Why Was My Gtr On Unlimited Boost?

[druzilla32]

just wondering what could cause a GTR to start running unlimited boost.

(The boost restrictor has been removed)

i have been told that removing the pipes that go to the wastegate actuators and blocking off the hoses will cause the turbos to only run about 8PSI assuming the actuators are fine.

basically i want to limit boost to around 12 psi

[1400r]

should be right as the actuator wont have any pressure from the line to help hold it closed is it would only be relying on the spring pressure to hold the wastegate closed.

( I could be wrong though I'm not very smart)

either that or swap hoses with some care 26 owner this is probably the easier option so you dont run the risk of blowing your motor

[paulr33]

you should get a boost controller?

why mess with dodgy hack ups on 15 year old+ turbo's with cermaic wheels. just asking for it to go bang. if you unplug the pressure lines to the stock actuators then the spring will never move, thus the gate will never open so it will keep winding up pressure for ever

[pnblight]

if you disconnect the actuators line you will get max boost the actuators a able to hold on the std turbo that around 19 psi (way to much for the std turbo)

if you put a direct line from boost to actuators you will get the minium the boost the actuators will run ~7 or 8 psi (i think not sure on this spring set)

a bleed valve or boost controller just bleeds off a some of the boost pressure being supplied to the actuators to govern the pressure between these to points

pete

ps buy a $99 dollar turbo smart bleed valve and you will be able to set your boost fine, just keep the lines as short as posible to reduce piking.

[viking]

i hav a avcr on mine with standard turbos. last dyno tune they could only hold just 1bar consistently. does this sound right?

[lang]

the gate will never open so it will keep winding up pressure for ever

<{POST_SNAPBACK}>

feels fast tho

[druzilla32]

well the motor is getting put in the car today after a rebuild with some tastey parts..

before 2 pistons fried it was (for some reason) running unlimited boost... it went to around 12psi at only 2500rpm!

i want to limit the boost as much as possible.. and i dont know why it was running unlimited.

this will be for the run in process then i will be getting a power FC.

i want it limited to around 7PSI

[pnblight]

well the motor is getting put in the car today after a rebuild with some tastey parts..

before 2 pistons fried it was (for some reason) running unlimited boost... it went to around 12psi at only 2500rpm!

i want to limit the boost as much as possible.. and i dont know why it was running unlimited.

this will be for the run in process then i will be getting a power FC.

i want it limited to around 7PSI

<{POST_SNAPBACK}>

like i said run a boost line direct to the actuators with give you minium boost (to what the turbos are preset to)

[druzilla32]

ok,

so does anybody know why it could have started to run unlimited..

cuz rather then try to cover the problem with a boost controller i would rather find out what the problem was, and fix it

[blind_elk]

It appears you have disconnected the boost pressure line from the wastegate itself - is this correct? If so, where does the wastegate get a signal of what boost has been generated?

The boost signal forces the wastegate open when a preset boost level - enough to overcome the spring - is genarated. The spring actually holds the wastegate SHUT. So without a boost signal, the wastgate stays shut, and boost keeps on building.

Whoever told you you could remove the wastegate lines should be sent the bill for the repairs to your engine.

[druzilla32]

Whoever told you you could remove the wastegate lines should be sent the bill for the repairs to your engine.

<{POST_SNAPBACK}>

nah,

what happened was, i heard a noise that sounded like an exhaust gasket was gone (statrted to sound like a truck)

so i took off a few pipes to see if i could see any part of the gasket around the turbo had blown off. i may have taken i hose off the wastegate, but it was put back on and everything was normal again before i started the car.

after this.. for some reason it was on unlimited boost

i checked all the hoses around the wastegate.. i saw one was corroded.. i changed it with a new one.. still made no difference...

i have now been told that disconnecting the wastegate hoses will cause it to run off the spring and boost will limit to around 8psi.. however i agree with you, i think it would cause it to run unlimited.

could a wastegate be stuck... stuffed actuator?

[Beer Baron]

Q: Why Was My Gtr On Unlimited Boost?

A: you messed around with a car you don't know much about and as a result popped your motor.

I can't beleive you are "helping the builder out a lot with the build" when you can't understand the simple basics of boost control mate. it's not that complex.

it's not a stuffed actuator mate. you f**ked up the pressure feed to the wastegate actuators. simple.

sorry if i sound rude but it bugs me that people keep blowing up cars through ignorance.

[The Mafia]

i have been told that removing the pipes that go to the wastegate actuators and blocking off the hoses will cause the turbos to only run about 8PSI assuming the actuators are fine.

<{POST_SNAPBACK}>

Holy shit.

Who ever told you this, should NEVER EVER EVER EVER be allowed to drive a turbo'd car. EVER.

[druzilla32]

Q: Why Was My Gtr On Unlimited Boost?

A: you messed around with a car you don't know much about and as a result popped your motor.

I can't beleive you are "helping the builder out a lot with the build" when you can't understand the simple basics of boost control mate. it's not that complex.

it's not a stuffed actuator mate. you f**ked up the pressure feed to the wastegate actuators. simple.

sorry if i sound rude but it bugs me that people keep blowing up cars through ignorance.

<{POST_SNAPBACK}>

arhhhh..

the lines were fine.. they were not leaking, they were connected.. and it was still running unlimited boost.

so your saying.. if this hose was taken off... then put back on 5 mins later exactly the same way, it will f**k it up?

[predator]

x x

Edited September 22, 2005 by predator

[Beer Baron]

arhhhh..

the lines were fine.. they were not leaking, they were connected.. and it was still running unlimited boost.

so your saying.. if this hose was taken off... then put back on 5 mins later exactly the same way, it will f**k it up?

<{POST_SNAPBACK}>

this might be my great detectives brain at work but lets look at the situation again shall we:

car is running normal boost

you disturb the pressure feed hoses

you put them back

car is now running unlimited boost

nothing else major has been done except you disturbing the pressure feed hoses

my conclusion is quite simple, you didn't put them back correctly. If you beleive anything else you are dreaming.

[druzilla32]

i know how to take off a hose and put it back on. Im 100% sure it was put back on correctly as it was tripple checked.

the guys with my car said a lot of the hoses on the zaust side were corroded. but i was making sure that that was actually the problem before i put the original actuators back in.

i am not saying that while i was doing something the pipes corroded all of a sudden, obviosly i must have moved something and one of the corroded pipes split.

you seem prety certain the actuators are fine, so i will see how it goes with the new hoses.

[druzilla32]

ps.

no need to be smart

thanks for your help too

[druzilla32]

well actually,

this will bring the boost back to around 1bar as the restrictor had been removed before i got it..

i think a zip tie around the hose to the boost solinoid would restrict it

Edited September 22, 2005 by druzilla32

[TTT]

GTR, zip tie's to restrict boost.

*shakes head*