halimsteven

hi guys,
i have a problem with the turbo. frst, i went to KDR to tuned my car...my set up:
greddy turbo, INT-X, injectors...boost controller (AEM), AFR gauges...ok this is the problem....
everytime my car is in boosting, it goes more than 7psi, and it reaches sometimes almost 11 psi ..i got scared....i thought i had a problem with the boost controller..
so i decided to take it out from the solenoid...so it uses the greddy spring pressure itself....i try it again, it went 8psi (3rd gear from 4k - 8k), next, i tried ...in the 4th gear. (from 4k -8k), it went 9.8psi on my gauge.....when i saw it more than 9. i stopped. ussualy the greddy turbo from 9psi, it went down to 5-6 psi...but this is the opposite, from 6 to 8,9,10 psi...keep increasing...i was confused

do you guys know what seem to be the problem? please let me know...i

turborx8

iTrader: (1)

Have you done the GReddy fix#2 yet?

halimsteven

yup, i did all fixes. i am using the boost controller, but it seems that it bypass it. i put my alarm around 8.5 psi, but still it goes to 9.5 psi. it didn't shut down. o well, even if i turns off the boost controller, it boost more than 6psi which is not suppose to as i know.
anybody have any idea? i don't think anybody has this problem...i am trying to figure out....
steven

staticlag

so you took the boost controller solenoid completely off? There might be an air leak in the solenoid diaphram, so its best to take it off completely before declaring that its not the boost controller.

halimsteven

ok, i didn't take it off completely, but you know, the solenoid has connection from the wastegate and turbo pressure. i took them off from solenoid, and connected them together, so they don't use solenoid at all. so it means, the turbo will use its own spring pressure, 6psi something like that, but after the fix #2, it's supposed to be 4-5 psi, but it keeps overboosting more than 6 psi, almost 8 - 9 psi.
staticlag, what type of boost controller do you use?

StealthTL

iTrader: (1)

You sure the actuator actually turns the shaft?

The symptoms sound like the wastegate is stuck shut, or split. Try putting 10psi on the diaphragm, see if it moves freely.


S

mysql

several of us on the stock greddy turbo setup would get random spikes where even though the boost controller was setup to 8 psi, it would go to 11.

my solution to this was to raise the boost controller so it always went to 11, then I wouldn't know if it was intentionally going that high or not

Upgrading to the GT3071R that problem went away... so I'm going to assume the wastegate actuator is crap. You can replace it for around $80 from ATP turbo.

halimsteven

do you think it's wastegate problem? o well, i diidn't use the boost controller now, but still boosting almost 9psi. what will happen if the wastegate doesn't work properly, will it give more air to the engine? will give more psi?
steven

staticlag

That works! I just wasn't sure how you were bypassing it.

I'm currently using just the wastegate spring keeps it from 10 to 9psi depending on how hot the spring gets.

halimsteven

so mysql, you said that it is normal if we set up the boost controller at 8 psi, and you see almost 10 - 11 psi as a random spike? is it going to be ok? don't you think it will be dangerous for the engine? does it happen to you a lot of times? i should have bought your wastegate....so what is the purpose of the boost limiter if we can't limit it...

i can't wait to upgrade it....

halimsteven

have you ever seen your turbo gives more than psi that you expected?

mysql

yeah... I'd say 85% - 95% of the time it would hit the desired 8 psi. But randomly it would seemingly ignore that and go up to 11 psi.

The car was setup properly for 11, so it didn't matter if I went that high or not. So I just increased the boost controller settings till it was setup for 11, then it always boosted to the desired number.

Lame fix, but I never did install the ATP turbo's wastegate actuator to see if it fixed the problem or not. Shortly after I received it in the mail, Jeff announced his turbo upgrade, so I bought that too, and abandoned the greddy turbo.

I've spoken with at least two others who reported similar findings, so it sounds common enough that we all might have had it.

halimsteven

ok, i might just tune it for 11 psi, but how could you tune it for 11 psi if it can't hold the boost for 11 psi? mine, it will boost pike when ever i start from higher gear...when i boost from 4th gear, it went to 8.9 psi, it went 7 psi first, but it went up to 9 psi...i am getting headache from this...btw mysql, do you still have the wastegate?
steven

mysql

if you have a greddy boost controller, it has values for gain, and boost consistency which adjust how quickly and how it holds the boost. These settings will let you adjust the spiking and whatnot, but it doesn't do squat for the occasional 11 psi spike we got.

Grouch

Yup. I have the same problem and it scared me when it happened to me a few times. I thought something popped and didn't know how to describe it in an earlier thread. I blamed it on my boost controller or my lack of knowledge on how to set it up properly but it was wierd because I could never reproduce the same problem.

rkostolni

I had that problem with my setup. I believe its caused by the wastegate just not being capable of flowing enough to properly control the boost. If you're preloading the actuator, you could be contributing to the problem by delaying the opening of the wastegate flap. I had Mazsport port out the wastegate and then loosened the preload on the actuator. That seemed to help alot.

halimsteven

mmm, so i need to do the same modification ? how about the mysql talk about, change the wastegate actuator?

so does it still keep happening to you now? does it get solved? or you let it go like that? i did it again today, what happen was my boost controller recognized the over boost, and it shut it down. it was 10.7 psi. so it means my boost controller is good.

ok, now i don't think anybody is using AEm boost controller. i have AEM boost controller and it acts as a boost gauge. it's simple, i just need to adjust the spring pressure (as low as i can) and boost set up. that's all. i don't have the greddy..

staticlag

Under WOT my boost spikes from 10 to 13 psi at exactly 6500 rpms. This is from the ports opening, takes a second to stabilize, I can reproduce the spike in any ambient condition. The whole thing happens in maybe 1/2 a second but can blow the engine if you haven't tuned rich for it. Just tune for enough fuel up to 15psi and you should be fine.

staticlag

can you post a screen shot of your idle/aux table, your load table, your wot rpm table, and your aux rpm table?

mysql

here's the actuator I was talking about:

ATP-WGT-019 Internal Wastegate Actuator - Special 7 psi 1 $79.00

You'd need to have a bracket made up to support it, as it's not direct bolt on:

http://www.atpturbo.com/Merchant2/me...egory_Code=GRT

One or two people on this forum have done it already and reported success with it. I still think the 3071R is the better choice though

halimsteven

yeah, i will do that soon by next weekend, and i will tell my tuner what happen with the turbo....

i will do that, but as you know that it was tuned when i put my oost controller as 7.25 psi..and he cleaned up little bit when we ran it on the street.


yeah, but i think i should upgrade it to 3071R..but i just enjoy it a few months...i need it to break down, then i will upgrade it..hahhaa

steven

halimsteven

for people who like to know if there is a way to help the boost spike from greddy turbo, i will do this next week, by changing the actuator as mysql suggested. i will do it by next week, and i will post up how it is...
steven