybe heat soaking going on with an off brand intercooler but if it's big enough, it shouldn't. Also, 50 trim turbo is barely spinning at 20 psi. Such a big turbo needs a lot more boost to see the benefit.

lasershark said:

That is a pretty big range, are you saying it fluctuates between the two numbers during the pull?
So you have a 50 trim on 550's and an afc? I would say to run it at a lower boost until you get link. When you skew the airflow readings via an afc it will in turn affect the timing map as well.

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at lower rpm wot its 11.5 and as i get 6-7k it gets richer 10

should i put the evo3 16g turbo (welded internal wastegate) i have, on it? its brand new. and the manifold i got with it has an external wastegate on it

All I was getting at is, "don't go trying to max that turbo out on 550's and an afc". The 50 trim maxes out around 48 lbs/min and the evo 3 max airflow is around 43 lbs/min and both those turbos are more than capable of maxing out your injectors. Just save some coin man keep your eyes on the classifieds and snag a good deal on dsmlink v3 so you can really start having fun. Shit, sell one of the turbos and you are at least half way there!

im trying to get it so bad i have a 98 gst up for trade for dsmlink and injectors

Gottiboy said:

im trying to get it so bad i have a 98 gst up for trade for dsmlink and injectors

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Well if you sell it, you won't need ecmlink

Straight 10 is pig rich man, by now you have probably fouled out your plugs and is most likely causing your problems. Another option is to have your ECU flashed depending what kind of ECU you have (EPROM or black box only). I'm not entirely sure if MY1GDSM is still in this business or not but he can tune the car for you, there's a couple of other guys in the freelance page that could help you with tuning as well.

lasershark said:

Well if you sell it, you won't need ecmlink

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no i have 3 gs-t's
a 99 parts car
a 98 auto (i got it on a good trade deal)
and my 98 daily driver

oneslowwdsm said:

Straight 10 is pig rich man, by now you have probably fouled out your plugs and is most likely causing your problems. Another option is to have your ECU flashed depending what kind of ECU you have (EPROM or black box only). I'm not entirely sure if MY1GDSM is still in this business or not but he can tune the car for you, there's a couple of other guys in the freelance page that could help you with tuning as well.

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im running a black box right now. but dont wanna waste money on flash equipment when link is my real goal.
is there any tune out there that adjust to a target AFR?
my stock timing changes seem to be right on with what other 2g are running from what ive seen.

oneslowwdsm said:

Straight 10 is pig rich man, by now you have probably fouled out your plugs and is most likely causing your problems. Another option is to have your ECU flashed depending what kind of ECU you have (EPROM or black box only). I'm not entirely sure if MY1GDSM is still in this business or not but he can tune the car for you, there's a couple of other guys in the freelance page that could help you with tuning as well.

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i see guys say they run 10.5 at full boost with no problems.
and do you know if safc changes timing ( been told that it does)
and if so, does adding fuel advance or retard timing?

or is changing the afr what makes the ecu adjust timing?

i know this doesnt belong in this thread but when you find knowledgeable guys better to ask why they are already talking to you.

Gottiboy said:

i see guys say they run 10.5 at full boost with no problems.
and do you know if safc changes timing ( been told that it does)
and if so, does adding fuel advance or retard timing?

or is changing the afr what makes the ecu adjust timing?

i know this doesnt belong in this thread but when you find knowledgeable guys better to ask why they are already talking to you.

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The ecu will change timing based on the airflow that it is measuring (maf sensor). When you add larger injectors you trick the ecu with the safc into thinking/seeing that there is less air coming into the engine. The when the ecu "sees" less air in lowers the injector pulse width which in turn lets you run the larger injectors.

The problem lies when you lower the airflow the ecu sees (via safc); the ecu will in turn allow/enable the timing map to become more aggressive. More aggressive meaning increasing the timing. More timing with more boost opens the possibility and probability of knock.

how come with such a big turbo and only 550cc injectors does my car never run lean?
once i even installed a mbc and didnt pay attention to where it was set and almost hit 30 psi and my afr bottomed out rich??????